Chemistry of renieramycins. Part 7: Renieramycins T and U, novel renieramycin-ecteinascidin hybrid marine natural products from Thai sponge Xestospongia sp.

Two new bistetrahydroisoquinoline marine natural products, renieramycins T (1) and U (2), were isolated from the Thai blue sponge Xestospongia sp. and their structures were elucidated by comparing spectral data with those of renieramycin M (3a) and ecteinascidin 770 (4a). These compounds are the first reported examples of novel ecteinascidin-renieramycin hybrid natural products. Renieramycin T (1) showed strong cytotoxicity to several human cancer cell lines, its IC₅₀ values ranging from 4.7 to 98 nM.     

Synthesis and Antitumor Activity of an Analog of Phthalascidin

Ecteinascidin 743 (Et-743) is an exceedingly potent antitumor agent isolated from the extracts of the marine tunicate Ecteinascidia turbinate1 that is currently undergoing phase Ⅱ/Ⅲ clinical trials in Europe and the United States2. As the result of its …     

An Efficient Synthetic Strategy for Construction of Functionalized Pentacyclic Skeleton of ecteinascidin-saframycin Alkaloids

Ecteinascidin 743 (Et 743, 1) is an extremely potent antitumor alkaloid isolated from the marine tunicate Ecteinascidia turbinate. It is currently undergoing phase Ⅱ/Ⅲ clinical trials1. In view of its novel structure, the lack of availability and unique mechanism of action, Et 743 has attracted extensive synthetic studies during the past decade, culminating in the first stereoselective total synthesis by E. J. Corey and co-workers in 1996 and another total synthesis by Fukuyama and co-work…     

Synthesis and cytotoxicity screening of derivatives of the simplified ecteinascidin pentacyclic skeleton as anticancer agents

A series of new ecteinascidin pentacyclic-derived compounds bearing aryl carboxylic amide side chains at C-22 have been designed and synthesized. The cytotoxicity evaluation confirmed their potent antitumor activity by use of eight different cell lines. Studies on the structure-activity relationship of them showed that the chemical structure of C-22 pendants have great effects on the tumor-killing activity. Notably, Compounds 6, 7 and 8 with benzo[b]thiophene-2-carboxamide pendants exhibited excellent broad-spectrum antitumor activity with the low IC₅₀ values of 10^?7?M.