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Tao L, Shi M. (CH 3) 2CuLi/Cu(OTf) 2 Mediated N- or O-Cyclization of Urea-Tethered Cyclobuta[ b]indolines. Org Lett 2019; 21:129-133. [PMID: 30571130 DOI: 10.1021/acs.orglett.8b03565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A (CH3)2CuLi/Cu(OTf)2 mediated N- or O-cyclization of urea-tethered cyclobuta[ b]indolines has been reported in this paper, giving a new synthetic protocol for the construction of pyrimido[1,6- a]indolone and cyclic imidate derivatives in moderate to good yields with a broad substrate scope under mild conditions. A plausible reaction mechanism has been also proposed on the basis of previous reports and the control experiments.
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Affiliation(s)
- Leyi Tao
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, University of Chinese Academy of Sciences , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China
| | - Min Shi
- State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, University of Chinese Academy of Sciences , Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China
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2
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Mieczkowski A, Wińska P, Kaczmarek M, Mroczkowska M, Garbicz D, Pilżys T, Marcinkowski M, Piwowarski J, Grzesiuk E. 2′-Deoxy-2′-azidonucleoside analogs: synthesis and evaluation of antitumor and antimicrobial activity. CHEMICAL PAPERS 2017. [DOI: 10.1007/s11696-017-0339-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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El Kouni MH. Pyrimidine metabolism in schistosomes: A comparison with other parasites and the search for potential chemotherapeutic targets. Comp Biochem Physiol B Biochem Mol Biol 2017; 213:55-80. [PMID: 28735972 PMCID: PMC5593796 DOI: 10.1016/j.cbpb.2017.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 06/29/2017] [Accepted: 07/03/2017] [Indexed: 12/18/2022]
Abstract
Schistosomes are responsible for the parasitic disease schistosomiasis, an acute and chronic parasitic ailment that affects >240 million people in 70 countries worldwide. It is the second most devastating parasitic disease after malaria. At least 200,000 deaths per year are associated with the disease. In the absence of the availability of vaccines, chemotherapy is the main stay for combating schistosomiasis. The antischistosomal arsenal is currently limited to a single drug, Praziquantel, which is quite effective with a single-day treatment and virtually no host-toxicity. Recently, however, the question of reduced activity of Praziquantel has been raised. Therefore, the search for alternative antischistosomal drugs merits the study of new approaches of chemotherapy. The rational design of a drug is usually based on biochemical and physiological differences between pathogens and host. Pyrimidine metabolism is an excellent target for such studies. Schistosomes, unlike most of the host tissues, require a very active pyrimidine metabolism for the synthesis of DNA and RNA. This is essential for the production of the enormous numbers of eggs deposited daily by the parasite to which the granulomas response precipitates the pathogenesis of schistosomiasis. Furthermore, there are sufficient differences between corresponding enzymes of pyrimidine metabolism from the host and the parasite that can be exploited to design specific inhibitors or "subversive substrates" for the parasitic enzymes. Specificities of pyrimidine transport also diverge significantly between parasites and their mammalian host. This review deals with studies on pyrimidine metabolism in schistosomes and highlights the unique characteristic of this metabolism that could constitute excellent potential targets for the design of safe and effective antischistosomal drugs. In addition, pyrimidine metabolism in schistosomes is compared with that in other parasites where studies on pyrimidine metabolism have been more elaborate, in the hope of providing leads on how to identify likely chemotherapeutic targets which have not been looked at in schistosomes.
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Affiliation(s)
- Mahmoud H El Kouni
- Department of Pharmacology and Toxicology, Center for AIDS Research, Comprehensive Cancer Center, General Clinical Research Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Alexeev CS, Sivets GG, Safonova TN, Mikhailov SN. Substrate specificity of E. coli uridine phosphorylase. Further evidences of high-syn conformation of the substrate in uridine phosphorolysis. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2016; 36:107-121. [PMID: 27846376 DOI: 10.1080/15257770.2016.1223306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Twenty five uridine analogues have been tested and compared with uridine with respect to their potency to bind to E. coli uridine phosphorylase. The kinetic constants of the phosphorolysis reaction of uridine derivatives modified at 2'-, 3'- and 5'-positions of the sugar moiety and 2-, 4-, 5- and 6-positions of the heterocyclic base were determined. The absence of the 2'- or 5'-hydroxyl group is not crucial for the successful binding and phosphorolysis. On the other hand, the absence of both the 2'- and 5'-hydroxyl groups leads to the loss of substrate binding to the enzyme. The same effect was observed when the 3'-hydroxyl group is absent, thus underlining the key role of this group. Our data shed some light on the mechanism of ribo- and 2'-deoxyribonucleoside discrimination by E. coli uridine phosphorylase and E. coli thymidine phosphorylase. A comparison of the kinetic results obtained in the present study with the available X-ray structures and analysis of hydrogen bonding in the enzyme-substrate complex demonstrates that uridine adopts an unusual high-syn conformation in the active site of uridine phosphorylase.
