Calphostins, novel and specific inhibitors of protein kinase C. II. Chemical structures

Abstract

The structures of new antitumor antibiotics, calphostins (UCN-1028) A, B, C, D and I, which are specific and potent inhibitors of protein kinase C, were determined by spectral and chemical studies. All of the antibiotics have a 3, 10-perylenequinone skeleton and calphostin D was revealed to be an antipode of isophleichrome. © 1989, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.