51
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Su B, Deng M, Wang Q. The First Enantioselective Approach to 13a-Methyl-14-hydroxyphenanthroindolizidine Alkaloids - Synthetic Studies towards Hypoestestatin 2. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201472] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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52
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Hu BL, Pi SS, Qian PC, Li JH, Zhang XG. Palladium-Catalyzed Iodine-Mediated Electrophilic Annulation of 2-(1-Alkynyl)biphenyls with Disulfides. J Org Chem 2013; 78:1300-5. [DOI: 10.1021/jo302634n] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Bo-Lun Hu
- College of
Chemistry and Materials
Engineering, Wenzhou University, Wenzhou
325035, China
| | - Sha-Sha Pi
- College of
Chemistry and Materials
Engineering, Wenzhou University, Wenzhou
325035, China
| | - Peng-Cheng Qian
- College of
Chemistry and Materials
Engineering, Wenzhou University, Wenzhou
325035, China
| | - Jin-Heng Li
- State Key
Laboratory of Chemo/Biosensing
and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Xing-Guo Zhang
- College of
Chemistry and Materials
Engineering, Wenzhou University, Wenzhou
325035, China
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53
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54
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Wang X, Fu JM, Snieckus V. Directed MetalationCross-Coupling Strategies. Total Syntheses of the Alleged and the Revised Phenanthrene Natural Product Gymnopusin. Helv Chim Acta 2012. [DOI: 10.1002/hlca.201200564] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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55
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Lee YZ, Yang CW, Hsu HY, Qiu YQ, Yeh TK, Chang HY, Chao YS, Lee SJ. Synthesis and biological evaluation of tylophorine-derived dibenzoquinolines as orally active agents: exploration of the role of tylophorine e ring on biological activity. J Med Chem 2012; 55:10363-77. [PMID: 23167614 DOI: 10.1021/jm300705j] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A series of novel tylophorine-derived dibenzoquinolines has been synthesized and their biological activity evaluated. Three assays were conducted: inhibition of cancer cell proliferation, inhibition of TGEV replication for anticoronavirus activity, and suppression of nitric oxide production in RAW264.7 cells (a measure of anti-inflammation). The most potent compound from these assays, dibenzoquinoline 33b, showed improved solubility compared to tylophorine 9a, in vivo efficacies in a lung A549 xenografted tumor mouse model and a murine paw edema model, good bioavailability, and no significant neurotoxicity (as tested by a rota-rod test for motor coordination). This is the first study to explore in detail the role of the tylophorine E ring on biological activity and very strongly suggests that tylophorine-derived dibenzoquinolines merit further development into orally active agents.
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Affiliation(s)
- Yue-Zhi Lee
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, No. 35 Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
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56
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Niphakis MJ, Gay BC, Hong KH, Bleeker NP, Georg GI. Synthesis and evaluation of the anti-proliferative and NF-κB activities of a library of simplified tylophorine analogs. Bioorg Med Chem 2012; 20:5893-900. [DOI: 10.1016/j.bmc.2012.07.044] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Revised: 07/14/2012] [Accepted: 07/24/2012] [Indexed: 01/20/2023]
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57
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Su B, Cai C, Wang Q. Enantioselective approach to 13a-methylphenanthroindolizidine alkaloids. J Org Chem 2012; 77:7981-7. [PMID: 22946502 DOI: 10.1021/jo3012122] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The first enantioselective approach to 13a-methylphenanthroindolizidine alkaloids is reported, featuring an efficient stereoselective Seebach's alkylation and Pictet-Spengler cyclization. The proposed and other three most probable structures were ruled out, indicating hypoestestatin 1 needs further assignment.
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Affiliation(s)
- Bo Su
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
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58
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Yang X, Shi Q, Lai CY, Chen CY, Ohkoshi E, Yang SC, Wang CY, Bastow KF, Wu TS, Pan SL, Teng CM, Yang PC, Lee KH. Antitumor agents 295. E-ring hydroxylated antofine and cryptopleurine analogues as antiproliferative agents: design, synthesis, and mechanistic studies. J Med Chem 2012; 55:6751-61. [PMID: 22823514 DOI: 10.1021/jm3001218] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Various E-ring hydroxylated antofine and cryptopleurine analogues were designed, synthesized, and tested against five human cancer cell lines. Interesting structure-activity relationship (SAR) correlations were found among these new compounds. The most potent compound 13b was further tested against a series of nonsmall cell lung cancer (NSCLC) cell lines in which it showed impressive antiproliferative activity. Mechanistic studies revealed that 13b is able to down-regulate HSP90 and β-catenin in A549 lung adenocarcinoma cells in a dose-dependent manner, suggesting a potential use for treating hedgehog pathway-driven tumorigenesis.
