Synthesis and study of some 4-aza and 17a-azasteroidal isoxazoles

4-Aza-5 alpha-androstano[2,3-6]isoxazole 4 and 17a-aza-D-homo-5-androsteno[ 17, 16-c]isoxazole 7 have been prepared by treating alpha,beta-unsaturated- beta-chloroaldehydes 3 and 6 [1, 2] with hydroxylamine hydrochloride in pyr idine. [16,17-d]Isoxazole derivatives 4 and 8 were found to be unstable in most of the organic solvents. beta-Cyanolactam derivatives 5 and 9 have als o been prepared in both the series. (C) 1999 Editions scientifiques et medi cales Elsevier SAS.