Synthetic approaches to 9-azasteroids

Abstract

An account is given of total syntheses of azasteroids, syntheses of 4-piperidones, and also syntheses of 2-quinolizidones.
l,2,3,4,5,6-Hexahydro-3-oxo-4aH-benzo[c]quinolizine was prepared and methylation shown to occur in the 2-position which was of no further synthetic value. 4-Cyano-l,2,3,4,5,6-hexahydro-3-oxo- 4aH-benzo[c]quinolizine was prepared and alkylated with bromo-acetone. Attempts to cyclise the product to produce the 9-azasteroid system
were unsuccessful.
l-Phenyl-4-piperidone was synthesised by a method giving a higher yield than reported in the literature, and some alkylation reactions carried out on it.
Some reactions of compounds containing reactive hydrogens with quinoline-1-oxide in the presence of acetic anhydride are reported.
Some 2-cyclopentyl quinoline derivatives are prepared by the action of cyclopentanone derivatives containing active hydrogens on quinoline-1-oxide in the presence of acetic anhdride or quinoline in the presence of acid chlorides. Attempts to construct ring C of the
9-azasteroid system from the 2-cyclopentyl quinoline derivatives have been investigated.

Citation

(1968). Synthetic approaches to 9-azasteroids