Synthesis of Some Heterocycles of Expected Biological Activity Through the Action of Isatin-3-Thiosemicarbazone on Acetylenic Ketones and Esters

Abstract

Isatin-3-thiosemicarbazone ( 1 ) reacted with 1-aryl-3-phenylprop-2-yn-1-ones ( 2a-c ) in n-butanol to give 4-aryl-6-phenyl-2-[2-oxo-2H,3H-benzo(b) pyrrolidine-3-iminyl]-imino-2H-1,3-thiazines ( 3a-c ). Similar treatment of 1 with acetylenic esters ( 4a-c ) gave the 6-substituted derivatives of 2-imino-3-[2-oxo-2H,3H-benzo(b)pyrrolidine-3-iminyl]-2,3-dihydro-4-oxo-1,3-thiazine ( 5a-c ). Treatment of 1 with 4a-c in the presence of sodium ethoxide in ethanol gave the 6-substituted derivatives of 3-[2-oxo-2H,3H-benzo(b)pyrrolidine-3-iminyl]-4-oxo-2-thioxo-1,2,4-trihydropyrimidine ( 6a-c ). However, when 1 was refluxed with 1-p-chlorophenyl-3-phenylprop-2-yn-1-one ( 2b ) in ethanol it gave a mixture of 2,4,6-tris[2-oxo-2H,3H-benzo(b)pyrrolidine-3-iminyl] amino-1,3,5-triazine ( 7 ) and Z,Z-3,3'-thiodi(1-p-chlorophenyl-3-phenylprop-2-en-1-one) ( 8 ). The aziridine imine derivative ( 9 ) and the pyrazole derivatives ( 10a and b ) were the only isolated products upon treatment of 3c , 6a , and 6c and 3a and 3b with hydrazine hydrate, respectively. Structures of all new compounds are evidenced by microanalytical and spectral data.