| abstract |
Indole derivatives shown by the formulae (1), (2a) and (2b) ##STR1## (wherein R 1 is a protecting group for amino group; R 2 is a protecting group for hydroxyl group; R 3 is a protecting group for hydroxyl group; R 4 is a C 1 -C 6 linear or branched lower alkyl group, or benzyl group), and pyrroloindole derivatives shown by formula (3) ##STR2## (wherein R 1 is a protecting group for amino group; R 2 is a protecting group for hydroxyl group; R 3 is a protecting group for hydroxyl group; R 4 is a C 1 -C 6 linear or branched lower alkyl group, or benzyl group), both of which are intermediates for duocarmycin SA, which is expected to be used as an anticancer agent, and derivatives thereof; and a method for producing the same. |