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Wang Y, Lee S, Ha Y, Lam W, Chen SR, Dutschman GE, Gullen EA, Grill SP, Cheng Y, Fürstner A, Francis S, Baker DC, Yang X, Lee KH, Cheng YC. Tylophorine Analogs Allosterically Regulates Heat Shock Cognate Protein 70 And Inhibits Hepatitis C Virus Replication. Sci Rep 2017; 7:10037. [PMID: 28855547 PMCID: PMC5577180 DOI: 10.1038/s41598-017-08815-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 07/19/2017] [Indexed: 12/12/2022] Open
Abstract
Tylophorine analogs have been shown to exhibit diverse activities against cancer, inflammation, arthritis, and lupus in vivo. In this study, we demonstrated that two tylophorine analogs, DCB-3503 and rac-cryptopleurine, exhibit potent inhibitory activity against hepatitis C virus (HCV) replication in genotype 1b Con 1 isolate. The inhibition of HCV replication is at least partially mediated through cellular heat shock cognate protein 70 (Hsc70). Hsc70 associates with the HCV replication complex by primarily binding to the poly U/UC motifs in HCV RNA. The interaction of DCB-3503 and rac-cryptopleurine with Hsc70 promotes the ATP hydrolysis activity of Hsc70 in the presence of the 3' poly U/UC motif of HCV RNA. Regulating the ATPase activity of Hsc70 may be one of the mechanisms by which tylophorine analogs inhibit HCV replication. This study demonstrates the novel anti-HCV activity of tylophorine analogs. Our results also highlight the importance of Hsc70 in HCV replication.
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Affiliation(s)
- Ying Wang
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA. .,Institute of Chinese Medical Sciences and State Key Laboratory of Quality Research in Chinese Medicine, University of Macau, Macau, SAR, China.
| | - Sangwon Lee
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Ya Ha
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Wing Lam
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Shao-Ru Chen
- Institute of Chinese Medical Sciences and State Key Laboratory of Quality Research in Chinese Medicine, University of Macau, Macau, SAR, China
| | - Ginger E Dutschman
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Elizabeth A Gullen
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Susan P Grill
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Yao Cheng
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Samson Francis
- Department of Chemistry, The University of Tennessee, Knoxville, TN, 37996, USA
| | - David C Baker
- Department of Chemistry, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Xiaoming Yang
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC, 27599, USA.,Chinese Medicine Research and Development Center, China Medical University and Hospital, Taichung, Taiwan
| | - Yung-Chi Cheng
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT, 06520, USA.
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Piao D, Basavapathruni A, Iyidogan P, Dai G, Hinz W, Ray AS, Murakami E, Feng JY, You F, Dutschman GE, Austin DJ, Parker KA, Anderson KS. Bifunctional inhibition of HIV-1 reverse transcriptase: a first step in designing a bifunctional triphosphate. Bioorg Med Chem Lett 2012; 23:1511-8. [PMID: 23380374 DOI: 10.1016/j.bmcl.2012.12.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Revised: 12/04/2012] [Accepted: 12/10/2012] [Indexed: 11/28/2022]
Abstract
The onset of resistance to approved anti-AIDS drugs by HIV necessitates the search for novel inhibitors of HIV-1 reverse transcriptase (RT). Developing single molecular agents concurrently occupying the nucleoside and nonnucleoside binding sites in RT is an intriguing idea but the proof of concept has so far been elusive. As a first step, we describe molecular modeling to guide focused chemical syntheses of conjugates having nucleoside (d4T) and nonnucleoside (TIBO) moieties tethered by a flexible polyethylene glycol (PEG) linker. A triphosphate of d4T-6PEG-TIBO conjugate was successfully synthesized that is recognized as a substrate by HIV-1 RT and incorporated into a double-stranded DNA.
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Affiliation(s)
- Dongyuan Piao
- Brown University, Department of Chemistry, Providence, RI 02912, United States
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3
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Tsou LK, Chen CH, Dutschman GE, Cheng YC, Hamilton AD. Blocking HIV-1 entry by a gp120 surface binding inhibitor. Bioorg Med Chem Lett 2012; 22:3358-61. [PMID: 22487177 DOI: 10.1016/j.bmcl.2012.02.079] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Revised: 02/18/2012] [Accepted: 02/23/2012] [Indexed: 11/27/2022]
Abstract
We report the mode of action of a proteomimetic compound that binds to the exterior surface of gp120 and blocks HIV-1 entry into cells. Using a one cycle time-of-addition study and antibody competition binding studies, we have determined that the compound blocks HIV-1 entry through modulation of key protein-protein interactions mediated by gp120. The compound exhibits anti-HIV-1 replication activities against several pseudotype viruses derived from primary isolates and the resistant strains isolated from existing drug candidates with equal potency. Together, these data provide evidence that the proteomimetic compound represents a novel class of HIV-1 viral entry inhibitor that functions through protein surface recognition in analogy to an antibody.
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Affiliation(s)
- Lun K Tsou
- Department of Chemistry, Yale University, New Haven, CT 06520, United States
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4
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Haraguchi K, Shimada H, Kimura K, Akutsu G, Tanaka H, Abe H, Hamasaki T, Baba M, Gullen EA, Dutschman GE, Cheng YC, Balzarini J. Synthesis of 4'-Ethynyl-2'-deoxy-4'-thioribonucleosides and Discovery of a Highly Potent and Less Toxic NRTI. ACS Med Chem Lett 2011; 2:692-697. [PMID: 23795238 DOI: 10.1021/ml2001054] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The synthesis of 4'-ethynyl-2'-deoxy-4'-thioribonucleosides was carried out utilizing an electrophilic glycosidation in which 4-ethynyl-4-thiofuranoid glycal 16 served as a glycosyl donor. Electrophilic glycosidation between 16 and the silylated nucleobases (N4-acetylcytosine, N6-benzoyladenine and N2-acetyl-O6-diphenylcarbamoylguanine) was carried out in the presence of N-iodosuccinimide (NIS) leading to the exclusive formation of the desired β-anomers 29, 33 and 36. Anti-HIV studies demonstrated that these 4'-thio nucleosides were less cytotoxic to T-lymphocyte (i.e. MT-4 cells) than the corresponding 4'-ethynyl derivatives of 2'-deoxycytidine (44), 2'-deoxyadenosine (45) and 2'-deoxyguanosine (46). Comparison of the selectivity indices (SI) was made between 4'-thionucleosides (32, 41 and 43) and the corresponding 4'-oxygen analogues 44-46 by using the reported CC50 and EC50 values. In the case of cytosine and adenine nucleosides, comparable SI values were obtained: 32 (545) and 45 (458); 41 (>230) and 45 (1,630). In contrast, 4'-ethynyl-2'-deoxy-4'-thioguanosine 43 was found to possess a SI value of >18,200, which is twenty times better than that of 46 (933).
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Affiliation(s)
- Kazuhiro Haraguchi
- School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Hisashi Shimada
- School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Keigo Kimura
- School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Genta Akutsu
- School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Hiromichi Tanaka
- School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Hiroshi Abe
- RIKEN Advanced Science Institute, Nanomedical Engineering Laboratory, 2-1, Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Takayuki Hamasaki
- Division of Antiviral Chemotherapy, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 89-8544, Japan
| | - Masanori Baba
- Division of Antiviral Chemotherapy, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 89-8544, Japan
| | - Elizabeth A. Gullen
- Department of Pharmacology, School of Medicine, Yale University, New Haven, Connecticut 06520, United States
| | - Ginger E. Dutschman
- Department of Pharmacology, School of Medicine, Yale University, New Haven, Connecticut 06520, United States
| | - Yung-Chi Cheng
- Department of Pharmacology, School of Medicine, Yale University, New Haven, Connecticut 06520, United States
| | - Jan Balzarini
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, B-3000 Leuven, Belgium
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5
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Zhang W, Dutschman GE, Li X, Cheng YC. Quantitation of paclitaxel and its two major metabolites using a liquid chromatography–electrospray ionization tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2011; 879:2018-22. [DOI: 10.1016/j.jchromb.2011.05.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 04/15/2011] [Accepted: 05/13/2011] [Indexed: 11/26/2022]
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6
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Zhang W, Tan S, Paintsil E, Dutschman GE, Gullen EA, Chu E, Cheng YC. Analysis of deoxyribonucleotide pools in human cancer cell lines using a liquid chromatography coupled with tandem mass spectrometry technique. Biochem Pharmacol 2011; 82:411-7. [PMID: 21620803 DOI: 10.1016/j.bcp.2011.05.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/10/2011] [Accepted: 05/11/2011] [Indexed: 10/18/2022]
Abstract
Endogenous ribonucleotides and deoxyribonucleotides play a critical role in cell function, and determination of their levels is of fundamental importance in understanding key cellular processes involved in energy metabolism and molecular and biochemical signaling pathways. In this study, we determined the respective ribonucleotide and deoxyribonucleotide pool sizes in different human cell lines using a simple sample preparation method and LC/MS/MS. This assay was used to determine alterations in deoxyribonucleotide pools in human pancreatic PANC1 cells in response to hypoxia and to treatment with either hydroxyurea or aphidicolin. The levels of all deoxyribonucleotide metabolites decreased with hypoxia treatment, except for dUMP, which increased by two-fold. This LC/MS/MS assay is simple, fast, and sensitive, and it represents a significant advance over previously published methodologies.
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Affiliation(s)
- Wei Zhang
- Department of Pharmacology, Section of Medical Oncology, Yale School of Medicine, New Haven, CT 06520, USA.
