多籽五层龙中1个新的木栓烷型三萜

A new friedelane triterpenoid from Salacia polysperma

目的对多籽五层龙Salacia polysperma枝叶进行化学成分研究。方法采用正反相硅胶柱色谱、MCI、Sephadex LH-20柱色谱以及半制备高效液相色谱等分离手段进行分离纯化,根据1D和2D NMR、MS、IR等波谱数据和理化性质对化合物进行结构鉴定。采用分光光度法测定化合物对α-葡萄糖苷酶的抑制作用。结果从多籽五层龙枝叶90%乙醇提取物的石油醚萃取部分中分离鉴定了7个化合物,分别为3α,27,28-三羟基木栓烷(1)、kokoonol(2)、28-hydroxyfriedelan3-one-29-oic acid(3)、maytenfolone(4)、黑蔓醇酯乙(5)、α-香树脂素(6)、赤桐甾醇(7)。化合物3表现出较好的α-葡萄糖苷酶抑制活性,半数抑制浓度(median inhibition concentration,IC50)值为15.1μmol/L。化合物1、2、4也具有一定的α-葡萄糖苷酶抑制作用,IC50值分别为57.8、39.4、27.6μmol/L,其余化合物在100μmol/L的较高浓度下未显示出对α-葡萄糖苷酶的抑制作用。结论化合物1为1个新的木栓烷型三萜,命名为多籽五层龙醇(polysperol);所有化合物均为首次从该植物中分离得到。化合物3具有较好的α-葡萄糖苷酶抑制活性。

Objective To investigate the chemical constituents of branches and leaves of Salacia polysperma.Methods The compounds were isolated and purified by positive and negative phase silica gel column chromatography,MCI,Sephadex LH-20 column chromatography and semi-preparative high performance liquid chromatography.Their structures were identified by 1D,2D NMR,MS and IR spectra and physicochemical properties.The inhibitory effect of these compounds onα-glucosidase was determined by spectrophotography.Results A total of seven compounds were isolated from the petroleum ether extract part of 90%EtOH extract of branches and leaves of S.polysperma.Their structures were identified as 3α,27,28-trihydroxy friedelane(1),kokoonol(2),28-hydroxyfriedelan-3-one-29-oic acid(3),maytenfolone(4),regelindiol B(5),α-amyrin(6),and clerosterol(7).Compound 3 exhibited moderateα-glucosidase inhibitory activity with a median inhibition concentration(IC50)value of 15.1μmol/L.Compounds 1,2 and 4 showed slightα-glucosidase inhibitory activities with IC50 values of 57.8,39.4,and 27.6μmol/L,respectively.The other compounds displayed none inhibitory activity even in a high concentration of 100μmol/L.Conclusion Compound 1,named polysterol,was a new friedelane type triterpenoid and all compounds were isolated from this medicinal plant for the first time.Compound 3 showed moderateα-glucosidase inhibitory activity.