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Affiliation(s)
- Xiaoming Yang
- Natural Products Research Laboratories and ‡Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina , Chapel Hill, North Carolina 27599-7568, United States
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59
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Dong Y, Nakagawa-Goto K, Lai CY, Morris-Natschke SL, Bastow KF, Kim Y, Lee EYHP, Lee KH. Antitumor agents. 289. Design, synthesis, and anti-breast cancer activity in vivo of 4-amino-2H-benzo[h]chromen-2-one and 4-amino-7,8,9,10-tetrahydro-2H-benzo[h]chromen-2-one analogues with improved water solubility. JOURNAL OF NATURAL PRODUCTS 2012; 75:370-377. [PMID: 22304236 PMCID: PMC3311758 DOI: 10.1021/np2007878] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Previously, we reported that 4-amino-2H-benzo[h]chromen-2-one (ABO) and 4-amino-7,8,9,10-tetrahydro-2H-benzo[h]chromen-2-one (ATBO) analogues, which were developed from the lead natural product neo-tanshinlactone, are potent cytotoxic agents. In order to improve on their water solubility, the diamino analogues and related salts were designed. All synthesized compounds were assayed for cytotoxicity, and selected compounds were evaluated for in vivo anti-mammary epithelial proliferation activity in wild-type mice and mice predisposed for mammary tumors due to Brca1/p53 mutations. The new derivatives 10, 16 (ABO), 22, and 27 (ATBO) were the most active analogues, with IC(50) values of 0.038-0.085 μM in the cytotoxicity assay. Analogue 10 showed around 50-fold improved water solubility compared with the prior lead ABO compound 4-[(4'-methoxyphenyl)amino]-2H-benzo[h]chromen-2-one (3). Compounds 3, 4, 10, and 22 significantly reduced overall numbers of mammary cells, as indicated by the reduction of mammary gland branching in mutant mice. A one-week treatment with 10 resulted in 80% reduction in BrdU-positive cells in the cancer prone mammary gland. These four compounds had differential effects on cellular proliferation and apoptosis in wild-type mouse and a mouse model of human breast cancers. Compound 10 merits further development as a promising anticancer clinical trial candidate.
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Affiliation(s)
- Yizhou Dong
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
| | - Kyoko Nakagawa-Goto
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
| | - Chin-Yu Lai
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
| | - Susan L. Morris-Natschke
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
| | - Kenneth F. Bastow
- Division of Medicinal Chemistry and Natural Products, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
| | - Yoon Kim
- Department of Biological Chemistry, College of Medicine, University of California, Irvine, CA 92697, United States
| | - Eva Y.-H. P. Lee
- Department of Biological Chemistry, College of Medicine, University of California, Irvine, CA 92697, United States
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, United States
- Chinese Medicine Research and Development Center, China Medical University and Hospital, Taichung, Taiwan
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60
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Yang X, Shi Q, Yang SC, Chen CY, Yu SL, Bastow KF, Morris-Natschke SL, Wu PC, Lai CY, Wu TS, Pan SL, Teng CM, Lin JC, Yang PC, Lee KH. Antitumor agents 288: design, synthesis, SAR, and biological studies of novel heteroatom-incorporated antofine and cryptopleurine analogues as potent and selective antitumor agents. J Med Chem 2011; 54:5097-107. [PMID: 21668000 DOI: 10.1021/jm200330s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Novel heteroatom-incorporated antofine and cryptopleurine analogues were designed, synthesized, and tested against a panel of five cancer cell lines. Two new S-13-oxo analogues (11 and 16) exhibited potent cell growth inhibition in vitro (GI(50): 9 nM and 20 nM). Interestingly, both compounds displayed improved selectivity among different cancer cell lines, in contrast to the natural products antofine and cryptopleurine. Mechanism of action (MOA) studies suggested that R-antofine promotes dysregulation of DNA replication during early S phase, while no similar effects were observed for 11 and 15 on corresponding replication initiation complexes. Compound 11 also showed greatly reduced cytotoxicity against normal cells and moderate antitumor activity against HT-29 human colorectal adenocarcinoma xenograft in mice without overt toxicity.
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Affiliation(s)
- Xiaoming Yang
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, USA
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61
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Wang K, Hu Y, Liu Y, Mi N, Fan Z, Liu Y, Wang Q. Design, synthesis, and antiviral evaluation of phenanthrene-based tylophorine derivatives as potential antiviral agents. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:12337-12342. [PMID: 21058739 DOI: 10.1021/jf103440s] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A series of C9-substituted phenanthrene-based tylophorine derivatives (PBTs) were designed, synthesized, and first evaluated for their antiviral activities against tobacco mosaic virus (TMV). These compounds contain a phenanthrene core structure and can be synthesized some efficiently with excellent yields compared with tylophorine alkaloid. The bioassay results show that some of these compounds exhibited higher antiviral activity against TMV in vivo than tylophorine and commercial Ningnanmycin. Especially, compounds 3, 4, 9, 13, and 16 emerged as potential inhibitors of plant virus. These new findings demonstrate that these phenanthrene-based tylophorine derivatives (PBTs) represent another new template for antiviral studies and could be considered for novel therapy against plant virus infection.