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Affiliation(s)
- C S Alexeev
- a Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia
| | - G G Sivets
- b Institute of Bioorganic Chemistry, National Academy of Sciences of Belarus , Minsk , Belarus
| | - T N Safonova
- c Bach Institute of Biochemistry, Russian Academy of Sciences , Moscow , Russia
| | - S N Mikhailov
- a Engelhardt Institute of Molecular Biology, Russian Academy of Sciences , Moscow , Russia
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Franchini S, Battisti UM, Sorbi C, Tait A, Cornia A, Jeong LS, Lee SK, Song J, Loddo R, Madeddu S, Sanna G, Brasili L. Synthesis, structural characterization and biological evaluation of 4'-C-methyl- and phenyl-dioxolane pyrimidine and purine nucleosides. Arch Pharm Res 2016; 40:537-549. [PMID: 27615010 DOI: 10.1007/s12272-016-0825-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 08/24/2016] [Indexed: 11/25/2022]
Abstract
Nucleoside analogues play an important role in antiviral, antibacterial and antineoplastic chemotherapy. Herein we report the synthesis, structural characterization and biological activity of some 4'-C -methyl- and -phenyl dioxolane-based nucleosides. In particular, α and β anomers of all natural nucleosides were obtained and characterized by NMR, HR-MS and X-ray crystallography. The compounds were tested for antimicrobial activity against some representative human pathogenic fungi, bacteria and viruses. Antitumor activity was evaluated in a large variety of human cancer cell-lines. Although most of the compounds showed non-significant activity, 23α weakly inhibited HIV-1 multiplication. Moreover, 22α and 32α demonstrated a residual antineoplastic activity, interestingly linked to the unnatural α configuration. These results may provide structural insights for the design of active antiviral and antitumor agents.
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Affiliation(s)
- Silvia Franchini
- Department of Life Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy
| | - Umberto M Battisti
- Department of Life Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy
| | - Claudia Sorbi
- Department of Life Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy
| | - Annalisa Tait
- Department of Life Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy
| | - Andrea Cornia
- Department of Chemical and Geological Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy
| | - Lak Shin Jeong
- College of Pharmacy, Seoul National University, Seoul, 151-742, Republic of Korea
| | - Sang Kook Lee
- College of Pharmacy, Seoul National University, Seoul, 151-742, Republic of Korea
| | - Jayoung Song
- College of Pharmacy, Seoul National University, Seoul, 151-742, Republic of Korea
| | - Roberta Loddo
- Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy
| | - Silvia Madeddu
- Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy
| | - Giuseppina Sanna
- Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, CA, Italy
| | - Livio Brasili
- Department of Life Sciences, University of Modena & Reggio Emilia, Via G. Campi 103, 41125, Modena, Italy.
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Synthesis of novel 4′-C-methyl-1′,3′-dioxolane pyrimidine nucleosides and evaluation of its anti-HIV-1 activity. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.10.075] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Abstract
INTRODUCTION Toxoplasma gondii, the agent that causes toxoplasmosis, is an opportunistic parasite that infects many mammalian species. It is an obligate intracellular parasite that causes severe congenital neurological and ocular disease mostly in immunocompromised humans. The current regimen of therapy includes only a few medications that often lead to hypersensitivity and toxicity. In addition, there are no vaccines available to prevent the transmission of this agent. Therefore, safer and more effective medicines to treat toxoplasmosis are urgently needed. AREAS COVERED The author presents in silico and in vitro strategies that are currently used to screen for novel targets and unique chemotypes against T. gondii. Furthermore, this review highlights the screening technologies and characterization of some novel targets and new chemical entities that could be developed into highly efficacious treatments for toxoplasmosis. EXPERT OPINION A number of diverse methods are being used to design inhibitors against T. gondii. These include ligand-based methods, in which drugs that have been shown to be efficacious against other Apicomplexa parasites can be repurposed to identify lead molecules against T. gondii. In addition, structure-based methods use currently available repertoire of structural information in various databases to rationally design small-molecule inhibitors of T. gondii. Whereas the screening methods have their advantages and limitations, a combination of methods is ideally suited to design small-molecule inhibitors of complex parasites such as T. gondii.
