Potent and selective PKC inhibitory 5-membered ring analogs of balanol with replacement of the carboxamide moiety

Balanol ((−)-1) is a potent protein kinase inhibitory natural product isolated from the fungus Verticillium balanoides. The lack of cellular activity and protein kinase C selectivity in balanol has prompted a search for analogs that incorporate these properties. This paper describes the synthesis and biological activity of such compounds with substitution similar to balanol, but with a single atom bridge in place of the carboxamide moiety.