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7
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Zhang W, Saif MW, Dutschman GE, Li X, Lam W, Bussom S, Jiang Z, Ye M, Chu E, Cheng YC. Identification of chemicals and their metabolites from PHY906, a Chinese medicine formulation, in the plasma of a patient treated with irinotecan and PHY906 using liquid chromatography/tandem mass spectrometry (LC/MS/MS). J Chromatogr A 2010; 1217:5785-93. [PMID: 20696432 PMCID: PMC3668335 DOI: 10.1016/j.chroma.2010.07.045] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 07/02/2010] [Accepted: 07/13/2010] [Indexed: 11/20/2022]
Abstract
Traditional Chinese Medicine (TCM) is increasingly being used in combination with Western medicine. In general, TCM is comprised of multiple components in sharp contrast to Western medicine, where a single active chemical is used. Presently, there are no well-established standards for most of the chemical compounds of TCM and their respective metabolites. Moreover, there are no formal analytical methods for the identification of these chemicals, especially in trace amounts. The ability to measure the pharmacokinetic behaviors of chemicals and their metabolites from these herbal formulations are critical in understanding of the action of TCM. This paper describes the use of LC/MS/MS along with enzyme treatments and n-octanol/water partition coefficient, to investigate the chemical components of PHY906 and their metabolites in the plasma of a patient with metastatic colorectal cancer (mCRC) treated with irinotecan and PHY906. The chemicals from an aqueous extract of PHY906 and the plasma from a patient was prepared and separated on an Agilent ZORBAX-SB C(18) column, and eluted with acetonitrile/0.05% (v/v) formic acid. From the PHY906 aqueous extract, a total of 57 compounds and 27 metabolites were identified and tentatively assigned structures based on their identified mass spectrometry, enzyme digestion and n-octanol/water partition coefficient. In contrast, analysis of patient plasma identified only 33 chemicals and new metabolites. These findings demonstrated that LC/MS/MS was and effective and reliable method for studying the parent chemicals of the Chinese herbal medicine PHY906 and their metabolites in a patient with metastatic colorectal cancer.
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Affiliation(s)
- Wei Zhang
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Muhammad W. Saif
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Section of Medical Oncology, Department of Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520
| | - Ginger E. Dutschman
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Xin Li
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Wing Lam
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Scott Bussom
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Zaoli Jiang
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| | - Min Ye
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- The State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, P.R. China
| | - Edward Chu
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Section of Medical Oncology, Department of Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520
| | - Yung-Chi Cheng
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
- Developmental Therapeutics Program, Yale Cancer Center, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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8
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Hines J, Ju R, Dutschman GE, Cheng YC, Crews CM. Reversal of TNP-470-induced endothelial cell growth arrest by guanine and guanine nucleosides. J Pharmacol Exp Ther 2010; 334:729-38. [PMID: 20571059 DOI: 10.1124/jpet.110.169110] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mechanism of action of TNP-470 [O-(chloroacetyl-carbamoyl) fumagillol], which potently and selectively inhibits the proliferation of endothelial cells, is incompletely understood. Previous studies have established its binding protein and the most distal effector of its growth arrest activity as methionine aminopeptidase 2 (MetAP-2) and p21(WAF1/CIP1), respectively. However, the mechanistic steps between these two effectors have not been identified. We have found that addition of exogenous guanine and guanine-containing nucleosides to culture medium will completely reverse the cytostatic effect of TNP-470 on both cultured bovine aortic and mouse pulmonary endothelial cells. Western blotting showed that supplementation with exogenous guanosine reverses the induction of p21(WAF1/CIP1) by TNP-470. This "rescue" by guanine/guanosine was abolished when the guanine salvage pathway of nucleotide biosynthesis was inhibited with Immucillin H, suggesting that TNP-470 might reduce de novo guanine synthesis in endothelial cells. However, an analysis of inosine 5'-monophosphate dehydrogenase, the rate-limiting enzyme in de novo guanine synthesis and target of the antiangiogenic drug mycophenolic acid, showed no TNP-470-induced changes. Curiously, quantitation of cellular nucleotides confirmed that GTP levels were not reduced after TNP-470 treatment. Addition of guanosine at the start of G(1) phase causes a doubling in GTP levels that persists to the G(1)/S phase transition, where commitment to TNP-470 growth arrest occurs. Thus, guanine rescue involves an augmentation of cellular GTP beyond physiological levels rather than a restoration of a drug-induced GTP deficit. Determining the mechanism whereby this causes restoration of endothelial cell proliferation is an ongoing investigation.
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Affiliation(s)
- John Hines
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA
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9
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Tsou LK, Dutschman GE, Gullen EA, Telpoukhovskaia M, Cheng YC, Hamilton AD. Discovery of a synthetic dual inhibitor of HIV and HCV infection based on a tetrabutoxy-calix[4]arene scaffold. Bioorg Med Chem Lett 2010; 20:2137-9. [PMID: 20202840 DOI: 10.1016/j.bmcl.2010.02.043] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Accepted: 02/10/2010] [Indexed: 10/19/2022]
Abstract
A potential anti-HIV and HCV drug candidate is highly desirable as coinfection has become a worldwide public health challenge. A potent compound based on a tetrabutoxy-calix[4]arene scaffold that possesses dual inhibition for both HIV and HCV is described. Structural activity relationship studies demonstrate the effects of lower-rim alkylation in maintaining cone conformation and upper-rim interacting head groups on the calix[4]arene play key roles for its potent dual antiviral activities.
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Affiliation(s)
- Lun K Tsou
- Department of Chemistry, Yale University, New Haven, CT 06520, United States.
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10
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Paintsil E, Grill SP, Dutschman GE, Cheng YC. Comparative study of the persistence of anti-HIV activity of deoxynucleoside HIV reverse transcriptase inhibitors after removal from culture. AIDS Res Ther 2009; 6:5. [PMID: 19386130 PMCID: PMC2684870 DOI: 10.1186/1742-6405-6-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Accepted: 04/22/2009] [Indexed: 04/05/2023] Open
Abstract
Background Most in vitro assays of drug potency may not adequately predict the performance in vivo. Methods to assess the persistence of antiviral activity of deoxynucleoside analogs, which require intracellular activation to the active metabolites that can persist in cells, will be important for designing dosages, combination regimens, and assessing treatment compliance. Using an HIV-IIIB/TZM-bl indicator cell culture system, we assessed the ability of an inhibitor to protect cells from infection and to delay viral rebound after removal of inhibitor from culture. Results The order of protection of cells from HIV-infection was 4'-Ed4T > LFD4C > DDI > D4T > 3TC > AZT > FTC > NVP. The fold-increase in EC50 to delay viral rebound was DDI < 4'-Ed4T < LFD4C < FTC < D4T < 3TC < NVP < AZT. The ranking of persistence of anti-HIV activity of the inhibitors based on the two-component assay was DDI > 4'-Ed4T > LFD4C > FTC = D4T > 3TC > NVP > AZT. Conclusion The persistence ranking was derived from assays based on measures of single viral replication-cycle and cumulative inhibition at multiple time-points. Therefore, a better indicator of the pharmacodynamic property of an inhibitor. The persistence of anti-HIV activity assay may complement in vitro potency assays to better predict in vivo performance of nucleoside analogs.
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Haraguchi K, Shimada H, Akutsu G, Kimura K, Tanaka H, Hamasaki T, Baba M, Gullen EA, Dutschman GE, Cheng YC, Balzarini J. Synthesis and anti-HIV activity of 4'-C-ethynyl-2'-deoxy-4'-thio-nucleosides. Nucleic Acids Symp Ser (Oxf) 2009; 53:97-98. [PMID: 19749278 DOI: 10.1093/nass/nrp049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Synthesis of 4'-C-ethynyl-2'-deoxy-4'-thionucleosides was carried out based on electrophilic glycosidation using 4-C-ethynyl-4-thiofuranoid glycal. The glycal 15 was prepared as follows: oxidative cleavage of 6 with Pb(OAc)(4) forming the aldehyde 7, aldol reaction of 7 and subsequent silylation to furnish 8, conversion of the formyl group of 8 into an ethynyl group, and finally beta-elimination of the resulting 14 with t-BuLi. The glycosyl donor 16 was prepared by silyl-protection of 15. Electrophilic glycosidation was performed between silylated N(4)-acetylcytosine and 16 in the presence of N-iodosuccinimide. Radical-mediated removal of the introduced iodine atom followed by deprotection gave 4'-C-ethynyl-2'-deoxy-4'-thiocytidine (18).
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Affiliation(s)
- Kazuhiro Haraguchi
- School of Pharmaceutical Sciences, Showa University, Tokyo 142-8555, Japan
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12
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Haraguchi K, Shimada H, Tanaka H, Hamasaki T, Baba M, Gullen EA, Dutschman GE, Cheng YC. Synthesis and Anti-HIV Activity of 4′-Substituted 4′-Thiothymidines: A New Entry Based on Nucleophilic Substitution of the 4′-Acetoxy Group. J Med Chem 2008. [DOI: 10.1021/jm8006036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Haraguchi K, Shimada H, Tanaka H, Hamasaki T, Baba M, Gullen EA, Dutschman GE, Cheng YC. Synthesis and Anti-HIV Activity of 4′-Substituted 4′-Thiothymidines: A New Entry Based on Nucleophilic Substitution of the 4′-Acetoxy Group. J Med Chem 2008; 51:1885-93. [DOI: 10.1021/jm070824s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Paintsil E, Dutschman GE, Hu R, Grill SP, Lam W, Baba M, Tanaka H, Cheng YC. Intracellular metabolism and persistence of the anti-human immunodeficiency virus activity of 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine, a novel thymidine analog. Antimicrob Agents Chemother 2007; 51:3870-9. [PMID: 17724147 PMCID: PMC2151449 DOI: 10.1128/aac.00692-07] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The therapeutic benefits of current antiretroviral therapy are limited by the evolution of drug-resistant virus and long-term toxicity. Novel antiretroviral compounds with activity against drug-resistant viruses are needed. 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine (4'-Ed4T), a novel thymidine analog, has potent anti-human immunodeficiency virus (HIV) activity, maintains considerable activity against multidrug-resistant HIV strains, and is less inhibitory to mitochondrial DNA synthesis in cell culture than its progenitor stavudine (D4T). We investigated the intracellular metabolism and anti-HIV activity of 4'-Ed4T. The profile of 4'-Ed4T metabolites was qualitatively similar to that for zidovudine (AZT), with the monophosphate metabolite as the major metabolite, in contrast to that for D4T, with relatively poor formation of total metabolites. The first phosphorylation step for 4'-Ed4T in cells was more efficient than that for D4T but less than that for AZT. The amount of 4'-Ed4T triphosphate (4'-Ed4TTP) was higher than that of AZTTP at 24 h in culture. There was a dose-dependent accumulation of 4'-Ed4T diphosphate and 4'-Ed4TTP on up-regulation of thymidylate kinase and 3-phosphoglycerate kinase expression in Tet-On RKO cells, respectively. The anti-HIV activity of 4'-Ed4T in cells persisted even after 48 h of drug removal from culture in comparison with AZT, D4T, and nevirapine (NVP). The order of increasing persistence of anti-HIV activity of these compounds after drug removal was 4'-Ed4T > D4T > AZT > NVP. In conclusion, with the persistence of 4'-Ed4TTP and persistent anti-HIV activity in cells, we anticipate less frequent dosing and fewer patient compliance issues than for D4T. 4'-Ed4T is a promising antiviral candidate for HIV type 1 chemotherapy.
