Abstract The behavior of ketoken gem-dithiols towards active methylene and methyl groups resulted in the formation of thiopyrano-dihydrocaumarine derivatives IIIa, b via cyclocondensation reaction between substituted 4-dihydrocyclohexanone Ia, b. N- phenylpyrazoline derivative VI was also formed through reaction of gem-dithiol IV with malonic acid followed by phenyl hydrazine. Pyridopyridazine derivative XII could also ...