| abstract |
A method for producing compounds with a condensed cyclic structure of the formula (XIV) is described. These products are ecteinascidins, which have a spiroamine-1,4-bridge. This method involves the formation of a 1,4-bridge using a (1-labile) -10-hydroxy- (18-protected hydroxy) di-6,8-en-5-one-fused cyclic compound. After the formation of the 1,4-bridge, the C-18 protection is removed before the introduction of spiroamine. |