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Affiliation(s)
- Elijah Paintsil
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, SHM B226, New Haven, CT 06520, USA
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15
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Hsu CH, Hu R, Dutschman GE, Yang G, Krishnan P, Tanaka H, Baba M, Cheng YC. Comparison of the phosphorylation of 4'-ethynyl 2',3'-dihydro-3'-deoxythymidine with that of other anti-human immunodeficiency virus thymidine analogs. Antimicrob Agents Chemother 2007; 51:1687-93. [PMID: 17353236 PMCID: PMC1855562 DOI: 10.1128/aac.01432-06] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thymidine analogs, including 3'-azido-3'-deoxythymidine (AZT) and 2',3'-dideoxy-3'-deoxythymidine (D4T), are important antiretroviral agents. To exert antiretroviral activity, these analogs undergo a stepwise phosphorylation intracellularly to the active triphosphate metabolites. We previously reported that 4'-substituted D4T with an ethynyl group (i.e., 4'-ethynyl D4T) increased the anti-human immunodeficiency virus (HIV) activity and was active against multidrug-resistant HIV strains. 4'-Ethynyl D4T is a better substrate for phosphorylation by human thymidine kinase 1 than D4T is. In this report, we first studied the enzymes involved in the phosphorylation of 4'-ethynyl D4T from monophosphate to triphosphate metabolites. The 4'-ethynyl D4TMP is phosphorylated by recombinant human TMP kinase with a K(m) of 19 +/- 4 microM and a k(cat) of 0.007 +/- 0.001 s(-1); the relative efficiency is about 9 and 15% of those of D4TMP and AZTMP, respectively. Several enzymes from crude cellular extracts, including nucleoside diphosphate kinase, pyruvate kinase, creatine kinase, and 3-phosphoglycerate kinase, could phosphorylate 4'-ethynyl D4T-diphosphate. The relative phosphorylation efficiencies of 4'-ethynyl D4TDP were about 3 to 25% of those of D4TDP and were generally similar to those of AZTDP. In T-lymphoid cell lines, there was a preponderant accumulation of 4'-ethynyl D4TMP, suggesting that TMP kinase could be the rate-limiting enzyme in the metabolism of 4'-ethynyl D4T. Although the same enzymes are involved in the stepwise phosphorylation of thymidine analogs, their behaviors in phosphorylating metabolites of 4'-ethynyl D4T are different from those of D4T and AZT. Qualitatively, the metabolism of 4'-ethynyl D4T is more similar to that of AZT than to that of its progenitor, D4T.
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Affiliation(s)
- Chih-Hung Hsu
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
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16
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Yang G, Dutschman GE, Wang CJ, Tanaka H, Baba M, Anderson KS, Cheng YC. Highly selective action of triphosphate metabolite of 4'-ethynyl D4T: a novel anti-HIV compound against HIV-1 RT. Antiviral Res 2006; 73:185-91. [PMID: 17109975 DOI: 10.1016/j.antiviral.2006.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 10/04/2006] [Accepted: 10/05/2006] [Indexed: 11/17/2022]
Abstract
2',3'-Didehydro-3'-deoxy-4'-ethynylthymidine (4'-Ed4T), is a recently discovered nucleoside reverse transcriptase inhibitor (NRTI) showing a 5- to 10-fold greater anti-human immunodeficiency virus type 1 (HIV-1) activity and less cellular and mitochondrial toxicity than its parental compound, stavudine (D4T). It is also active against a variety of NRTI-resistant HIV-1 mutants under non-cytotoxic concentrations. In this study, the effects of 4'-Ed4TTP, which is the triphosphate metabolite of 4'-Ed4T, on HIV-1 reverse transcriptase (RT) activity were investigated. We found that 4'-Ed4TTP was a substrate of HIV-1 RT serving as a DNA chain terminator, and it inhibited the DNA polymerase activity of RT more efficiently than D4TTP. The value of Ki(4'-Ed4TTP)/Km(dTTP) is 0.15 for DNA/RNA primer/template duplex (P/T), but 0.7 for DNA/DNA P/T, suggesting 4'-Ed4TTP inhibits RT more efficiently during RNA-dependent DNA synthesis than DNA-dependent DNA synthesis. 4'-Ed4TTP was also found to inhibit the 3TC (Lamivudine)-resistant RT mutant, M184V, with 3-fold less efficiency than the wild type (wt) RT. 4'-Ed4TTP showed much less inhibitory effects toward major host DNA polymerases. Overall, our results suggest that 4'-Ed4TTP is the active form for anti-HIV-1 activity via its inhibitory effect against RT.
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Affiliation(s)
- Guangwei Yang
- Department of Pharmacology, School of Medicine, Yale University, 333 Cedar Street, New Haven, CT 06520, USA
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17
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Kumamoto H, Onuma S, Tanaka H, Dutschman GE, Cheng YC. 3'-Carbon-substituted pyrimidine nucleosides having a 2',3'-dideoxy and 2',3'-didehydro-2',3'-dideoxy structure: synthesis and antiviral evaluation. Antivir Chem Chemother 2006; 17:225-34. [PMID: 17066900 DOI: 10.1177/095632020601700406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The bis(tributylstannyl) derivative of 2',3'-didehydro-2',3'-dideoxyuridine (d4U) underwent an anionic 5'-O-->3'-C stannyl migration to yield the 3'-tributylstannyl-d4U. This compound, with its vinylstannane structure, allowed ready access to the preparation of 3'-carbon-substituted analogues through the Stille reaction. A conventional transformation of the uracil moiety of these d4U analogues led to the corresponding 2',3'-didehydro-2',3'-dideoxycytidine (d4C) counterparts. Some 2',3'-dideoxycytidine (ddC) analogues were also synthesized. Antiviral evaluation revealed that none of these analogues showed activity against HIV, hepatitis B virus, herpes simplex virus-1 (HSV-1) and HSV-2.
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Affiliation(s)
- Hiroki Kumamoto
- School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, Japan.
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18
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Haraguchi K, Takeda S, Sumino M, Tanaka H, Dutschman GE, Cheng YC, Nitanda T, Baba M. A new approach to the synthesis of 4'-carbon-substituted nucleosides: development of a highly active anti-HIV agent 2', 3'-didehydro-3'-deoxy-4'-ethynylthymidine. Nucleosides Nucleotides Nucleic Acids 2005; 24:343-7. [PMID: 16247949 DOI: 10.1081/ncn-200059774] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Oxidation of 3'-O-TBDMS-4',5-unsaturated thymidine 3 with dimethyldioxirane (DMDO) allowed the isolation of the epoxide 4. Upon reacting with organosilicon reagents in the presence of SnCl4, 4 underwent stereoselective ring opening to give 4'-alpha-allyl (6), 4'-alpha-(2-bromoallyl) (7), 4'-alpha-(cyclopenten-3-yl) (8), and 4'-alpha-cyano (9) derivatives of thymidine. Reactions of the 3'-epimer 12 with organoaluminum reagents gave 4'-alpha-methyl (13), 4'-alpha-vinyl (14), and 4'-alpha-ethynyl (15) analogues. Compounds 13-15 were transformed into corresponding 2',3'-didehydro-3'-deoxy derivatives. Evaluation of their ability to inhibit the replication of HIV in cell culture showed that 4'-ethynyl-d4T (19) is more potent and less toxic than the parent compound d4T.
