Isolation, Chemical Modification and In vivo Pharmacological Screening of Piperine and its Derivatives

Abstract

Piperine (1) extracted from black pepper was transformed into its derivatives piperic acid (2) and piperonal (3) with good yields (69-76%). Animal models were used to examine the compounds' in vivo peripheral as well as central analgesic and anti-inflammatory effects. In the peripheral analgesic experiment, compound 2 displayed remarkable action having writhing inhibition by 78% at 50 mg/kg dose, superior to that of 1 (74% writhing inhibition) when administered at the same dose and compared with standard diclofenac sodium (85%). Concerning central analgesic efficacy, piperonal outperformed compounds 1 and 2 at 25 mg/kg dose, with % tail-flick elongation times of 194%, 178%, and 178% at 30, 60, and 90 min, respectively. Conversely, at 50 mg/kg dose, piperic acid exhibited the highest activity, demonstrating % tail-flick elongation times of 231%, 213%, and 206% at 30, 60, and 90 min, respectively, as compared to the standard morphine (278%, 247%, and 160%) in the same duration. In anti-inflammatory property evaluation, piperonal portrayed outstanding effects with paw edema inhibitions of 57%, 66%, 76%, and 81%, respectively from 1st hour onwards, compared to standard aceclofenac (61%, 72%, 78%, and 89%) and parent compound piperine (20%, 34%, 51%, and 60%). This study suggests that piperine derivatives could act as promising leads for future drug development.