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A newent-kaurane diterpenoid, 3α, 14β, 16α-trihydroxy-ent-kaurane (1), together with seven known diterpenoids (2–8), was isolated from the leaves ofIsodon japonica. Their structures were elucidated by spectroscopic methods, including 1D and 2D NMR experiments, IR, HR-ESI-MS and X-ray crystallographic analysis. [ABSTRACT FROM PUBLISHER]

The size-dependent elastic property of rectangular nanobeams (nanowires or nanoplates) induced by the surface elasticity effect is investigated by using a developed modified core-shell model. The effect of surface elasticity on the elastic modulus of nanobeams can be characterized by two surface related parameters, i.e., inhomogeneous degree constant and surface layer thickness. The analytical results show that the elastic modulus of the rectangular nanobeam exhibits a distinct size effect when its characteristic size reduces below 100 nm. It is also found that the theoretical results calculated by a modified core-shell model have more obvious advantages than those by other models (core-shell model and core-surface model) by comparing them with relevant experimental measurements and computational results, especially when the dimensions of nanostructures reduce to a few tens of nanometers. [ABSTRACT FROM AUTHOR]

A series of 1H-pyrano[2,3-d]pyrimidin-2(8aH)-one derivatives were synthesized via one-pot, three-component reaction of aromatic aldehydes, urea or thiourea, and 3,4-dihydro-2H-pyran using the green and inexpensive Brønsted acidic ionic liquid 1-methyl-2-pyrrolidinone hydrosulfate ([Hnmp]HSO4) as catalyst under solvent-free conditions. The method has several advantages such as mild conditions, shorter reaction time, good yields, and environmentally benign procedure. Moreover, the catalyst could be recovered conveniently and reused at least four times without evident loss of activity. [ABSTRACT FROM AUTHOR]

Purpose: In this study, the inhibitory activity of the methyl esters and derivatives extracted from Euphorbia kansui (Euphorbiaceae) and their effect on apoptosis and cell cycle distribution in the human gastric cancer cell line (SGC-7901) were evaluated., Methods: The inhibitory activity of the methyl esters and derivatives was evaluated by using trypan-blue, MTT (3-(4, 5-dimethyl thiazol-2yl) - 2, 5-diphenyltetrazolium bromide), and FCM (flow cytometry) assays. 5-fluorouracile (5-FU) was used for a positive control., Results: Six new methyl esters and derivatives were extracted from the root of E. kansui. Subjecting the SGC-7901 cell line to the extract indicated that methyl ester derivatives could initiate growth inhibition and induce apoptosis in these tumor cells. The inhibitory rates as measured from trypan-blue and MTT assays were significantly increased and are comparable to those of the common antitumor agent 5-FU. In addition, the methyl ester extract effectively inhibited the proliferation of SGC-7901 cells by interfering with the progression of the cells through the G1 phase of the cell cycle., Conclusion: The current study indicates that methyl esters might be a promising chemopreventive and chemotherapeutic agent for treating various forms of cancer by causing apoptosis and proliferation inhibition.