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71.
Ren‐Qiang Mei Qing Lu Yan‐Fen Hu Hai‐Yang Liu Fu‐Kai Bao Yu Zhang Yong‐Xian Cheng 《Helvetica chimica acta》2008,91(1):90-96
Three new linear C14 polyyne (=polyacetylene) glucosides, cordifolioidynes A–C ( 1 – 3 ), together with two known polyynes, lobetyol ( 4 ) and lobetyolin ( 5 ), and five known phenylpropanoids, i.e., sinapinaldehyde ( 6 ), coniferaldehyde ( 7 ), coniferoside ( 8 ), sachaliside ( 9 ), and isoconiferin ( 10 ), were isolated from the roots of Codonopsis cordifolioidea. The structures of 1 – 3 were established from spectral evidences and by characterization of their hydrolysis products. Acid hydrolysis of 1 afforded the aglycone 1a , while hydrolysis of 2 and 3 gave the cyclization products 2a and 3a , respectively. Compounds 4 – 10 were isolated from this plant for the first time. The antibacterial activity of compounds 1 – 5 were assessed against eight microbial strains by the agar dilution method, none of them exhibited antibacterial effects at concentrations up to 100 μg/ml. 相似文献
72.
A novel diterpenoid, multidione, has been isolated from the stems of Jatropha multifida and its structure has been settled from 1D and 2D NMR spectra. The compound possesses a phenolic moiety and a long side chain, structurally similar to the B ring of other lathyrane-diterpenoids in seco-form.The compound has possibly been derived biogenetically from a related lathyrane-diterpenoid. 相似文献
73.
Further phytochemical investigation of the roots of Aconitum hemsleyanum var. circinatum resulted in the isolation of three new aconitine‐type C19‐diterpenoid alkaloids, hemsleyanines E–G ( 1 – 3 , resp.). The structures of these new alkaloids were elucidated on the basis of spectral data including 2D‐NMR. 相似文献
74.
Guangyin Wang Junzeng Zhang Marianna Kulka Fujiang Guo Yiming Li 《Helvetica chimica acta》2014,97(7):985-991
Three new eremophilane glucosides, namely, petasitosides A–C, and seven known eremophilane‐type sesquiterpenoids were isolated from the roots of Petasites japonicus. Their structures were elucidated by spectroscopic techniques including 1D‐ and 2D‐NMR spectroscopy and mass spectrometry. This is the first report on eremophilane glycosides from the genus Petasites. 相似文献
75.
Using ozonolysis of the acid-catalyzed cyclized products of (−)-nidorellol and air-autoxidation as the key steps, (+)-ambrox was obtained in 53% overall yield. In the course of our synthesis, we discovered that (−)-nidorellol provided (+)-ambrox instead of the expected product, (−)-ambrox. Thus the absolute configuration of (−)-nidorellol was proved to be trans-(5R∗,7R∗,8R∗,9S∗,10R∗)-labda-12,14-diene-7α,8β-diol, which is opposite to that illustrated in a previous report. 相似文献
76.
77.
An efficient 12-step route for the synthesis of the diterpenoid quinone (±)-danshexinkun A in 23% overall yield from the corresponding highly substituted stilbene using a photocyclization strategy is described. 相似文献
78.
Castanolide (1) and epi-castanolide (2), two novel diterpenoids possessing a unique seco-norabietane skeleton, were isolated from Salviacastanea Diels f. pubescens Stib. Their structures and relative stereochemistry were elucidated by extensive NMR analysis and confirmed by single-crystal X-ray diffraction study. A possible biosynthetic pathway of these two compounds was also proposed. 相似文献
79.
Shuai Wang Xiaopo Zhang Xin Li Qibing Liu Yue Zhou Peng Guo 《Natural product research》2019,33(6):893-896
The phenylpropanoid glucosides from Tadehagi triquetrum were found to be beneficial to glucose and lipid metabolism in vitro. Herein, we investigated the effects of these compounds on oxidised low-density lipoprotein (oxLDL)-induced foam cell formation in RAW264.7 macrophages, aiming to evaluate their potential utility in prevention of atherosclerosis. Our results showed that three out of seven phenylpropanoid glucosides significantly inhibited oxLDL-evoked foam cell formation. These three compounds remarkably inhibited cholesterol influx and enhanced cholesterol efflux. Treatment with compounds 3, 4 and 7 significantly down-regulated the expression of scavenge receptors 1 (SR-1) and cluster of differentiation 36 (CD36) and increased the expression ATP-binding cassette transporters A1 and G1 (ABCA1 and ABCG1). Analyses of structure–activity relationships revealed that cinnamyl group was the most pivotal group for their activities. This work provided phenomenon that these phenylpropanoid glucosides are effective regulator of cholesterol influx/efflux and may be useful in leading for development of anti-atherosclerotic agents. 相似文献
80.
N. F. Samoshina M. V. Denisenko V. A. Denisenko N. I. Uvarova 《Chemistry of Natural Compounds》2003,39(6):575-582
A preparative synthesis of glucosides of the lupane-type triterpene acids betulinic, dihydrobetulinic, betulonic, dihydrobetulonic, and 3,20-dioxo-30-norlupan-28-oic was proposed. Glycosylation of 3-hydroxyacids by -acetobromoglucose (ABG) with Ag2O was performed in pyridine (Py)to formglycosides at C-28, repeated glycosylation of which by these same reagents but in CH2Cl2 generated a glycoside bond at C-3 to form bisglucosides. 28-Glucosides of ketoacids were formed in high yields in both Py and CH2Cl2. 相似文献