PEG mediated synthesis and pharmacological evaluation of some fluoro substituted pyrazoline derivatives as antiinflammatory and analgesic agents.

A new series of fluoro substituted pyrazoline derivatives 5a-g and 6a-g were synthesized in good to excellent yield from the corresponding pyrazole chalcones, 4a-g, by using polyethylene glycol-400 (PEG-400) as an alternative reaction medium. The newly synthesized compounds were characterized and screened for their in vivo antiinflammatory and analgesic activity. Compounds 5g and 6g were found to be more potent than standard drug Diclofenac and six other compounds 5b, 5c, 5f, 6b, 6c and 6f showed significant antiinflammatory activity as compared to standard drug. Compounds 5c, 5d, 5e, 5f, 6c, 6d, 6e and 6f showed significant analgesic activity as compared to standard drug Aspirin.