Syntheses of prodelphinidin B1, B2, and B4 and their antitumor activities against human PC-3 prostate cancer cell lines
摘要:
Total synthesis of prodelphinidin B1, B2, and B4 has been accomplished. The key step is Lewis acid-mediated equimolar condensations between an epigallocatechin and/or a gallocatechin nucleophile and an epigallocatechin and/or a gallocatechin electrophile. The antitumor effects of synthetic prodelphinidin B1-B4 against human PC-3 prostate cancer cell lines have been investigated. These compounds showed significant antitumor effects. Their activity seemed to be little bit stronger than EGCG and prodelphinidin B3, known antitumor agent. (C) 2013 Elsevier Ltd. All rights reserved.
Syntheses of prodelphinidin B1, B2, and B4 and their antitumor activities against human PC-3 prostate cancer cell lines
摘要:
Total synthesis of prodelphinidin B1, B2, and B4 has been accomplished. The key step is Lewis acid-mediated equimolar condensations between an epigallocatechin and/or a gallocatechin nucleophile and an epigallocatechin and/or a gallocatechin electrophile. The antitumor effects of synthetic prodelphinidin B1-B4 against human PC-3 prostate cancer cell lines have been investigated. These compounds showed significant antitumor effects. Their activity seemed to be little bit stronger than EGCG and prodelphinidin B3, known antitumor agent. (C) 2013 Elsevier Ltd. All rights reserved.
Tannins and related compounds. XC. 8-C-ascorbyl (-)-epigallocatechin 3-O-gallate and novel dimeric flavan-3-ols, oolonghomobisflavans A and B, from oolong tea.(3).
A chemical examination of the polypenolic constituents in commercial oolong tea has led to the isolation of a new-flavan-3-ol, two novel dimeric flavan-3-ols named oolonghomobisflavans A and B eight new proanthocyanidins, together with twenty-one known polyphenols including proanthocyanidins, hydrolyzable tannins and red pigments. On the basis of chemical and spectroscopic evidence, the flavan-3-ol has been characterized as 8-C-ascorbyl (-)-epigallocatechin 3-O-gallate (22), while oolonghomobisflavans A (26) and B (27) have been determined to be dimeric flavan-3-ols in which two units are linked through a methylene bridge at the 8, 8'- and 8, 6'-positions, respectively. The structures of the new proanthocyanidins were elucidated mainly by tannase hydrolysis and thiolytic degradtion as epicatechin-(4β→8)-epigallocatechin 3-O-gallate (29), epicatechin 3-O-gallate-(4β→8)-epigallocatechin 3-O-gallate (30), catechin-(4α→8)-epigallocatechin 3-O-gallate (31), prodelphinidin B-4 3'-O-gallate (32), epicatechin 3-O-gallate-(4β→6)-epigallocatechin 3-O-gallate (33), epigallocatechin 3-O-gallate-(4β→6)-epicatechin 3-O-gallate (34), epiafzelechin 3-O-gallate-(4β→6)-epigallocatechin 3-O-gallate (35) and prodelphinidin B-2 3'-O-gallate (36).
Total synthesis of prodelphinidin B1, B2, and B4 has been accomplished. The key step is Lewis acid-mediated equimolar condensations between an epigallocatechin and/or a gallocatechin nucleophile and an epigallocatechin and/or a gallocatechin electrophile. The antitumor effects of synthetic prodelphinidin B1-B4 against human PC-3 prostate cancer cell lines have been investigated. These compounds showed significant antitumor effects. Their activity seemed to be little bit stronger than EGCG and prodelphinidin B3, known antitumor agent. (C) 2013 Elsevier Ltd. All rights reserved.