RESUMO
The present work describes the fractionation of the crude hexane extract (EBHEX) from Calophyllum brasiliense (Clusiaceae) stem bark. Derivatization of DCM(2-9) fraction with diazomethane afforded the chromanones inophylloidic acid, isobrasiliensic acid, as well as, a mixture containing isobrasiliensic and brasiliensic acids, in the form of their more stable O-methoxy-methyl esters derivatives 1, 2, and 3, respectively. The isolation of 1 from C. brasiliense is described for the first time herein. The use of two-dimensional NMR methods ((1)H-COSY, HMQC, and HMBC) allowed the precise determination of (13)C and (1)H chemical shifts of compounds 1, 2, and 3.
Assuntos
Calophyllum/química , Cromonas/química , Espectroscopia de Ressonância Magnética/métodos , Casca de Planta/química , Extratos Vegetais/química , Ésteres , Estrutura MolecularRESUMO
In order to establish the pharmacological basis for the ethnomedicinal use of stem bark extracts of Calophyllum brasiliense Camb. in gastrointestinal affections, this study examined the effects of a dichloromethane fraction (DCMF), obtained from the hexane extract of bark, on ethanol, indomethacin and hypothermic restraint stress-induced gastric lesions in mice and rats, respectively. Oral administration of DCMF at doses ranging from 12.5-250 mg/kg significantly inhibited the development of gastric lesions in all the three test models. It caused significant decreases of the pyloric-ligation and bethanechol-stimulated gastric secretion, and also the free and total acidities. Besides, DCMF offered protection against ethanol-induced depletion of stomach wall mucus and reduction in nonprotein sulfhydryl concentration. The results indicate that DCMF from C. brasiliense possesses antisecretory, antiulcer and cytoprotective properties.