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Affiliation(s)
- Sandhya Kortagere
- Drexel University College of Medicine, Institute for Molecular Medicine, Department of Microbiology and Immunology, 2900, Queen Lane, PA 19129, USA.
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Theile CS, McLaughlin LW. An efficient synthetic approach to 6,5′-(S)- and 6,5′-(R)-cyclouridine. Chem Commun (Camb) 2012; 48:5587-9. [DOI: 10.1039/c2cc31597a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Avirulent uracil auxotrophs based on disruption of orotidine-5'-monophosphate decarboxylase elicit protective immunity to Toxoplasma gondii. Infect Immun 2010; 78:3744-52. [PMID: 20605980 DOI: 10.1128/iai.00287-10] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The orotidine-5'-monophosphate decarboxylase (OMPDC) gene, encoding the final enzyme of the de novo pyrimidine biosynthesis pathway, was deleted using Toxoplasma gondii KU80 knockouts to develop an avirulent nonreverting pyrimidine auxotroph strain. Additionally, to functionally address the role of the pyrimidine salvage pathway, the uridine phosphorylase (UP) salvage activity was knocked out and a double knockout of UP and OMPDC was also constructed. The nonreverting DeltaOMPDC, DeltaUP, and DeltaOMPDC DeltaUP knockout strains were evaluated for pyrimidine auxotrophy, for attenuation of virulence, and for their ability to elicit potent immunity to reinfection. The DeltaUP knockout strain was replication competent and virulent. In contrast, the DeltaOMPDC and DeltaOMPDC DeltaUP strains were uracil auxotrophs that rapidly lost their viability during pyrimidine starvation. Replication of the DeltaOMPDC strain but not the DeltaOMPDC DeltaUP strain was also partially rescued in vitro with uridine or cytidine supplementation. Compared to their hypervirulent parental type I strain, the DeltaOMPDC and DeltaOMPDC DeltaUP knockout strains exhibited extreme attenuation in murine virulence (approximately 8 logs). Genetic complementation of the DeltaOMPDC strain using a functional OMPDC allele restored normal replication and type I parental strain virulence phenotypes. A single immunization of mice with either the live critically attenuated DeltaOMPDC strain or the DeltaOMPDC DeltaUP knockout strain effectively induced potent protective immunity to lethal challenge infection. The avirulent nonreverting DeltaOMPDC and DeltaOMPDC DeltaUP strains provide new tools for the dissection of the host response to infection and are promising candidates for safe and effective Th1 vaccine platforms that can be easily genetically engineered.
