[A new cinnamic acid ester derivative from Liquidambaris Resina].

Twelve compounds were isolated from Liquidambaris Resina by silica gel column chromatography and thin layer chromatography. Their structures were identified on the basis of spectral data, electron capture detector data, and physicochemical properties as(2'R, 3'R)-2',3'-dihydroxy-hydrocinnamyl-(E)-cinnamate(1),(E)-cinnamyl-(E)-cinnamate(2), cinnamic acid(3), 28-norlup-20(29)-en-3-one-17ß-hydroperoxide(4), erythrodiol(5), 13ß,28-epoxy-30-hydroxyolean-1-en-3-one(6),(3ß)-olean-12-ene-3,23-diol(7), 2α,3α-dihydroxy-olean-12-en-28-oic acid(8), 28-hydroxyolean-12-en-3-one(9), 3-epi-oleanolic acid(10), 3-oxo-oleanolic acid(11), and hederagenin(12). Compound 1 was a new cinnamic acid ester derivative and compounds 2-4,6-8, and 12 were isolated from Liquidambaris Resina for the first time. Compounds 4, 5, 10, and 12 exerted inhibitory effects on the proliferation of human umbilical vein endothelial cells(HUVEC) with the IC_(50) values of(17.43±2.17),(35.32±0.61),(27.50±0.80), and(46.30±0.30) µmol·L~(-1), respectively.

Pentacyclic Triterpenes from the resin of Liquidambar formosana have anti-angiogenic properties.

Phytochemical investigation of the resin of Liquidambar formosana Hanc led to the separation and identification of five undescribed pentacyclic triterpenoids, including two lupane type, one taraxerane type, and two oleanane type triterpenoids, in addition to ten known analogues. Structures and relative or absolute configurations were elucidated by intensive spectroscopic methods, and single-crystal X-ray diffraction analysis. All isolated compounds were evaluated for their anti-angiogenic effects in vitro against VEGF-induced endothelial cell proliferation and migration in HUVECs. Among them, (5R, 8R, 9R, 10R, 13S, 14R, 17R, 18R, 19S)-17,18-epoxy-17,18-seco-28-norlupa-17- hydroxy-20 (29) -ene-3-one, (5R, 8R, 9R, 10R, 13S, 14R, 17S, 18S, 19S, 20S)-17, 20-peroxy-28- norlupa -29 -hydroxy- 3-one, 11α,12α:13ß,28-diepoxyoleanane- 3-one, 28-norlup-20 (29)-ene- 3ß,17ß-diol, liquidambaric lactone and 13,28-epoxy-11- oleanene- 3-one significantly inhibited VEGF-induced HUVECs proliferation with IC50 values ranging from 1.64 ± 0.36 to 7.06 ± 0.28 µM. In addition, they also effectively decreased VEGF-induced cell migration with IC50 values ranging from 1.57 ± 0.60 to 4.77 ± 0.62 µM. The structure-activity relationship of these compounds is discussed. The anti-angiogenic property of (5R, 8R, 9R, 10R, 13S, 14R, 17R, 18R, 19S)-17,18-epoxy-17,18-seco-28-norlupa-17- hydroxy-20 (29) -ene-3-one is mediated by the VEGFR2 - AKT signaling pathway.