Biomedical subjects
Publications and source records attributed to Yan-Ping Shi.
A new lupane type triterpenoid, 3beta, 11alpha-dihydroxy-30-norlupan-20-one and 6 known lupane triterpenoids were isolated from the petroleum ether (60-90 degrees C) extract of the whole plant of Salvia roborowskii Maxim. Their structures were elucidated by means of spectral methods including NMR and MS techniques.
The secondary metabolite composition of the gorgonian octocoral Eunicea pinta from San Andrés Island, Colombia, is described for the first time. This investigation has resulted in the isolation of eight new gamma-cembranolide-type diterpenes, namely, compounds 3-10, and a new saponin, 13, possessing a pregnene-derived aglycon. In addition, two previously known alpha-methylene-gamma-lactone cembranolides, euniolide (1) and succinolide (2), were also isolated. Their structures were determined on the basis of the results of spectroscopic analysis, X-ray diffraction analysis, and chemical conversions. The discovery of cembranolides 3-10 has prompted us to conclude that the structures proposed earlier for several uprolide-type cembranolides need revision and that a minor stereochemical correction is also in order for succinolide. Cytotoxicity of compounds 3, 4, and 13 toward various cancer cell lines and results of an antimycobacterial screening for 2, 4, and 13 also are described.
Two new sesquiterpene lactone glycosides and two new eudesmanolides, along with twelve known compounds were isolated from seeds of Carpesium macrocephalum. The structures of these new compounds were elucidated as 2alpha- O-beta- D-glucopyranosyl-5alpha, 11alpha H-eudesma-4(15)-en-12,8beta-olide ( 1), 2alpha- O-beta- D-glucopyranosyl-5alpha H-eudesma-4(15),11(13)-dien-12,8beta-olide ( 2), 2alpha-acetoxy-5alpha-hydroxy-11alpha H-eudesma-4(15)-en-12,8beta-olide ( 3) and 2alpha,5alpha-dihydroxy-11alphaH-eudesma-4(15)-en-12,8beta-olide ( 4) by spectroscopic methods including 2D NMR techniques ( (1)H- (1)H COSY, (1)H- (1)H NOESY, HMQC, HMBC) and chemical transformations. Compounds 1, 6, 8, 9 and 10 exhibited moderate antibacterial activity, while compound 4 showed appreciable cytotoxic activity against cultured SMMC-7721 (human hepatoma cell).
From the alcoholic extract of the whole plants of Serratula strangulata, two new compounds have been isolated and their structures established by spetroscopic methods as strangusin-A (1) and strangusin-B (2).