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Preparation of C-5-substituted 6,5′-O-anhydrouridine by Sn–Pd transmetallation-coupling process and their use. Tetrahedron 2009. [DOI: 10.1016/j.tet.2009.09.075] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Ma GY, Zhang JZ, Yin GR, Zhang JH, Meng XL, Zhao F. Toxoplasma gondii: proteomic analysis of antigenicity of soluble tachyzoite antigen. Exp Parasitol 2009; 122:41-6. [PMID: 19545523 DOI: 10.1016/j.exppara.2009.01.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 01/21/2009] [Accepted: 01/23/2009] [Indexed: 11/26/2022]
Abstract
The obligate intracellular parasite Toxoplasma gondii is an important pathogen of humans and animals. The tachyzoite of T. gondii is the main life-cycle stage that is responsible for toxoplasmosis. Study of the antigenicity of soluble tachyzoite antigen (STAg) is important for discovery of protective antigens which will aid in the detection and prevention of toxoplasmosis. At present, no complete proteome map of T. gondii STAg is established, although a large-scale whole proteomic analysis of tachyzoites is underway. In this study, 1227 protein spots of T. gondii soluble tachyzoite antigen (STAg) were fractionated by 2-dimensional electrophoresis (2-DE) at pH range 3-10. By mass spectrometry (MS) analysis, among the separated 1227 protein spots, 426 were identified by searching the Swissport and NCBI nr databases. Two hundred and thirty of these identified spots (230/426, 54%) were demonstrated to be T. gondii protein by MS. Of the 21 Toxoplasma protein spots identified by Western blot with rabbit anti-T. gondii serum, 16 had immunoregulatory functions and five had immune defense functions. Due to multiple spots for a single protein, these 16 spots represented 11 proteins: a putative protein disulfide isomerase (PDI), heat shock protein 60 (Hsp60), a pyruvate kinase (PK), a putative glutamate dehydrogenase (GDH), a coronin, a heat shock protein 70 (Hsp70), a protein kinase C receptor 1 (RACK1), a malate dehydrogenase (MDH), a major surface antigen 1 (SAG1), an uridine phosphorylase (UPase) and a peroxiredoxin (Prx). Among the identified 11 proteins, except that the antigenicity and immunogenicity of the SAG1 has been reported and antigenicity of Hsp70 has been disputed, the remaining antigenic proteins were first identified in this study. In conclusion, we obtained nine novel types of immunogenic proteins that might be potential candidates of vaccine development for toxoplasmosis, which we will confirm in later studies.
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Affiliation(s)
- Guang-Yuan Ma
- Department of Parasitology, Shanxi Medical University, No. 56 Xinjian Nan Road, Taiyuan, Shanxi 030001, PR China
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Gaubert G, Ravindra Babu B, Vogel S, Bryld T, Vester B, Wengel J. Synthesis and RNA-selective hybridization of α-l-ribo- and β-d-lyxo-configured oligonucleotides. Tetrahedron 2006. [DOI: 10.1016/j.tet.2005.12.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Chatgilialoglu C, Ferreri C, Gimisis T, Roberti M, Balzarini J, De Clercq E. Synthesis and biological evaluation of novel 1'-branched and spironucleoside analogues. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 23:1565-81. [PMID: 15620096 DOI: 10.1081/ncn-200031391] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Novel anomeric spironucleosides and 1'-cyano-2',3'-didehydro-2',3'-dideoxyuridine, a structural analogue of known anti-HIV agents, were prepared by nucleophilic addition of organolithium reagents to 1'-cyano-2'-deoxy- and 1'-cyano-2'-deoxy-2'beta-bromo-uridine derivatives, respectively. The yield and distribution of products depended on the reaction conditions, which were studied in detail. Although none of the compounds exhibited antiviral activity, two compounds displayed cytostatic activity against both murine leukemia and human T-lymphocyte cells.
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el Kouni MH, Goudgaon NM, Rafeeq M, Al Safarjalani ON, Schinazi RF, Naguib FN. 5-phenylthioacyclouridine: a potent and specific inhibitor of uridine phosphorylase. Biochem Pharmacol 2000; 60:851-6. [PMID: 10930540 DOI: 10.1016/s0006-2952(00)00410-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
5-Phenylthioacyclouridine (PTAU or 1-[(2-hydroxyethoxy)methyl]-5-phenylthiouracil) was synthesized as a highly specific and potent inhibitor of uridine phosphorylase (UrdPase, EC 2.4.2.3). PTAU has inhibition constant (K(is)) values of 248 and 353 nM towards UrdPase from mouse and human livers, respectively. PTAU was neither an inhibitor nor a substrate for thymidine phosphorylase (EC 2.4.2.4), uridine-cytidine kinase (EC 2. 7.1.48), thymidine kinase (EC 2.7.1.21), dihydrouracil dehydrogenase (EC 1.3.1.2), orotate phosphoribosyltransferase (EC 2.4.2.10), or orotidine 5'-monophosphate decarboxylase (EC 4.1.2.23), the enzymes that could utilize the substrate (uridine or thymidine) or products (uracil or thymine) of UrdPase. Different isomers of 5-tolylthiouracil also were synthesized and tested as inhibitors of UrdPase. The meta-substituted isomer was 3- to 4-fold more potent as an inhibitor of UrdPase than the para- or ortho-substituted isomers. These data indicate that the hydrophobic pocket in the active site of UrdPase adjacent to the 5-position of the pyrimidine ring can accommodate the meta-substituted 5-phenyluracils better than the other isomers, leading to improved inhibition. Therefore, it is anticipated that the potency of PTAU can be increased further by the addition of certain hydrophobic groups at the meta position of the phenyl ring. PTAU has potential usefulness in the therapy of cancer and AIDS as well as other pathological and physiological disorders that can be remedied by the administration of uridine.
