Unexpected ring opening of pyrazolines with activated alkynes: synthesis of 1-pyrazole-4,5-dicarboxylates and chromenopyrazolecarboxylates.

1-Pyrazole-4,5-dicarboxylates and chromenopyrazole carboxylates were prepared by reacting pyrazolines with activated alkynes under neat conditions without a catalyst. The products were formed unexpected ring opening of pyrazolines with the elimination of styrene/ethylene. These types of transformations are unknown and the products formed were confirmed using their spectral/analytical data.

Synthesis and Anti-proliferative Activity of 4H-Chromone Based Phenylhydrazones, Pyrazolecarboxylates and Pyrazolylmethanones.

Series of 4H-chromone-based hydrazones 3a-z, pyrazolecarboxylates 5a-x and pyrazolylmethanones 6a-u were prepared and screened for their anti-proliferative activity on A549, HeLa, DU145 and MDAMB 231 cell lines. The hydrazone compound 3s with a chloro substituent on the chromanone moiety and a methoxy group on the phenyl ring displayed promising activity on A549, HeLa and DU145 cell lines. The compound 5p with a bromo substituent on the chromanone moiety and a methyl group on the phenyl ring displayed potent activity on DU145.