Synthesis and antiviral evaluation of novel 5-(N-Aryl-aminomethyl-1,3,4-oxadiazol-2-yl)hydrazines and their sugars, 1,2,4-triazoles, tetrazoles and pyrazolyl derivatives.

A number of new N-arylaminomethyl-1,3,4-oxadiazole derivatives 2, 3a,b, and 9-12a,b were prepared. Sugar (5-N-arylaminomethyl-1,3,4-oxadiazol-2-yl) hydrazones 4-6a,b were synthesized by the reaction of the hydrazino derivatives 3a,b with the corresponding monosaccharides. The novel acyclo-C-nucleosides 7, 8a,b were prepared by heterocyclization of the sugar hydrazones 4, 5a,b with acetic anhydride. A number of the synthesized compounds were tested for their antiviral activity against herpes simplex virus type-1 (HSV-1) and hepatitis-A virus (HAV, MBBcell culture-adapted strain). The results revealed that the sugar hydrazones 6a,b showed higher antiviral activity compared to the other hydrazones and their acetylated derivatives.

Conversion of 3-arylazo-5-phenyl-2(3H)-furanones into other heterocycles of anticipated biological activity.

3-arylazo-5-phenyl-2(3H)-furanones 3 were prepared and converted into a variety of heterocyclic systems of synthetic and biological importance. Hydrazine hydrate reacted with furanones as nucleophiles and gave the corresponding acid hydrazides 4. The latter products were used as starting materials for the synthesis of 1,3,4-oxadiazoles 6, 9, and the 1,2,4-triazoles 8. Evaluation of the antiviral activity of selected compounds obtained was performed using two viruses: HAV and HSV-1. Some of the tested compounds showed promising activities.