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19
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Ray AS, Hernandez-Santiago BI, Mathew JS, Murakami E, Bozeman C, Xie MY, Dutschman GE, Gullen E, Yang Z, Hurwitz S, Cheng YC, Chu CK, McClure H, Schinazi RF, Anderson KS. Mechanism of anti-human immunodeficiency virus activity of beta-D-6-cyclopropylamino-2',3'-didehydro-2',3'-dideoxyguanosine. Antimicrob Agents Chemother 2005; 49:1994-2001. [PMID: 15855524 PMCID: PMC1087621 DOI: 10.1128/aac.49.5.1994-2001.2005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To better understand the importance of the oxygen in the ribose ring of planar unsaturated nucleoside analogs that target human immunodeficiency virus (HIV), a 6-cyclopropyl-substituted prodrug of 2',3'-didehydro-2',3'-dideoxyguanosine (cyclo-d4G) was synthesized, and its cellular metabolism, antiviral activity, and pharmacokinetic behavior were studied. Cyclo-d4G had selective anti-HIV activity in primary blood mononuclear cells (PBMCs), effectively inhibiting the LAI strain of HIV-1 by 50% at 1.1 +/- 0.1 microM while showing 50% inhibition of cell viability at 84.5 microM. The antiviral activity in PBMCs was not markedly affected by mutations of methionine to valine at position 184 or by thymidine-associated mutations in the viral reverse transcriptase. Mutations of leucine 74 to valine and of lysine 65 to arginine had mild to moderate resistance (as high as fivefold). Studies to delineate the mechanism of cellular metabolism and activation of cyclo-d4G showed reduced potency in inhibiting viral replication in the presence of the adenosine/adenylate deaminase inhibitor 2'-deoxycoformycin, implying that the antiviral activity is due to its metabolism to the 2'-dGTP analog d4GTP. Intracellular formation of sugar catabolites illustrates the chemical and potentially enzymatic instability of the glycosidic linkage in d4G. Further studies suggest that cyclo-d4G has a novel intracellular phosphorylation pathway. Cyclo-d4G had a lower potential to cause mitochondrial toxicity than 2',3'-dideoxycytidine and 2',3'-didehydro-3'-deoxythymidine in neuronal cells. Also, cyclo-d4G had advantageous synergism with many currently used anti-HIV drugs. Poor oral bioavailability observed in rhesus monkeys may be due to the labile glycosidic bond, and special formulation may be necessary for oral delivery.
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Affiliation(s)
- Adrian S Ray
- Department of Pharmacology, Yale School of Medicine, New Haven, CT 06520-8066, USA
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20
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Hu R, Li L, Degrève B, Dutschman GE, Lam W, Cheng YC. Behavior of thymidylate kinase toward monophosphate metabolites and its role in the metabolism of 1-(2'-deoxy-2'-fluoro-beta-L-arabinofuranosyl)-5-methyluracil (Clevudine) and 2',3'-didehydro-2',3'-dideoxythymidine in cells. Antimicrob Agents Chemother 2005; 49:2044-9. [PMID: 15855530 PMCID: PMC1087619 DOI: 10.1128/aac.49.5.2044-2049.2005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
L-nucleoside analogs are a new class of antiviral and anticancer agents, several of which are currently used in the clinic. The phosphorylation of these agents to the triphosphate form is thought to be important for exertion of their pharmacological activities. 1-(2'-deoxy-2'-fluoro-beta-L-arabinofuranosyl)-5-methyluracil (L-FMAU; Clevudine) is a thymidine analog that is currently under phase III clinical trials as an anti-human hepatitis B virus agent. We examined the behavior of its monophosphate metabolite with human recombinant thymidylate kinase (TMPK) and showed that L-FMAU monophosphate (L-FMAUMP) is a poorer substrate than its D-configuration anomer (D-FMAUMP). The phosphorylation efficiency of l-FMAUMP is similar to that of the monophosphate of 2',3'-didehydro-2',3'-dideoxythymidine (d4T), an anti-human immunodeficiency virus analog, both of which are approximately 1% TMP. To clarify the role of human TMPK in the phosphorylation of L-FMAUMP to the diphosphate metabolite in cells, a Tet-On inducible human TMPK cell line system was established. In this system, the expression of TMPK is closely regulated in response to various concentrations of doxycycline. When the cells were treated with L-FMAU or d4T, the amounts of the diphosphate and triphosphate metabolites of these analogs were increased, in accordance with an increase in human TMPK activity in cells. In conclusion, this is the first demonstration of the behavior of TMPK toward L-FMAUMP. This study indicates that human TMPK can phosphorylate L-FMAUMP and play a critical role in L-FMAU metabolism in cells.
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Affiliation(s)
- Rong Hu
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520, USA
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21
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Liu MC, Luo MZ, Mozdziesz DE, Dutschman GE, Gullen EA, Cheng YC, Sartorelli AC. Synthesis and biological evaluation of 2',3'-didehydro-2',3'-dideoxy-9-deazaguanosine, a monophosphate prodrug and two analogues, 2',3'-dideoxy-9-deazaguanosine and 2',3'-didehydro-2',3'-dideoxy-9-deazainosine. Nucleosides Nucleotides Nucleic Acids 2005; 24:135-45. [PMID: 15822619 DOI: 10.1081/ncn-51898] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
2',3'-Didehydro-2',3'-dideoxy-9-deazaguanosine (1), its monophosphate prodrug (2), and two analogues, 2',3'-dideoxy-9-deazaguanosine (3) and 2',3'-didehydro-2',3'-dideoxy-9-deazainosine (4), have been synthesized from benzoylated 9-deazaguanosine (5). Basic hydrolysis of 5, selective protection of the 2-amino and 5'-hydroxy functions with isobutyryl and silyl groups, respectively, followed by reaction with thiocarbonyldiimidazole gave the cyclic thiocarbonate, which, upon reaction with triethyl phosphite, followed by deprotection, afforded 1. Treatment of 1 with phenyl methoxyalaninylphosphochloridate and N-methylimidazole gave 2. Catalytic hydrogenation of 1 gave 3. Hydrodediazoniation of 1 with tert-butyl nitrite and tris(trimethylsilyl)silane gave 4. Compounds 1-4 were found to be inactive against the human immunodeficiency virus and exhibited minimal to no cytotoxic activity against the L1210 leukemia, CCRF-CEM lymphoblastic leukemia, and B16F10 melanoma in vitro.
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Affiliation(s)
- Mao-Chin Liu
- Department of Pharmacology and Developmental Therapeutics Program, Cancer Center, Yale University School of Medicine, New Haven, Connecticut, USA
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22
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Kumamoto H, Haraguchi K, Tanaka H, Nitanda T, Baba M, Dutschman GE, Cheng YC, Kato K. Synthesis of (+/-)-4'-ethynyl and 4'-cyano carbocyclic analogues of stavudine (d4T). Nucleosides Nucleotides Nucleic Acids 2005; 24:73-83. [PMID: 15822615 DOI: 10.1081/ncn-51900] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The synthesis of (+/-)-4'-ethynyl (8) and 4'-cyano (9) carbocyclic analogues of the anti-HIV agent stavudine (5, d4T) is reported. The carbocyclic unit (16) was constructed from readily available beta-keto ester 10. The ethynyl or cyano group of 8 and 9 were prepared, after the introduction of thymine base to 16, by manipulation of the ester function. Evaluation of the anti-HIV activity of 8 and 9 was also carried out.
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Affiliation(s)
- Hiroki Kumamoto
- School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
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23
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Haraguchi K, Itoh Y, Takeda S, Honma Y, Tanaka H, Nitanda T, Baba M, Dutschman GE, Cheng YC. Synthesis and anti-HIV activity of 4'-cyano-2',3'-didehydro-3'-deoxythymidine. Nucleosides Nucleotides Nucleic Acids 2005; 23:647-54. [PMID: 15200028 DOI: 10.1081/ncn-120030721] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A new anti-HIV agent 4'-cyano-2',3'-didehydro-3'-deoxythymidine (9) was synthesized by allylic substitution of the 3',4'-unsaturated nucleoside 14, having a leaving group at the 2'-position, with cyanotrimethylsilane in the presence of SnCl4. Evaluation of the anti-HIV activity of 9 showed that this compound is much less potent than the recently reported 2',3'-didehydro-3'-deoxy-4'-(ethynyl)thymidine (1).
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Affiliation(s)
- Kazuhiro Haraguchi
- School of Pharmaceutical Sciences, Showa University, Shinagawa-ku, Tokyo, Japan.
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24
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Yeo H, Li Y, Fu L, Zhu JL, Gullen EA, Dutschman GE, Lee Y, Chung R, Huang ES, Austin DJ, Cheng YC. Synthesis and Antiviral Activity of Helioxanthin Analogues. J Med Chem 2005; 48:534-46. [PMID: 15658867 DOI: 10.1021/jm034265a] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of natural product analogues based on helioxanthin (2), with particular attention to modification of the lactone ring and methylenedioxy group, were synthesized and evaluated for their antiviral activities. Among them, lactam derivative 18 and helioxanthin cyclic hydrazide 28 exhibited significant in vitro antiviral activity against hepatitis B virus (EC(50) = 0.08 and 0.03 microM, respectively). Compound 18 showed the most potent antiviral activity against hepatitis C virus (55% inhibition at 1.0 microM). Compound 12, an acid-hydrolyzed product of helioxanthin cyclic imide derivative 9, was found to exhibit broad-spectrum antiviral activity against hepatitis B virus (EC(50) = 0.8 microM), herpes simplex virus type 1 (EC(50) = 0.15 microM) and type 2 (EC(50) < 0.1 microM), Epstein-Barr virus (EC(50) = 9.0 microM), and cytomegalovirus (EC(50) = 0.45 microM). Helioxanthin lactam derivative 18 also showed marked inhibition of herpes simplex virus type 1 (EC(50) = 0.29 microM) and type 2 (EC(50) = 0.16 microM). The cyclic hydrazide derivative of helioxanthin 28 and its brominated product 42 exhibited moderately potent activities against human immunodeficiency virus (EC(50) = 2.7 and 2.5 microM, respectively). Collectively, these molecules represent a novel set of antiviral compounds with unique structural features.
