Three new coumarins and a new coumarin glycoside from Micromelum integerrimum / 中国天然药物

Three new coumarins, integmarins A-C (1-3), and a new coumarin glycoside, integmaside A (4) were isolated from the leaves and stems of Micromelum integerrimum. Their structures were elucidated on the basis of 1D and 2D NMR and MS data, and their absolute configurations were assigned according to the ECD data of the in situ formed transition metal complexes and comparison of experimental and calculated ECD data. Compounds 1 and 2 are two rare coumarins with butyl and propyl moieties at the C-6 position; compound 3 is a novel coumarin with a highly oxidized prenyl group, and compound 4 is a rare bisdihydrofuranocoumarin glycoside.

Natural modulators of transient receptor potential channels / 药学学报

Transient receptor potential (TRP) channels are non-selective and cation-permeable channels in the cell membrane, widely distributed in tissues and organs of human body. As biosensors, TRP channels can regulate the functions of vision, hearing, taste, pain, and touch, etc. So far, more than 100 different kinds of natural modulators targeting TRP channels have been identified from 70 species of plants or animals. In this review article, we attempt to summarize the effect of known natural active compounds on TRP channels with focuses on their sources, structures, action features and mechanisms. Hopefully this review can provide some useful information that can facilitate discovery of more specific natural modulators, and development of innovative therapeutic drugs targeting TRP channels.

Chemical constituents from Murraya euchrestifolia / 中国中药杂志

The open silica gel, ODS, and Sephadex LH-20 column chromatography, along with the semi-preparative HPLC was used to isolate and purify the chemical constituents from Murraya euchrestifolia. The structures of the isolates were elucidated by their physiochemical properties, NMR, and MS spectroscopic data, as well as comparison with literature data. Eighteen compounds were isolated from the CH2Cl2 fraction of the 95% aqueous EtOH extract of M. euchrestifolia, and their structures were identified as sakuranetin (1), eriodictyol-7,4'-dimethyl ether (2), isosakuranetin (3), 5-hydroxy-7,4'-dimethoxyflavanone (4), eriodictyol-7-methyl ether (5), lichexanthon (6), 5,6,7-trimethoxycoumarin (7), 5-hydroxy-6,8-dimethoxycoumarin (8), 8-hydroxy-6-methoxy-3-n-pentylisocoumarin (9), ethyl caffeate (10), 4-hydroxy-3,5- dimethoxycinnamic acid ethyl ester (11), methyl 3-(5'-hydroxyprenyl)-coumarate (12), (E)-coniferol (13), β-hydroxypropiovanillone (14), 3-hydroxy-7,8-didehydro-β-ionone (15), 3β-hydroxy-5α, 6α-epoxy-7-megastigmen-9-one (16), grasshopper ketone (17), and 4-hydroxy-3,5-dimethoxybenzaldehyde (18). Compounds 1-15 and 18 were first obtained from the plants of Murraya genus, and compounds 16 and 17 were isolated from M. euchrestifolia for the first time.