Chirotopical properties of cisoid enones from circular dichroism (CD) and anisotropic circular dichroism (ACD) spectroscopy.

Substituted cisoid 4-en-6-one steroids with isotropically distributed and partially oriented molecules were analyzed by circular dichroism (CD) and anisotropic circular dichroism (ACD) spectroscopy, respectively. CD and ACD data supplement their respective phenomenological information. For a series of C3-substituted enones 1 to 7, the difference of CD (Delta epsilon) and ACD (Delta epsilon(A)) values, that is, Delta epsilon -Delta epsilon(A), vary in the n-* transition region in the same direction, independently of the nature and position (3 alpha or 3 beta) of the substituent.