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Affiliation(s)
- Hosup Yeo
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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25
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Hsu CH, Liou JY, Dutschman GE, Cheng YC. Phosphorylation of Cytidine, Deoxycytidine, and Their Analog Monophosphates by Human UMP/CMP Kinase Is Differentially Regulated by ATP and Magnesium. Mol Pharmacol 2004; 67:806-14. [PMID: 15550676 DOI: 10.1124/mol.104.006098] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Human UMP/CMP kinase (cytidylate kinase; EC 2.7.4.14) is responsible for phosphorylation of CMP, UMP, and deoxycytidine monophosphate (dCMP) and also plays an important role in the activation of pyrimidine analogs, some of which are clinically useful anticancer or antiviral drugs. Previous kinetic data using recombinant or highly purified human UMP/CMP kinase showed that dCMP, as well as pyrimidine analog monophosphates, were much poorer substrates than CMP or UMP for this enzyme. This implies that other unidentified mechanisms must be involved to make phosphorylation of dCMP or pyrimidine analog monophosphates inside cells by this enzyme possible. Here, we reevaluated the optimal reaction conditions for human recombinant human UMP/CMP kinase to phosphorylate dCMP and CMP (referred as dCMPK and CMPK activities). We found that ATP and magnesium were important regulators of the kinase activities of this enzyme. Free magnesium enhanced dCMPK activity but inhibited CMPK activity. Free ATP or excess ATP/magnesium, on the other hand, inhibited dCMPK but not CMPK reactions. The differential regulation of dCMPK versus CMPK activities by ATP or magnesium was also seen in other 2'-deoxypyrimidine analog monophosphates (deoxyuridine monophosphate, 5-fluorodeoxyuridine monophosphate, 1-beta-D-arabinofuranosylcytosine monophosphate, and gemcitabine monophosphate) versus their ribose-counterparts (UMP and 5-fluorouridine monophosphate), in a similar manner. The data suggest that the active sites of human UMP/CMP kinase for dCMP and for CMP cannot be identical. Furthermore, enzyme inhibition studies demonstrated that CMP could inhibit dCMP phosphorylation in a noncompetitive manner, with Ki values much higher than its own Km values. We thus propose novel models for the phosphorylation action of human UMP/CMP kinase.
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Affiliation(s)
- Chih-Hung Hsu
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar St., SHM B226, New Haven, CT 06520, USA
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26
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Kim TE, Park SY, Hsu CH, Dutschman GE, Cheng YC. Synergistic antitumor activity of troxacitabine and camptothecin in selected human cancer cell lines. Mol Pharmacol 2004; 66:285-92. [PMID: 15266019 DOI: 10.1124/mol.66.2.285] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Troxacitabine (L-OddC) is an L-configuration deoxycytidine analog currently in phase II trials for the treatment of cancer. The cytotoxicity of L-OddC in combination with other anticancer agents has not been studied systematically. In the present study, we assessed the cytotoxic effects produced by the combinations of L-OddC and several commonly used chemotherapy drugs in a panel of cultured human cancer cell lines. Growth inhibition resulting from simultaneous exposure to two-drug combinations was determined using the methylene blue staining method. Camptothecin (CPT) and analogs exhibited additives to synergistic interactions with L-OddC by isobologram analysis. These effects were cell type-specific, with the most pronounced synergism being observed in KB oropharyngeal carcinoma and CPT-resistant KB100 cell lines. In KB cells, the total cellular uptake and DNA incorporation of L-OddC were increased by the addition of CPT. One explanation that emerged from enzyme assays of deoxycytidine kinase (dCK) and deoxycytidine monophosphate kinase (dCMPK), key enzymes involved in L-OddC phosphorylation, was that CPT protected against L-OddC-induced reduction in dCK and dCMPK activity. The resulting increase in l-OddC metabolites and incorporation into DNA was associated with enhanced L-OddC cytotoxicity. These findings will be useful in designing future clinical trials of combination chemotherapy with l-OddC and CPT analogs with the potential for a broad use against both hematological and solid tumors.
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Affiliation(s)
- Tracy E Kim
- Yale Cancer Center, Medical Oncology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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27
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Haraguchi K, Takeda S, Tanaka H, Nitanda T, Baba M, Dutschman GE, Cheng YC. Synthesis of a highly active new anti-HIV agent 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine. Bioorg Med Chem Lett 2004; 13:3775-7. [PMID: 14552777 DOI: 10.1016/j.bmcl.2003.07.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Compounds having methyl, vinyl, and ethynyl groups at the 4'-position of stavudine (d4T: 2',3'-didehydro-3'-deoxythymidine) were synthesized. The compounds were assayed for their ability to inhibit the replication of HIV in cell culture. The 4'-ethynyl analogue (15) was found to be more potent and less toxic than the parent compound stavudine.
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Affiliation(s)
- Kazuhiro Haraguchi
- School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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28
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Dutschman GE, Grill SP, Gullen EA, Haraguchi K, Takeda S, Tanaka H, Baba M, Cheng YC. Novel 4'-substituted stavudine analog with improved anti-human immunodeficiency virus activity and decreased cytotoxicity. Antimicrob Agents Chemother 2004; 48:1640-6. [PMID: 15105115 PMCID: PMC400579 DOI: 10.1128/aac.48.5.1640-1646.2004] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antiviral drug 2',3'-didehydro-3'-deoxythymidine (D4T; also know as stavudine and Zerit), which is used against human immunodeficiency virus (HIV), causes delayed toxicity (peripheral neuropathy) in long-term use. After examining a series of 2',3'-didehydro-3'-deoxy-4'-substituted thymidine (4'-substituted D4T) analogs, 4'-ethynyl D4T was found to have a fivefold-better antiviral effect and to cause less cellular and mitochondrial toxicity than D4T. The antiviral activity of this compound can be reversed by dThd but not by dCyd. The compound acted synergistically with beta-L-2',3'-deoxy-3'-thiacytidine (also known as lamivudine) and beta-L-2',3'-dideoxy-2',3'-didehydro-5-fluorocytidine (also known as elvucitabine) and additively with 2',3'-dideoxyinosine (also known as didanosine and Videx) and 3'-azido-3'-deoxythymidine (also known as Retovir and zidovudine) against HIV. 4'-Ethynyl D4T is phosphorylated by purified human thymidine kinase 1 (TK-1) from CEM cells with a faster relative V(max) and a lower K(m) value than D4T. The efficiency of TK-1 in the phosphorylation of 4'-ethynyl D4T is fourfold better than that of D4T. While D4T is broken down by the catabolic enzyme thymidine phosphorylase, the level of breakdown of 4'-ethynyl D4T was below detection. Since 4'-ethynyl D4T has increased anti-HIV activity and decreased toxicity and interacts favorably with other currently used anti-HIV drugs, it should be considered for further development as an anti-HIV drug.
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Affiliation(s)
- Ginger E Dutschman
- Department of Pharmacology, School of Medicine, Yale University, New Haven, Connecticut 06520, USA
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29
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Lam W, Li Y, Liou JY, Dutschman GE, Cheng YC. Reverse transcriptase activity of hepatitis B virus (HBV) DNA polymerase within core capsid: interaction with deoxynucleoside triphosphates and anti-HBV L-deoxynucleoside analog triphosphates. Mol Pharmacol 2004; 65:400-6. [PMID: 14742682 DOI: 10.1124/mol.65.2.400] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The use of L(-)SddC [beta-L-2',3'-dideoxy-3'-thiacytidine (lamivudine, 3TC)] for the treatment of Herpes B virus (HBV) infection is hindered by the emergence of drug-resistance associated with the L526M, L550V, and L526M/M550V mutations of the viral DNA polymerase (DP). The interactions of the anti-HBV compounds 2',3'-dideoxy-2',3'-didehydro-beta-L(-)-5-fluorode-oxycytidine and 2'-fluoro-5-methyl-beta-L-arabinofuranosyluracil triphosphate with HBV DP and its L(-)SddC-associated mutants have not been studied. The e antigen-negative variant of HBV associated with the G1896A mutation in the precore region has a high prevalence. Its effect on HBV DP is unclear. Because HBV DNA synthesis occurs in the nucleocapsid, we examined the kinetics of the reverse transcriptase activity from wild-type (wt) and mutated DPs with the wt or G1896A-mutated RNA template in the nucleocapsid. The effects of this template mutation on the activities of these L-nucleoside triphosphates were also examined. Results indicated that these DP mutations increased the Km values of deoxy-NTPs and decreased the efficiencies (Vmax/Km) of DPs. The additional L526M mutation increased the efficiency of the M550V-mutated DP but no more than that of the L526M-mutated DP. The G1896A mutation had impacts on the interactions between different DPs and deoxy-NTPs, except dCTP. It also had different impacts on the actions of the L-nucleoside triphosphates toward DPs. The L526M and M550V mutations caused a greater decrease in the Vmax using the wt RNA template compared with the G1896A-mutated template. The L526M, M550V, and L526M/M550V mutations caused varying degrees of resistance to the different M-nucleoside triphosphates.
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Affiliation(s)
- Wing Lam
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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30
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Kumamoto H, Kato K, Haraguchi K, Tanaka H, Nitanda T, Baba M, Dutschman GE, Cheng YC. Synthesis of carbocyclic analogues of 4'-ethynyl- and 4'-cyano-d4T. Nucleic Acids Symp Ser (Oxf) 2004:41-2. [PMID: 17150468 DOI: 10.1093/nass/48.1.41] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Synthesis of carbocyclic analogues of 4'-ethynyl and cyano-d4T (4 and 5) was investigated. The ethynyl or cyano group was constructed by conversion of the ester function of key intermediate 13. The carbocyclic unit 12 was prepared from readily available beta-keto ester 6.
