INTERMEDIATE AND PROCESS OF PREPARATION OF ECTEINASCIDIN SUCH AS ECTEINASCIDINES-583, 597 USING SUCH INTERMEDIATE

摘要

The present invention concerns an intermediate of the following formula (I) in which R₁ and R₂ represent independently of each other a C₁-C₁₂ alkyl group, a (C₁-C₁₂ alkoxy)carbonyl group, optionally substituted by one, two or three halogen atom, a (C₂-C₁₂ alkenyloxy) carbonyl group, an acyl group, a aryl(C₁-C₁₂)alkyl group, an arylalkoxy carbonyl group, a (C₁-C₁₂ alkyl)sulfonyl group or an arylsulfonyl group, R₃ represents a O-protecting group, R₄ and R₅ represent independent ly of each other a hydrogen atom or a O-protecting group, R₆ represent a O-protecting group and R₇ represent a C₁-C₁₂ alkyl group or -OR₆ and -OR₇ form together a group -OCH₂O-. The present invention concerns also a process of preparation of the intermediate and its use for the preparation of Ecteinascidin 743 and Ecteinascidin-770.