Sunil K. Banerjee

Anti‐inflammatory activity of oleanolic acid in rats and mice

Abstract— Oleanolic acid displayed anti‐inflammatory activity in carrageenan and dextran‐induced oedema in rats. It elicited marked anti‐arthritic action in adjuvant‐induced polyarthritis in rats and mice and in formaldehyde‐induced arthritis in rats. Oleanolic acid checked the inflammation‐induced increased serum transaminase levels. It reduced exudate volume and inhibited leucocyte infiltration in carrageenan‐induced pleurisy in rats. It is devoid of any analgesic, antipyretic or ulcerogenic action. Oleanolic acid did not affect the parturition time in pregnant rats or castor oil‐induced diarrhoea in rats. Oral LD50 was found to be greater than 2 g kg−1 in mice and rats.

Actions of some flavonoids on specific and non-specific immune mechanisms

The immunomodulatory activity of some flavonoids on antigen specific humoral and cell mediated immune responses and complement-mediated hemolysis has been investigated and compared with that of levamisole. Flavanone, 6-methoxyflavanone, 7-methoxyflavanone and bavachinin enhanced the sheep erythrocyte (SRBC), induced primary and secondary humoral immune responses in mice, and 6-hydroxyflavanone, 7-hydroxyflavanone and rutin inhibited primary response. Levamisole slighly stimulated the primary and suppressed the secondary response. All the flavonoids tested decreased the manifestation of SRBC induced delayed type hypersensitivity reaction and showed no effect on classical or alternative pathway dependent hemolysis. The studies revealed the significant immunomodulatory potential of these flavonoids, methoxy derivatives having immunostimulatory activity and hydroxy derivatives immunosuppressive properties.

New coumarins from Seseli sibiricum

Abstract Three new coumarins, sesebrin(7-methoxy-5-[3-methylbut-2-enyloxy]-8-[3-methyl-2,3-epoxybutyl] coumarin), sesebrinol(7-methoxy-5-[3-methylbut-2-enyloxy]-8-[3-methyl-2,3-dihydroxybutyl] coumarin) and sibiricol (7-methoxy-5-hydroxy-8-[3-methylbut-2-enyl] coumarin) have been isolated from the roots of Seseli sibiricum , in addition to sitosterol and 7 known coumarins, isobergapten, bergapten, phellopterin, sibiricin, coumurrayin, osthenol and meranzin hydrate.

New coumarins from the umbels of Seseli sibiricum.

Abstract Three new coumarins, seselinal, sesibiricol and sibirinol, and 12 known coumarins have been isolated from the umbels of Seseli sibiricum. The new coumarins have been characterized as 5, 7-dimethoxy-8-(2-methyl-2-formylpropyl)-2H-1-benzopyran-2-one, 5-(3-methylbut-2-enyloxy)-7-methoxy-8-(2-hydroxy-3-methylbut-3-enyl)-2H-1-benzopyran-2-one and 5,7-dimethoxy-8-(2-hydroxy-3-methylbut-3-enyl)-2H-1-benzopyran-2-one,respectively. The known ones were identified as sesibiricin, isosibiricin, osthol, coumurrayin, sesebrin, sesebrinol, sibiricin, imperatorin, bergapten, xanthotoxin, isopimpinellin and mexoticin.

Antiinflammatory actions of Euphorbia splendens extract

Petroleum ether extract of the aerial parts of plant Euphorbia splendens (PEE) was screened for antiinflammatory activity using carrageenan induced oedema test in rats and mice as an acute and adjuvant arthritis as chronic models. Oral administration of PEE caused significant inhibition of oedema in these tests and produced inhibition of leucocyte migration and exudate volume in the affected tissues. The oral LD50 in both rats and mice was approximately 1250 mg/kg.

Sesebrinic acid, a cinnamic acid derivative from Seseli sibiricum

Abstract A new cinnamic acid, sesebrinic acid, was isolated from the aerial parts of Seseli sibiricum , its structure was elucidated by chemical and spectral data and hemisynthesis. A number of its analogues were also synthesized.

A simple one-step synthesis of phenyl ethers from phenyl acetates

Phenyl acetates when refluxed with alkyl halides in acetone solution in the presence of a crown ether and anhydrous potassium carbonate undergo alkylation yielding phenyl ethers.