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Affiliation(s)
- Hiroki Kumamoto
- School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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31
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Krishnan P, Gullen EA, Lam W, Dutschman GE, Grill SP, Cheng YC. Novel role of 3-phosphoglycerate kinase, a glycolytic enzyme, in the activation of L-nucleoside analogs, a new class of anticancer and antiviral agents. J Biol Chem 2003; 278:36726-32. [PMID: 12869554 DOI: 10.1074/jbc.m307052200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
l-Nucleoside analogs are a new class of clinically active antiviral and anticancer agents. The phosphorylation of these analogs from diphosphate to triphosphate metabolites is crucial for their biological action. We studied the role of 3-phosphoglycerate kinase, a glycolytic enzyme, in the metabolism of l-nucleoside analogs, using small interfering RNAs to down-regulate the amount of this enzyme in HelaS3 and 2.2.15 cells, chosen as models for studying the impact of the enzyme on the anticancer and antihepatitis B virus activities of these analogs. Decrease in the expression of 3-phosphoglycerate kinase led to a corresponding decrease in the formation of the triphosphate metabolites of l-nucleoside analogs (but not d-nucleoside analogs), resulting in detrimental effects on their activity. The enzyme is important for generating as well as maintaining the steady state levels of l-nucleotides in the cells, thereby playing a key role in the activity of l-nucleoside analogs against human immunodeficiency virus, hepatitis B virus, and cancer. This study also indicates a structure-based distinction in the metabolism of l- and d-nucleoside analogs, disputing the classic notion that nucleoside diphosphate kinases are responsible for the phosphorylation of all classes of nucleoside analog diphosphates.
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Affiliation(s)
- Preethi Krishnan
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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32
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Liou JY, Krishnan P, Hsieh CC, Dutschman GE, Cheng YC. Assessment of the effect of phosphorylated metabolites of anti-human immunodeficiency virus and anti-hepatitis B virus pyrimidine analogs on the behavior of human deoxycytidylate deaminase. Mol Pharmacol 2003; 63:105-10. [PMID: 12488542 DOI: 10.1124/mol.63.1.105] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Deoxycytidylate deaminase, catalyzing the conversion of dCMP to dUMP, is an important enzyme in the de novo synthesis of thymidine nucleotides. It also may be involved in the action, as well as the metabolism of anticancer agents. Recently, several L- and D-configuration pyrimidine deoxynucleoside analogs were found to be potent antiviral and antitumor agents. Their interaction with dCMP deaminase as a monophosphate or a triphosphate metabolite is not clear. These include D-nucleoside analogs such as beta-D-2',3'-dideoxycytidine (ddC), beta-2'-fluoro-5-methyl-arabinofuranosyluracil (FMAU), 3'-azido-2',3'-dideoxythymidine (AZT), and 2',3'-didehydro-2',3'-dideoxythymidine (D4T) as well as L-nucleoside analogs such as beta-L-dioxolane-cytidine (L-OddC), beta-L-2',3'-dideoxy-3'-thiacytidine, beta-L-2',3'-dideoxy-5'-fluoro-3'-thia-cytidine (L-FSddC), beta-L-2',3'-dideoxy-2',3'-didehydro-5-fluorocytidine, and L-FMAU. None of the L-deoxycytidine analog monophosphates act as substrates or inhibitors. Among these pyrimidine deoxynucleoside analog monophosphates, D-FMAU monophosphate (MP) is the most potent competitive inhibitor, whereas L-FMAUMP has no inhibitory activity. Interestingly, AZTMP and D4TMP also have potent inhibitory activities on dCMP deaminase. Among the dCTP and TTP analogs examined, D- and L-FMAUTP were the most potent inhibitors and had the same extent of inhibitory effect. These results suggest that a chiral specificity for the substrate-binding site may exist, but there is no chiral specificity for the regulator-binding site. This is also supported by the observation that L-OddC and L-FSddC have inhibitory activities as triphosphates but not as monophosphates. None of the D- and L-dCTP analogs activated dCMP deaminase as dCTP. The biological activities of AZT and D4T could be partially attributable to their inhibitory activity against dCMP deaminase by their phosphorylated metabolites, whereas that of ddC and the L-deoxycytidine analogs may not involve dCMP deaminase directly.
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Affiliation(s)
- Jieh-Yuan Liou
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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33
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Liou JY, Dutschman GE, Lam W, Jiang Z, Cheng YC. Characterization of human UMP/CMP kinase and its phosphorylation of D- and L-form deoxycytidine analogue monophosphates. Cancer Res 2002; 62:1624-31. [PMID: 11912132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Pyrimidine nucleoside monophosphate kinase [UMP/CMP kinase (UMP/CMPK);EC 2.7.4.14] plays a crucial role in the formation of UDP, CDP, and dCDP, which are required for cellular nucleic acid synthesis. Several cytidine and deoxycytidine analogues are important anticancer and antiviral drugs. These drugs require stepwise phosphorylation to their triphosphate forms to exert their therapeutic effects. The role of UMP/CMPK for the phosphorylation of nucleoside analogues has been indicated. Thus, we cloned the human UMP/CMPK gene, expressed it in Escherichia coli, and purified it to homogeneity. Its kinetic properties were determined. UMP and CMP proved to be far better substrates than dCMP. UMP/CMPK used all of the nucleoside triphosphates as phosphate donors, with ATP and dATP being the best donors and CTP being the poorest. Furthermore, UMP/CMPK was able to phosphorylate all of the deoxycytidine analogue monophosphates that we tested. The relative efficiency was as follows: arabinofuranosyl-CMP > dCMP > beta-L-2',3'-dideoxy-3'-thia-CMP > Gemcitabine monophosphate > beta-D-2',3'-dideoxy-CMP; beta-L-2',3'-dideoxy-2',3'-didehydro-5-fluoro-CMP; beta-L-2',3'-dideoxy-5-fluoro-3'-thia-CMP > beta-L-2',3'-dideoxy-CMP > beta-L-dioxolane-CMP. By comparing the relative V(max)/K(m) values of D- and L-form dideoxy-CMP, we showed that this kinase lacked stereoselectivity. Reducing agents, such as DTT, 2-mercaptoethanol, and thioredoxin, were able to activate this enzyme, suggesting that its activity may be regulated by redox potential in vivo. UMP/CMPK localized predominantly to the cytoplasm. In addition, 196-amino acid UMP/CMPK was the actual form of UMP/CMPK, rather than the 228-amino acid form as suggested before.
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Affiliation(s)
- Jieh-Yuan Liou
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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34
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Liu MC, Luo MZ, Mozdziesz DE, Lin TS, Dutschman GE, Gullen EA, Cheng YC, Sartorelli AC. Synthesis of halogen-substituted 3-deazaadenosine and 3-deazaguanosine analogues as potential antitumor/antiviral agents. Nucleosides Nucleotides Nucleic Acids 2001; 20:1975-2000. [PMID: 11794802 DOI: 10.1081/ncn-100108327] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Various 2-halogen-substituted analogues (38, 39, 43 and 44), 3-halogen-substituted analogues (51 and 52), and 2',3'-dihalogen-substituted analogues (57-60) of 3-deazaadenosine and 3-halogen-substituted analogues (61 and 62) of 3-deazaguanosine have been synthesized as potential anticancer and/or antiviral agents. Among these compounds, 3-deaza-3-bromoguanosine (62) showed significant cytotoxicity against L1210, P388, CCRF-CEM and B16F10 cell lines in vitro, producing IC50 values of 3, 7, 9 and 7 microM, respectively. Several 3-deazaadenosine analogues (38, 51, 57 and 59) showed moderate to weak activity against hepatitis B virus.
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Affiliation(s)
- M C Liu
- Department of Pharmacology and Developmental Therapeutics Progam, Cancer Center, Yale University School of Medicine, New Haven, Connecticut 06520-8066, USA
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35
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Liu MC, Luo MZ, Mozdziesz DE, Lin TS, Dutschman GE, Gullen EA, Cheng YC, Sartorelli AC. Synthesis and biological evaluation of L- and D-configurations of 2',3'-dideoxy-4'-C-methyl-3'-oxacytidine analogues. Bioorg Med Chem Lett 2001; 11:2301-4. [PMID: 11527719 DOI: 10.1016/s0960-894x(01)00441-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Novel L- and D-configuration 2',3'-dideoxy-4'-C-methyl-3'-oxacytidine and their 5-fluoro analogues have been synthesized from 1-benzyloxy-2-propanone and L-ascorbic acid in eight steps and evaluated for biological activity.
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Affiliation(s)
- M C Liu
- Department of Pharmacology and Developmental Therapeutics Program, Cancer Center, Yale University School of Medicine, New Haven, CT 06520-8066, USA
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36
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Kira T, Grill SP, Dutschman GE, Lin JS, Qu F, Choi Y, Chu CK, Cheng YC. Anti-Epstein-Barr virus (EBV) activity of beta-L-5-iododioxolane uracil is dependent on EBV thymidine kinase. Antimicrob Agents Chemother 2000; 44:3278-84. [PMID: 11083627 PMCID: PMC90192 DOI: 10.1128/aac.44.12.3278-3284.2000] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
beta-L-5-Iododioxolane uracil was shown to have potent anti-Epstein-Barr virus (EBV) activity (50% effective concentration = 0.03 microM) with low cytotoxicity (50% cytotoxic concentration = 1,000 microM). It exerts its antiviral activity by suppressing replicative EBV DNA and viral protein synthesis. This compound is phosphorylated in cells where the EBV is replicating but not in cells where the EBV is latent. EBV-specific thymidine kinase could phosphorylate beta-L-5-iododioxolane uracil to the monophosphate metabolite. The K(m) of beta-L-5-iododioxolane uracil with EBV thymidine kinase was estimated to be 5.5 microM, which is similar to that obtained with thymidine but about fivefold higher than that obtained with 2' fluoro-5-methyl-beta-L-arabinofuranosyl uracil, the first L-nucleoside analogue discovered to have anti-EBV activity. The relative V(max) is seven times higher than that of thymidine. The anti-EBV activity of beta-L-5-iododioxolane uracil and its intracellular phosphorylation could be inhibited by 5'-ethynylthymidine, a potent EBV thymidine kinase inhibitor. The present study suggests that beta-L-5-iododioxolane uracil exerts its action after phosphorylation; therefore, EBV thymidine kinase is critical for the antiviral action of this drug.
