Steroids 2012-04-01

Regioselective cleavage of 22-oxo-23-spiroketals. Novel cholestanic frameworks with pyranone and cyclopentenone E rings on the side chain.

Yliana López, León Rodríguez, Rosa E del Río, Norberto Farfán, Jacek W Morzycki, Rosa Santillan

Index: Steroids 77(5) , 534-41, (2012)

Full Text: HTML

Abstract

The regioselective opening of the F ring of 22-oxo-23-spiroketals using a saturated solution of HCl in acetic anhydride yielded novel cholestanic frameworks with pyranone or cyclopentenone E rings. The structures of the new derivatives of sarsasapogenin, diosgenin and hecogenin thus obtained were established using one and two dimensional (1)H, (13)C experiments (DEPT, COSY, HETCOR, HMBC, ROESY, and NOESY). The X-ray analysis for compound 11b confirmed the 23R configuration for the new stereogenic center.Copyright © 2012 Elsevier Inc. All rights reserved.