Synthesis and biological acitivity of annulated pyrazoles as selective COX-2 inhibitors. I

Design, synthesis and biological evaluation of novel 1,3-diarylpyrazoles as cyclooxygenase inhibitors, antiplatelet and anticancer agents

With the aim of achieving new compounds possessing both anti-inflammatory and antiplatelet activities, we synthesized (E)-3-[3-(pyridin-3/4-yl)-1-(phenyl/sulfonylmethylphenyl)-1H-pyrazol-4-yl]acrylamides, and evaluated their COX-1 and COX-2 inhibitory and antiplatelet activities. Since COX-2 inhibitory and antiplatelet compounds have anticancer potential, we also screened their antiproliferative effects against three human cancer cell lines. Compounds 5n, 5p, 5s, 10d, 10g and 10i were determined as dual COX-2 inhibitor/antiplatelet compounds. Compound 10h appeared to be a compound that exhibited antiplatelet activity without inhibiting the COX enzyme. Compounds 5h, 10a and 10i were the most effective derivatives which displayed antiproliferative activity against Huh7, MCF7 and HCT116 cells. Particularly, compound 10i, as the compound exhibiting the highest cytotoxic, antiplatelet and COX-2 inhibitory activity, was remarkable.

1,3-Diarylcycloalkanopyrazoles and diphenyl hydrazides as selective inhibitors of cyclooxygenase-2

Novel 1,3-diarylcycloalkanopyrazoles 1, and diphenyl hydrazides 2 were identified as selective inhibitors of cyclooxygenase-2. The 1,3-diaryl substitution pattern of the pyrazole ring in 1 differentiates these compounds from most of the known selective COX-2 inhibitors that contain two aryl rings at the adjacent positions on a heterocyclic or a phenyl ring. Similarly, the two phenyl rings in 2 are also separated by three atoms. SAR of both phenyl rings in 1 and 2, and the aliphatic ring in 1 will be discussed.