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Affiliation(s)
- T Kira
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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37
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Li L, Dutschman GE, Gullen EA, Tsujii E, Grill SP, Choi Y, Chu CK, Cheng YC. Metabolism and mode of inhibition of varicella-zoster virus by L-beta-5-bromovinyl-(2-hydroxymethyl)-(1,3-dioxolanyl)uracil is dependent on viral thymidine kinase. Mol Pharmacol 2000; 58:1109-14. [PMID: 11040060 DOI: 10.1124/mol.58.5.1109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A nonnaturally occurring L-configuration nucleoside analog, L-beta-5-bromovinyl-(2-hydroxymethyl)-1,3-(dioxolanyl)uracil (L-BVOddU) selectively inhibited varicella-zoster virus growth in human embryonic lung (HEL) 299 cell culture with an EC(50) of 0.055 microM, whereas no inhibition of CEM and HEL 299 cell growth or mitochondrial DNA synthesis was observed at concentrations up to 200 microM. L-BVOddU was phosphorylated by viral thymidine kinase but not by human cytosolic thymidine kinase, and the antiviral activity of this compound is dependent on the viral thymidine kinase. Unlike other D-configuration bromovinyl deoxyuridine analogs, such as E-5-(2-bromovinyl)-2'-deoxyuridine and 1-beta-arabinofuranosyl-E-5-(2-bromovinyl)uracil, this compound was metabolized only to its monophosphate metabolite. The di- or triphosphate metabolites were not detected. This suggested that the inhibitory mechanism may be unique and different from other anti-herpesvirus nucleoside analogs.
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Affiliation(s)
- L Li
- Department of Pharmacology, Yale University, New Haven, Connecticut, USA
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38
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Luo MZ, Liu MC, Mozdziesz DE, Lin TS, Dutschman GE, Gullen EA, Cheng YC, Sartorelli AC. Synthesis and biological evaluation of L- and D-configuration 1,3-dioxolane 5-azacytosine and 6-azathymine nucleosides. Bioorg Med Chem Lett 2000; 10:2145-8. [PMID: 10999490 DOI: 10.1016/s0960-894x(00)00418-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Novel L- and D-configuration dioxolane 5-azacytosine and 6-azathymine nucleosides have been synthesized and evaluated for biological activity. (-)-(2S,4S)-1-[2-(Hydroxymethyl)-1,3-dioxolan-4-yl]-5-azacytosine (6) showed significant activity against HBV, whereas the D-configuration analogue (14) has been found to exhibit potent anti-HIV activity.
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Affiliation(s)
- M Z Luo
- Department of Pharmacology and Developmental Therapeutics Program, Cancer Center, Yale University School of Medicine, New Haven, CT 06520-8066, USA
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39
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Liu MC, Luo MZ, Mozdziesz DE, Lin TS, Dutschman GE, Gullen EA, Cheng YC, Sartorelli AC. Synthesis and biological evaluation of 1,3-oxathiolane 5-azapyrimidine, 6-azapyrimidine, and fluorosubstituted 3-deazapyrimidine nucleosides. Nucleosides Nucleotides Nucleic Acids 2000; 19:603-18. [PMID: 10843496 DOI: 10.1080/15257770008035011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
(2R,5S)-5-Amino-2-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]- 1,2,4-triazine-3(2H)-one (8) and (2R,5R)-5-amino-2-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-1,2,4-tr iazine-3(2H)-one (9) have been synthesized via a multi-step procedure from 6-azauridine. (2R,5S)-4-Amino-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-1,3, 5-triazine-2(1H)-one (11) and (2R,5R)-4-amino-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]- 1,3,5-triazine-2(1H)-one (12), and the fluorosubstituted 3-deazanucleosides (19-24) have been synthesized by the transglycosylation of (2R,5S)-1-[2-[[(tert-butyldiphenylsilyl) oxy]methyl]-1,3-oxathiolan-5-yl] cytosine (2) with silylated 5-azacytosine and the corresponding silylated fluorosubstituted 3-deazacytosines, respectively, in the presence of trimethylsilyl trifluoromethanesulfonate as the catalyst in anhydrous dichloroethane, followed by deprotection of the blocking groups. These compounds were tested in vitro for cytotoxicity against L1210, B16F10, and CCRF-CEM tumor cell lines and for antiviral activity against HIV-1 and HBV.
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Affiliation(s)
- M C Liu
- Department of Pharmacology, Cancer Center, Yale University School of Medicine, New Haven, Connecticut 06520-8066, USA
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40
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Liu MC, Luo MZ, Mozdziesz DE, Lin TS, Dutschman GE, Cheng YC, Sartorelli AC. Synthesis of 2'-methylene-substituted 5-azapyrimidine, 6-azapyrimidine, and 3-deazaguanine nucleoside analogues as potential antitumor/antiviral agents. Nucleosides Nucleotides 1999; 18:55-72. [PMID: 10048223 DOI: 10.1080/07328319908045594] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
2'-Deoxy-2'-methylene-6-azauridine (5) and 2'-deoxy-2'-methylene-6-azacytidine (8) have been synthesized via a multi-step procedure from 6-azauridine. 2'-Deoxy-2'-methylene-5-azacytidine (14a) and 2'-deoxy-2'-methylene-3-deazaguanosine (19a) and their corresponding alpha-anomers (14b and 19b) have been synthesized by the transglycosylation of 3',5'-O-(1,1,3,3- tetraisopropyldisiloxane-1,3-diyl)-2'-deoxy-2'-methyleneu ridine (12) with silylated 5-azacytosine and silylated N2-palmitoyl-3-deazaguanine, respectively, in the presence of trimethylsilyl trifluoromethanesulfonate as the catalyst in anhydrous dichloroethane, followed by separation of the isomers and deprotection of the blocking groups. These compounds were tested for cytotoxicity against B16F10, L1210, and CCRF-CEM tumor cell lines and for antiviral activity against HIV-1, HSV-1, and HSV-2.
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Affiliation(s)
- M C Liu
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520-8066, USA
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41
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Chen SH, Lin S, King I, Spinka T, Dutschman GE, Gullen EA, Cheng YC, Doyle TW. Synthesis and comparative evaluation of two antiviral agents: beta-L-Fd4C and beta-D-Fd4C. Bioorg Med Chem Lett 1998; 8:3245-50. [PMID: 9873711 DOI: 10.1016/s0960-894x(98)00599-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The synthesis of beta-D-Fd4C was achieved in a stereoselective fashion from D-xylose. The antiviral activity and cytotoxicity of beta-D-Fd4C was compared with that of beta-L-Fd4C and 3TC (Lamivudine). Of the three agents compared, beta-L-Fd4C was found to be the most potent antiviral agent.
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Affiliation(s)
- S H Chen
- Vion Pharmaceuticals, Inc., Four Science Park, New Haven, CT 06511, USA
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42
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Chen SH, Wang Q, Mao J, King I, Dutschman GE, Gullen EA, Cheng YC, Doyle TW. Synthesis and biological evaluation of a series of 2'-fluorinated-2',3'-dideoxy-2',3'-didehydro-(L)-nucleosides. Bioorg Med Chem Lett 1998; 8:1589-94. [PMID: 9873396 DOI: 10.1016/s0960-894x(98)00277-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- S H Chen
- Vion Pharmaceuticals, Inc., New Haven, CT 06511, USA
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43
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Dutschman GE, Bridges EG, Liu SH, Gullen E, Guo X, Kukhanova M, Cheng YC. Metabolism of 2',3'-dideoxy-2',3'-didehydro-beta-L(-)-5-fluorocytidine and its activity in combination with clinically approved anti-human immunodeficiency virus beta-D(+) nucleoside analogs in vitro. Antimicrob Agents Chemother 1998; 42:1799-804. [PMID: 9661024 PMCID: PMC105686 DOI: 10.1128/aac.42.7.1799] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
2',3'-Dideoxy-2',3'-didehydro-beta-L(-)-5-fluorocytidine [L(-)Fd4C] has been reported to be a potent inhibitor of the human immunodeficiency virus (HIV) in cell culture. In the present study the antiviral activity of this compound in two-drug combinations and its intracellular metabolism are addressed. The two-drug combination of L(-)Fd4C plus 2',3'-didehydro-2'-3'-dideoxythymidine (D4T, or stavudine) or 3'-azido-3'-deoxythymidine (AZT, or zidovudine) synergistically inhibited replication of HIV in vitro. Additive antiviral activity was observed with L(-)Fd4C in combination with 2',3'-dideoxycytidine (ddC, or zalcitabine) or 2',3'-dideoxyinosine (ddI, or didanosine). This beta-L(-) nucleoside analog has no activity against mitochondrial DNA synthesis at concentrations up to 10 microM. As we previously reported for other beta-L(-) nucleoside analogs, L(-)Fd4C could protect against mitochondrial toxicity associated with D4T, ddC, and ddI. Metabolism studies showed that this drug is converted intracellularly to its mono-, di-, and triphosphate metabolites. The enzyme responsible for monophosphate formation was identified as cytoplasmic deoxycytidine kinase, and the K(m) is 100 microM. L(-)Fd4C was not recognized in vitro by human mitochondrial deoxypyrimidine nucleoside kinase. Also, L(-)Fd4C was not a substrate for deoxycytidine deaminase. L(-)Fd4C 5'-triphosphate served as an alternative substrate to dCTP for incorporation into DNA by HIV reverse transcriptase. The favorable anti-HIV activity and protection from mitochondrial toxicity by L(-)Fd4C in two-drug combinations favors the further development of L(-)Fd4C as an anti-HIV agent.
