Steroidal versus non-steroidal forms. Part 1. Conformation of methyl cis-tetrahydro-α- and -β-santoninate

Abstract

The crystal and molecular structures of methyl cis-tetrahydro-α-(I) and -β-santoninate (II) have been determined in order to elucidate their conformations. X-Ray structure analyses reveal that both compounds have nonsteroidal conformations in the solid state. Furthermore, positive Cotton effects on the c.d. curves given by both compounds indicate the presence of non-steroidal conformations in solution.