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Affiliation(s)
- M H el Kouni
- Department of Pharmacology and Toxicology and Comprehensive Cancer Center, University of Alabama at Birmingham, 35294, USA.
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Tusa G, Reed JK. The synthesis of cyclonucleotides with fixed glycosidic bond linkages as putative agonists for P2-purinergic receptors. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2000; 19:805-13. [PMID: 10960037 DOI: 10.1080/15257770008035026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Cyclonucleotides with fixed glycosidic bond linkages were investigated as possible ligands for purinoceptors in PC12 cells. P2Y2-purinoceptors were not activated by the ATP analogue, 8,2'-thioanhydroadenosine-5'-triphosphate (4) and only weakly by the UTP analogue, 2,2' -anhydrouridine-5'-triphosphate (6). However, both analogues were agonists for P2X2-purinoceptors although the potencies were approximately 30-fold less than that of the parent nucleotides.
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Affiliation(s)
- G Tusa
- Department of Chemistry, University of Toronto at Mississauga, Ontario
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Javaid ZZ, el Kouni MH, Iltzsch MH. Pyrimidine nucleobase ligands of orotate phosphoribosyltransferase from Toxoplasma gondii. Biochem Pharmacol 1999; 58:1457-65. [PMID: 10513989 DOI: 10.1016/s0006-2952(99)00231-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sixty-seven pyrimidine nucleobase analogues were evaluated as ligands of Toxoplasma gondii orotate phosphoribosyltransferase (OPRTase, EC 2.4.2.10) by measuring their ability to inhibit this enzyme in vitro. Apparent Ki values were determined for compounds that inhibited T. gondii OPRTase by greater than 20% at a concentration of 400 microM. 1-Deazaorotic acid (0.47 microM) and 5-azaorotic acid (2.1 microM) were found to bind better (8.3- and 1.9-fold, respectively) to T. gondii OPRTase than orotic acid, the natural substrate of the enzyme. Based on these results, a structure-activity relationship of ligand binding to OPRTase was formulated using uracil, barbituric acid, and orotic acid as reference compounds. It was concluded that the following structural features of pyrimidine nucleobase analogues were required or strongly preferred for binding: (i) an endocyclic pyridine-type nitrogen or methine at the 1-position; (ii) exocyclic oxo groups at the 2- and 4-positions; (iii) a protonated endocyclic pyridine-type nitrogen at the 3-position; (iv) an endocyclic pyridine-type nitrogen or methine at the 5-position; (v) an exocyclic hydrogen or fluorine at the 5-position; (vi) an endocyclic pyridine-type nitrogen or methine at the 6-position; and (vii) an exocyclic negatively charged or electron-withdrawing group at the 6-position. A comparison of the results from the present study with those from a previous study on mammalian OPRTase [Niedzwicki et al., Biochem Pharmacol 33: 2383-2395, 1984] identified four compounds (6-chlorouracil, 5-azaorotic acid, 1-deazaorotic acid, and 6-iodouracil) that may bind selectively to T. gondii OPRTase.
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Affiliation(s)
- Z Z Javaid
- Department of Biological Sciences, University of Cincinnati, OH 45221, USA
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Anionically induced formation of anomeric spironucleosides from 1′-C-cyano-2′-deoxyuridine. Tetrahedron Lett 1999. [DOI: 10.1016/s0040-4039(99)00273-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Coombs GH, Denton H, Brown SM, Thong KW. Biochemistry of the coccidia. ADVANCES IN PARASITOLOGY 1997; 39:141-226. [PMID: 9241816 DOI: 10.1016/s0065-308x(08)60046-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- G H Coombs
- Institute of Biomedical and Life Sciences, University of Glasgow, UK
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Kolb VM. Novel and unusual nucleosides as drugs. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1997; 48:195-232. [PMID: 9204688 DOI: 10.1007/978-3-0348-8861-5_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- V M Kolb
- Department of Chemistry, University of Wisconsin-Parkside, Kenosha 53141-2000, USA
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