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Affiliation(s)
- G E Dutschman
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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44
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Pai RB, Pai SB, Kukhanova M, Dutschman GE, Guo X, Cheng YC. Telomerase from human leukemia cells: properties and its interaction with deoxynucleoside analogues. Cancer Res 1998; 58:1909-13. [PMID: 9581832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Telomerase is a unique reverse transcriptase involved in the maintenance of genomic integrity. In an attempt to understand the properties of this enzyme and to study the effect of deoxynucleoside analogues, we have isolated and partially purified telomerase from the blast cells of a patient with acute myelogenous leukemia. During the course of purification of telomerase, three characteristic forms of this enzyme activity were separated. Two processive forms and one less processive form were noted. All forms of the enzyme activities could be abolished by RNase A and proteinase K treatments, implying that they are ribonucleoproteins. The major form of telomerase was characterized with respect to divalent ion requirements, effect of salt and nonionic detergents. The Km of deoxynucleoside triphosphates was determined with a modified telomerase repeat array protocol assay. Studies with deoxynucleoside analogues indicated that 3'-azido-3'deoxythymidine triphosphate is much more inhibitory than 2',3'-dideoxy 2',3'didehydrothymidine triphosphate, and the cytidine analogue ddCTP was not inhibitory. ddGTP was the most potent inhibitor among all dideoxynucleosides studied.
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Affiliation(s)
- R B Pai
- Department of Pharmacology, Yale School of Medicine, Yale University, New Haven, Connecticut 06510, USA
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Lin TS, Luo MZ, Liu MC, Zhu YL, Gullen E, Dutschman GE, Cheng YC. Design and synthesis of 2',3'-dideoxy-2',3'-didehydro-beta-L-cytidine (beta-L-d4C) and 2',3'-dideoxy 2',3'-didehydro-beta-L-5-fluorocytidine (beta-L-Fd4C), two exceptionally potent inhibitors of human hepatitis B virus (HBV) and potent inhibitors of human immunodeficiency virus (HIV) in vitro. J Med Chem 1996; 39:1757-9. [PMID: 8627596 DOI: 10.1021/jm950836q] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- T S Lin
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520-8066, USA
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Bridges EG, Dutschman GE, Gullen EA, Cheng YC. Favorable interaction of beta-L(-) nucleoside analogues with clinically approved anti-HIV nucleoside analogues for the treatment of human immunodeficiency virus. Biochem Pharmacol 1996; 51:731-6. [PMID: 8602867 DOI: 10.1016/0006-2952(96)00056-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The combination of L(-)-2',3'-dideoxy-3'-thiacytidine (L(-)SddC, 3TC), L(-)-2',3'-dideoxy-5-fluorocytidine (L(-)FddC), or L(-)-2',3'-dideoxy-5-fluoro-3'-thiacytidine (L(-)(FTC) with 3'-azido-3'-deoxythymidine (AZT) synergistically inhibited replication of human immunodeficiency virus (HIV) in vitro. Similar synergistic activity was also obtained when these compounds were used in combination with 2',3'-didehyro-2',3'-dideoxythymidine (D4T). In terms of 2',3'- dideoxyinosime (ddI) and 2',3'-dideoxycytidine (ddC), only additive anti-HIV activity was observed. None of the beta-L(-) nucleoside analogues had additive toxicity in cell culture, and they could protect against the delayed mitochondrial toxicity associated with AZT, D4T, ddC, and ddI in drug-treated cells. Thus, combinations of beta-L(-) nucleoside analogues with any of the approved anti-HIV drugs could have a potentially beneficial outcome.
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Affiliation(s)
- E G Bridges
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06510, USA
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Lin TS, Luo MZ, Zhu JL, Liu MC, Zhu YL, Dutschman GE, Cheng YC. Synthesis of a Series of Purine 2′,3′-Dideoxy-L-Nucleoside Analogues as Potential Antiviral Agents. ACTA ACUST UNITED AC 1995. [DOI: 10.1080/15257779508009755] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Piras G, Dutschman GE, Im GJ, Pan BC, Chu SH, Cheng YC. Action of uracil analogs on human immunodeficiency virus type 1 and its reverse transcriptase. Antimicrob Agents Chemother 1995; 39:539-41. [PMID: 7537030 PMCID: PMC162575 DOI: 10.1128/aac.39.2.539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Three structural analogs of 5-ethyl-1-benzyloxymethyl-6-(phenylthio)uracil (E-BPU) inhibited human immunodeficiency virus type 1 (HIV-1) replication without cytotoxicity in vitro and were more potent than azidothymidine and were as potent as E-BPU. The target of these compounds is HIV-1 reverse transcriptase. Reverse transcriptases resistant to nevirapine (tyrosine at position 181 to cysteine) and TIBO R82150 (leucine at position 100 to isoleucine) are cross resistant to E-BPU analogs. Nevirapine- or TIBO R82150-resistant HIV-1 were cross resistant to E-BPU analogs but were inhibited at concentrations 11- to 135-fold lower than the cytotoxic doses.
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Affiliation(s)
- G Piras
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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Yen Y, Grill SP, Dutschman GE, Chang CN, Zhou BS, Cheng YC. Characterization of a hydroxyurea-resistant human KB cell line with supersensitivity to 6-thioguanine. Cancer Res 1994; 54:3686-91. [PMID: 7518343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Hydroxyurea (HU) is currently used in the clinic for the treatment of chronic myelogenous leukemia, head and neck carcinoma, and sarcoma. One of its drawbacks, however, is the development of HU resistance. To study this problem, we developed a HU-resistant human KB cell line which exhibits a 15-fold resistance to HU. The characterization of this HU-resistant phenotype revealed a gene amplification of the M2 subunit of ribonucleotide reductase (RR), increased levels of M2 mRNA and protein, and a 3-fold increase of RR activity. This HU-resistant cell line also expressed a "collateral sensitivity" to 6-thioguanine (6-TG), with a 10-fold decrease in the dose inhibiting cell growth by 50% as compared to the KB parental line. The mechanism responsible for this supersensitivity to 6-TG is believed to be related to an increasingly efficient conversion of 6-TG to its triphosphate form, which is subsequently incorporated into DNA. After passage of the resistant cells in the absence of HU, the cell line reverts. The revertant cells lose their resistance to HU and concomitantly their sensitivity to 6-TG. This phenomenon is due to the return of RR to levels comparable to that of the KB parental cell line. These observations and their relevance to cancer chemotherapy will be discussed in this paper. Our results suggest that a clinical protocol could be designed which would allow for a lower dose of 6-TG to be used by taking advantage of the increased RR activity in HU-refractory cancer patients. Two drugs which display collateral sensitivity are known as a "Ying-Yang" pair. Alternate treatment with two different Ying-Yang pairs is the rationale for the "Ying-Yang Ping-Pong" theory in cancer treatment. This rationale allows for effective cancer chemotherapy with reduced toxicity.
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Affiliation(s)
- Y Yen
- Department of Pharmacology, Yale University, New Haven, Connecticut 06510
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Lin TS, Luo MZ, Liu MC, Pai SB, Dutschman GE, Cheng YC. Synthesis and biological evaluation of 2',3'-dideoxy-L-pyrimidine nucleosides as potential antiviral agents against human immunodeficiency virus (HIV) and hepatitis B virus (HBV). J Med Chem 1994; 37:798-803. [PMID: 8145230 DOI: 10.1021/jm00032a013] [Citation(s) in RCA: 141] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Various 2',3'-dideoxy-L-cytidine,2',3'-dideoxy-L-uridine, and 3'-deoxy-L-thymidine analogues have been synthesized and evaluated in vitro as potential anti-HIV and anti-HBV agents. Coupling of 1-O-acetyl-5-O-(tert-butyldimethylsilyl)-2,3-dideoxy-L-ribofuranose (1) with silylated derivatives of 5-fluorocytosine, cytosine, 5-fluorouracil, uracil, and thymine in the presence of ethylaluminum dichloride gave the corresponding nucleosides 2, 3, 4, 5, 10, 11, 12, 16, 17, and 18 as a mixture of alpha- and beta-anomers, which were then deblocked to yield the corresponding 2',3'-dideoxy-L-5-fluorocytidine derivatives, 6 and 7, 2',3'-dideoxy-L-cytidine derivatives, 8 and 9, 2',3'-dideoxy-beta-L-fluorouridine (13), 2',3'-dideoxy-beta-L-uridine (14), and 3'-deoxy-L-thymidine derivatives, 15 and 19. Among these 2',3'-dideoxy-L-nucleoside analogues, 2',3'-dideoxy-beta-L-5-fluorocytidine (6, beta-L-FddC) was found to be the most active against HIV-1, which is approximately 3 and 4 times more active against HIV-1 in vitro than 2',3'-dideoxy-beta-D-cytidine (ddC) and 2',3'-dideoxy-beta-D-5-fluorocytidine (beta-D-FddC) with ED50 values of 0.5, 1.5, and 2 microM, respectively. The dose-limiting toxicity of ddC is severe neuropathy which may be caused by the inhibition of the synthesis of mitochondrial DNA. ddC has an IC50 value of 0.022 microM against host mitochondrial DNA synthesis. Conversely, the IC50 values for beta-L-FddC and beta-L-ddC are > 100 microM; therefore, neuropathy may not present itself to be a problem with beta-L-FddC and beta-L-ddC as chemotherapeutic agents. In addition, beta-L-FddC and 2',3'-dideoxy-beta-L-cytidine (8, beta-L-ddC) demonstrated equally potent activity against HBV in vitro by having the same ED50 value of 0.01 microM. Both beta-L-FddC and beta-L-ddC, which have an "unnatural" L-configuration in the sugar moiety, are approximately 1000 and 280 times more potent, respectively, against HBV than the D-configuration beta-D-FddC and ddC which have an ED50 values of 10 and 2.8 microM. In view of the potent antiviral activity of beta-L-FddC against both HIV-1 and HBV and potent antiviral activity of beta-L-ddC against HBV in vitro, their low cytotoxicity, and especially the negligible inhibitory effect on host mitochondrial DNA synthesis, beta-L-FddC and beta-L-ddC merit further development as potential anti-HIV and anti-HBV agents.
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Affiliation(s)
- T S Lin
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510
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