4‐Chloro‐2,2‐disubstituted Chromen‐3‐carboxaldehyde: Synthesis of some Fused Polycyclic Heterocycles as Anti‐inflammatory, Analgesic, Anticonvulsant, and Antiparkinsonian Agents

Some new aldazino 4, pyrazolo 5, thieno 8, and thiooxopyrimidino chromenes 10 were prepared via reaction of the corresponding beta-chlorocarboxaldehyde 3 with hydrazine hydrate, mercaptoacetic acid, and thiourea, respectively. Wherever, 4-chlorochromene derivatives 2 along with 4-chlorochromen-3-carboxaldehyde derivatives 3 were prepared from the corresponding ketone 1 with Vilsmeier-Haack reagent. Some of the new products showed good anti-inflammatory, analgesic, anticonvulsant, and antiparkinsonian activities comparable to indomethacin, diclofenace, carbamazepine, and benztropine.