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Updated: Jul 10, 2026

Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
Synthesis of steroidal thiadiazoles from steroidal ketones
M Mushfiq1, Mahboob Alam, Mohd Shaheer Akhtar
1Department of Chemistry, AMU,Aligarh 202002, India. mmushfiq@rediffmail.com
Abstract:
Syntheses of steroidal heterocycles containing a five-membered N,S- heterocycle attached at the 6,7 positions of the B ring are reported. 5Alpha-cholestane-6-one (1), its 3beta-acetoxy- (2) and 3beta-chloro- (3) analogues reacted with semicarbazide and aqueous sodium acetate in refluxing ethanol to yield 5alpha-cholestan-6-one-semicarbazone 1a and its 3-beta-acetoxy and 3beta-chloro derivatives 2a and 3a, respectively. The reactions of 1a, 2a and 3a with thionyl chloride in dichloromethane at low temperature afforded the cyclized thiadiazole 4 and its 3beta-acetoxy- and 3beta-chloro analogues 5 and 6 in good yields.
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