Abstract:
Ten previously undescribed iridoid constituents, viburnshosins A-E (1-5) and viburnshosides A-E (6-10), together with one known analogue (11), were isolated from the branches of Viburnum chinshanense. Their structures were unambiguously elucidated by a comprehensive analysis of 1D and 2D NMR data, together with HRESIMS spectroscopic data. The absolute configurations of compounds 1-10 were assigned by means of the calculated ECD spectra. Interestingly, compounds 2 and 3 are the first iridoids with an unusual C-3-C-7 oxo bridge. Compounds 4, 5, and 10 displayed remarkable inhibitory effects against α-amylase (IC50: 38.42, 37.65, and 21.64 μM, respectively) and α-glucosidase (IC50: 12.97, 19.34, and 25.71 μM, respectively), comparable to those of the positive control acarbose (IC50: 39.75 and 23.66 μM, respectively). The interaction modes of compounds 4 and 10 with two enzymes were analyzed by molecular modeling.
摘要:
十种以前未描述的环烯醚萜类成分,viburnshosinsA-E(1-5)和viburnshosidesA-E(6-10),连同一个已知的类似物(11),是从燕枝的分枝中分离出来的。通过对1D和2DNMR数据的全面分析,明确地阐明了它们的结构,与HRESIMS光谱数据一起。化合物1-10的绝对构型通过计算的ECD谱指定。有趣的是,化合物2和3是第一个具有不寻常的C-3-C-7氧代桥的环烯醚萜类化合物。化合物4、5和10对α-淀粉酶表现出显著的抑制作用(IC50:38.42、37.65和21.64μM,分别)和α-葡萄糖苷酶(IC50:12.97、19.34和25.71μM,分别),与阳性对照阿卡波糖相当(IC50:39.75和23.66μM,分别)。通过分子模型分析了化合物4和10与两种酶的相互作用模式。