Abstract
With an objective of synthesizing potent analgesic and antiinflammatory agents, here we have synthesized some novel series of pyrrole derivatives. In this ethyl-4-pyrrole-1yl-benzoate (II) was synthesized by the reaction of benzocaine (I) with 2, 5-dimethoxy tetrahydrofuran in presence of glacial acetic acid. Compound (II) on treatment with hydrazine hydrate in presence of ethanol yielded 4-pyrrole-1-yl benzoic acid hydrazide (III). Compound (III) on treatment with chloroacetyl chloride yielded N1-(2-chloroacetyl)-4-(1H-pyrrole-1-yl) benzohydrazide (IV), compound (IV) on reaction with different aromatic amines and triethylamine yielded N1-[2-(substituted phenylamino) acetyl]-4-(1H-pyrrole-1-yl)-benzohydrazide derivatives (V a-t).Structure of the synthesized compounds were confirmed on the basis of physico-chemical and spectral data (IR, 1H-NMR, 13C-NMR and Mass). All the synthesized compounds were screened for their analgesic and anti-inflammatory activity using glacial acetic acid induced writhing and carageenan induced rat paw oedema method respectively. For analgesic and antiinflammatory activities screening aspirin and diclofenac are used as standard drugs respectively. Among the synthesized compounds V a, V d, V f, V i, V k, V m, V n, V o and V p have showed good anti-inflammatory activity and compound V a, V d, V h, V k and V s showed good analgesic activity. These results are encouraging and further enhancement in the pharmacological activity can be brought about by slight modification in the ring substituent.
