Reaction of methylpheophorbides d and b with amines

A series of formyl analogs of chlorin e 6 13-amides were synthesized in high yields by reaction under mild conditions of primary and secondary amines with methylpheophorides b and d. In contrast with the secondary 13-amides, tertiary 13-amides were found as two isomers differing in the orientation of the amide plane relative to the plane of the chlorin ring. Methylpheophorbides b and d were more reactive toward the amines than methylpheophorbide a.