Synthesis of new symmetrical bis-steroidal pyrazine analogues from diosgenin

Abstract

New symmetrical bis-steroidal pyrazine dimers that are cephalostatins/ ritterazines analogues have been prepared easily from a cheap, readily available natural steroid (diosgenin). These dimers were obtained by classical, condensation of α-amino ketones in order to construct the pyrazine rings. The three dimers differ in the functionalized diosgenin: (25R)-5α,6β- dihydroxy-5α-spirosta-3-one, (25R)-4,5α-epoxy-5β-spirosta-3,6- dione and (25R)-5α-hydroxy-5α-spirosta-3,6-dione respectively. © 2010 Elsevier Inc.