Synthesis and evaluation of antidepressant and sedative activities of some benzo[b] thiophenes.

Abstract

The coupling reaction of 2-diazo-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene 2 with the 2-aminoprop-1-ene-1,1,3-tricarbonitrile 3 gave the hydrazone derivative 4. Compound 4 underwent ready cyclization to give the pyridazine derivative 5. The Reaction of 4 with hydrazines gave pyrazole derivatives 6a,b. On the other hand, the reaction of 4 with active methylene reagents gave the pyridazine derivatives 7a,b. The latter products were cyclized into the pyrido[3,2-c]pyrimidine derivatives 8a and 8b, respectively. The reaction of 4 with phenylisothiocyanate gave the 1,2,4-triazine derivative 9. The antidepressant and sedative activities of the newly synthesized products were measured.