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Affiliation(s)
- Kailiang Wang
- State Key Laboratory of Elemento-Organic Chemistry, Research Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, People's Republic of China
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62
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Yang X, Shi Q, Liu YN, Zhao G, Bastow KF, Lin JC, Yang SC, Yang PC, Lee KH. Antitumor agents 268. Design, synthesis, and mechanistic studies of new 9-substituted phenanthrene-based tylophorine analogues as potent cytotoxic agents. J Med Chem 2010; 52:5262-8. [PMID: 19645447 DOI: 10.1021/jm9009263] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nineteen new phenanthrene-based tylophorine analogues with various functional groups on the piperidine moiety were designed, synthesized, and evaluated for in vitro anticancer activity against four human tumor cell lines. Analogues 15 and 21 showed approximately 2-fold enhanced inhibitory activity as compared with our prior lead compound (PBT-1). Analogues 23 and 24 with S- and R-configured substituents, respectively, at the piperidine 3'-position exhibited comparable cytotoxicity to that of PBT-1. Furthermore, mechanistic studies to investigate the effects of the new compounds on Akt protein in lung cancer cells and the NF-kB signaling pathway suggested that the compounds may exert their inhibitory activity on tumor cells through inhibition of activation of both Akt and NF-kB signaling pathway.
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Affiliation(s)
- Xiaoming Yang
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599-7568, USA.
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63
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Lee KH. Discovery and development of natural product-derived chemotherapeutic agents based on a medicinal chemistry approach. JOURNAL OF NATURAL PRODUCTS 2010; 73:500-16. [PMID: 20187635 PMCID: PMC2893734 DOI: 10.1021/np900821e] [Citation(s) in RCA: 199] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Medicinal plants have long been an excellent source of pharmaceutical agents. Accordingly, the long-term objectives of the author's research program are to discover and design new chemotherapeutic agents based on plant-derived compound leads by using a medicinal chemistry approach, which is a combination of chemistry and biology. Different examples of promising bioactive natural products and their synthetic analogues, including sesquiterpene lactones, quassinoids, naphthoquinones, phenylquinolones, dithiophenediones, neo-tanshinlactone, tylophorine, suksdorfin, DCK, and DCP, will be presented with respect to their discovery and preclinical development as potential clinical trial candidates. Research approaches include bioactivity- or mechanism of action-directed isolation and characterization of active compounds, rational drug design-based modification and analogue synthesis, and structure-activity relationship and mechanism of action studies. Current clinical trial agents discovered by the Natural Products Research Laboratories, University of North Carolina, include bevirimat (dimethyl succinyl betulinic acid), which is now in phase IIb trials for treating AIDS. Bevirimat is also the first in a new class of HIV drug candidates called "maturation inhibitors". In addition, an etoposide analogue, GL-331, progressed to anticancer phase II clinical trials, and the curcumin analogue JC-9 is in phase II clinical trials for treating acne and in development for trials against prostate cancer. The discovery and development of these clinical trial candidates will also be discussed.
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Affiliation(s)
- Kuo-Hsiung Lee
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599-7568, USA.
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64
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Dumoulin D, Lebrun S, Couture A, Deniau E, Grandclaudon P. First Asymmetric Synthesis of Boehmeriasin A. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901404] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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65
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Synthesis and antitumor activities of phenanthrene-based alkaloids. Molecules 2009; 14:5042-53. [PMID: 20032876 PMCID: PMC6255436 DOI: 10.3390/molecules14125042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 11/25/2009] [Accepted: 12/02/2009] [Indexed: 11/16/2022] Open
Abstract
A series of phenanthrene-based tylophorine derivatives (PBTs) were synthesized and their cytotoxic activities against the H460 human large-cell lung carcinoma cell line were evaluated. Among these compounds, N-(3-hydroxy-2,6,7-tri-methoxyphenanthr-9-ylmethyl)-L-prolinol (5a), and N-(3-hydroxy-2,6,7-trimethoxy-phenanthr-9-ylmethyl)-L-valinol (9) exhibited good activities, with IC(50) values of 11.6 and 6.1 microM, respectively.
