Stereoselective Synthesis and Antiviral Activity of (1E,2Z,3E)-1-(Piperidin-1-yl)-1-(arylhydrazono)-2-[(benzoyl/benzothiazol-2-oyl)hydrazono]-4-(aryl1)but-3-enes

The reaction of benzoyl hydrazine la or benzothiazole-2-carbohydrazide 1b with 2-oxo-N-arylpropanehydrazonoyl chlorides 2a-d yielded (1Z,2E)-2-[(benzoyl/benzothiazol-2-oyl)hydrazono]-N-(aryl)propanehydrazonoyl chlorides 3a-e. The reaction of 3a-c with sodium benzenesulphinate furnished sulphones 5a-c while the reaction of 5d, e with hydroxyl amine afforded hydroxomoyl derivatives 6a, b. The one-pot sterioselective reaction of N-(aryl)propanehydrazonoyl chlorides 3 with certain aromatic aldehydes in the presence of piperidine resulted in the formation of (1E,2Z,3E)-1-(piperidin-1-yl)-1-(arylhydrazono)-2-[(benzoyl/benzothiazol-2-oyl)hydrazono]-4-(aryl(1))-but-3-enes 7a-g. X-ray analysis of piperidinyl amidrazone 7g showed a conversion of its geometrical structure with respect to that of compound 3 and confirmed the stereoselectivity of the latter reaction. The piperidinyl amidrazones 7a-g possessed a significant antiviral activity against herpes simplex viruses (HSV-1). Compound 7d reduced the number of viral plaques of herpes simplex type-1 (HSV-1) by 67%, with respect to the effect of reference drug Aphidicolin.