title: Syntheses and ultraviolet absorption of aza-steroids.
abstract: A series of aza-steroids was synthesized containing chromophoric groups, such as a, beta-unsaturated ketones and doubly unsaturated conjugated and monoconjugated heteroannular dienones with the heteroatom in the D ring at the 20 and 17a positions. The effect of an appositely placed electronegative center in these molecules upon their ultraviolet absorptions was studied. In order to obtain a basis for the observed spectral changes, the corresponding carbocyclic compounds were also synthesized. The maximum absorptions of the aza-steroids were hypsochromically shifted relative to the carbocyclic compounds in all cases (n=8). The displacement caused by the electronegative center on absorption maximum of the chromophores is, however, highly dependent on its location within the molecules.
mesh_terms: D001378:Azasteroids / Q000032:analysis* / Q000138:chemical synthesis; D002192:Canrenone / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D008722:Methods; D013056:Spectrophotometry, Ultraviolet; D013260:Steroids, Heterocyclic / Q000032:analysis*; D013739:Testosterone / Q000032:analysis
chemical_list: D001378:Azasteroids; D013260:Steroids, Heterocyclic; D013739:Testosterone; D002192:Canrenone