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66
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Wu CM, Yang CW, Lee YZ, Chuang TH, Wu PL, Chao YS, Lee SJ. Tylophorine arrests carcinoma cells at G1 phase by downregulating cyclin A2 expression. Biochem Biophys Res Commun 2009; 386:140-5. [DOI: 10.1016/j.bbrc.2009.05.138] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 05/30/2009] [Indexed: 10/20/2022]
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67
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Lin JC, Yang SC, Hong TM, Yu SL, Shi Q, Wei L, Chen HY, Yang PC, Lee KH. Phenanthrene-based tylophorine-1 (PBT-1) inhibits lung cancer cell growth through the Akt and NF-kappaB pathways. J Med Chem 2009; 52:1903-11. [PMID: 19284764 PMCID: PMC2670969 DOI: 10.1021/jm801344j] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Tylophorine and related natural compounds exhibit potent antitumor activities. We previously showed that PBT-1, a synthetic C9-substituted phenanthrene-based tylophorine (PBT) derivative, significantly inhibits growth of various cancer cells. In this study, we further explored the mechanisms and potential of PBT-1 as an anticancer agent. PBT-1 dose-dependently suppressed colony formation and induced cell cycle G2/M arrest and apoptosis. DNA microarray and pathway analysis showed that PBT-1 activated the apoptosis pathway and mitogen-activated protein kinase signaling. In contrast, PBT-1 suppressed the nuclear factor kappaB (NF-kappaB) pathway and focal adhesion. We further confirmed that PBT-1 suppressed Akt activation accelerated RelA degradation via IkappaB kinase-alpha and down-regulated NF-kappaB target gene expression. The reciprocal recruitment of RelA and RelB on COX-2 promoter region led to down-regulation of transcriptional activity. We conclude that PBT-1 induces cell cycle G2/M arrest and apoptosis by inactivating Akt and by inhibiting the NF-kappaB signaling pathway. PBT-1 may be a good drug candidate for anticancer chemotherapy.
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Affiliation(s)
- Jau-Chen Lin
- Institute of Biomedical Sciences, Academia Sinica, No. 128, Academia Road, Sec. 2, NanKang, Taipei, Taiwan
| | - Shuenn-Chen Yang
- Institute of Biomedical Sciences, Academia Sinica, No. 128, Academia Road, Sec. 2, NanKang, Taipei, Taiwan
| | - Tse-Ming Hong
- NTU Center of Genomic Medicine, No, 1, Jen-Ai Road, Sec. 1, Taipei, Taiwan
| | - Sung-Liang Yu
- NTU Center of Genomic Medicine, No, 1, Jen-Ai Road, Sec. 1, Taipei, Taiwan
| | - Qian Shi
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC27599, USA
| | - Linyi Wei
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC27599, USA
| | - Hsuan-Yu Chen
- Institute of Statistical Science, Academia Sinica, No. 128, Academia Road, Sec. 2, NanKang, Taipei, Taiwan
| | - Pan-Chyr Yang
- College of Medicine, National Taiwan University, No, 1, Jen-Ai Road, Sec. 1, Taipei, Taiwan
| | - Kuo-Hsiung Lee
- Natural Products Research Laboratories, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC27599, USA
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68
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Chemler SR. Phenanthroindolizidines and Phenanthroquinolizidines: Promising Alkaloids for Anti-Cancer Therapy. ACTA ACUST UNITED AC 2009; 5:2-19. [PMID: 20160962 DOI: 10.2174/157340709787580928] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The phenanthroindolizidine and phenanthroquinolizidine alkaloids, typified by tylophorine and cryptopleurine, are a family of plant-derived small molecules with significant therapeutic potential. The plant extracts have been used in herbal medicine and the isolated compounds have displayed a range of promising therapeutic activity such as anti-ameobicidal, anti-viral, anti-inflammatory and anti-cancer activity. Despite their therapeutic protential, no compounds in this class have fully passed clinical trials. Drawbacks include low in vivo anti-cancer activity, central nervous system toxicity and low natural availability. A number of biological effects of these compounds, such as protein and nucleic acid synthesis suppression, have been identified, but the specific biomolecular targets have not yet been identified. Significant effort has been expended in the synthesis and structure-activity-relationship (SAR) studies of these compounds with the hope that a new drug will emerge. This review will highlight important contributions to the isolation, synthesis, SAR and mechanism of action of the phenanthroindolizidine and pheanthroquinolizidine alkaloids.
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Affiliation(s)
- Sherry R Chemler
- The University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
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69
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An efficient one-pot approach to phenanthrene derivatives using a catalyzed tandem Ullmann-pinacol coupling reaction. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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70
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McIver A, Young DD, Deiters A. A general approach to triphenylenes and azatriphenylenes: total synthesis of dehydrotylophorine and tylophorine. Chem Commun (Camb) 2008:4750-2. [DOI: 10.1039/b811068a] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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