Studies on chemical constituents from stem bark of Trewia nudiflora / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents from the stem bark of Trewia nudiflora.</p><p><b>METHOD</b>The chemical constituents were isolated by silica gel and sephadex LH - 20 column chromatography, and the structures were elucidated by means of spectral analysis.</p><p><b>RESULT</b>Ten compounds were obtained from EtOAc fraction of EtOH extract and identified as stigmast-4-en-6beta-ol-3-one (1), stigmast-4-en-6alpha-ol-3-one (2), 7beta-hydroxysitosterol (3), 7alpha-hydroxysitosterol (4), schleicheol 2 (5), taraxerone (6), abbeokutone (7), beta-hydroxypropiovanillone (8), o-vanillyl alcohol (9), glycerol monopalmitate (10).</p><p><b>CONCLUSION</b>Compounds 1-5 and 7-9 were isolated from this plant for the first time.</p>

Anti-gastric ulcer sesquiterpene lactone glycosides from Crepis napifera / 药学学报

<p><b>AIM</b>The anti-gastric ulcer constituents from the roots of Crepis napifera (Franch) Babc (Compositae) were studied.</p><p><b>METHODS</b>Solvent partition, Si gel and Rp-18 column chromatography, crystallization and spectral methods were used to extract, isolate and identify two compounds. The activity of compound 1 was tested on the rat stomach by determining the effect on aspirin-induced gastric lesions and on histamine-stimulated gastric acid secretion.</p><p><b>RESULTS</b>Two sesquiterpene lactone glycosides, taraxinic acid-1'-O-beta-D-glucopyranoside (1) and 11,13-dihydro-taraxinic acid-1'-O-beta-D-glucopyranoside (2) were obtained. Compound 1 at the dose of 80 mg.kg-1 p.o. inhibited significantly the development of aspirin-induced gastric lesions in the rat and at an i.v. dose of 70 mg.kg-1 did not affect histamine-stimulated gastric acid secretion in the lumen-perfused rat stomach.</p><p><b>CONCLUSION</b>Compound 1 is the active component of the plant which protects gastric mucosa and exhibits anti-gastric ulcer action.</p>