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61.
E. V. Tret'yakova O. B. Flekhter F. Z. Galin L. V. Spirikhin G. A. Tolstikov 《Chemistry of Natural Compounds》2002,38(3):246-248
Diterpene indoles were prepared by the Fischer reaction from cyclopentenonepimaric acid. The structures of the synthesized compounds were confirmed by IR and NMR spectroscopies. 相似文献
62.
以间异丙基溴苯1为起始原料,通过进攻环氧乙烷及溴代两步制得溴化物3.溴化物3与Hagemann′s酯发生偶联反应,水解后生成偶联产物5.再以路易斯酸BF3·Et2O催化化合物5进行分子内环化为关键步骤得到反式稠合中间体6,最后通过与三苯基膦碘甲烷季盐发生Wittig反应及氧化,合成了(±)-19-去甲基-4(18),8,11,13-四烯-松香烷-7-酮[19-nor-abieta-4(18),8,11,13-tetraen-7-one](8). 相似文献
63.
64.
S. A. Osadchii E. E. Shul’ts E. V. Polukhina M. M. Shakirov G. A. Tolstikov 《Russian Chemical Bulletin》2006,55(6):1077-1084
Lappaconitine and N-deacetyllappaconitine derivatives containing bromine and iodine atoms in the aromatic moiety were synthesized. The Heck cross-coupling
of these halides with ethyl acrylate or 2-methyl-5-vinylpyridine afforded new olefinated lappaconitine derivatives.
Dedicated to the memory of Academician V. A. Koptyug on the occasion of the 75th anniversary of his birth.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1038–1044, June, 2006. 相似文献
65.
Bagryanskaya I. Yu. Gatilov Yu. V. Ganbaatar J. Osadchii S. A. Shakirov M. M. Shults E. E. Tolstikov G. A. 《Russian Chemical Bulletin》2001,50(11):2092-2094
Oximation of songorine afforded a mixture of its Z- and E-oximes. The crystal and molecular structure of the Z-isomer was established by X-ray diffraction analysis. Its structure was also confirmed by the spectral data (2D 1H—1H and 13C—1H NMR spectroscopy and mass spectrometry). The structure of isomeric E-oxime was established by comparing its NMR spectroscopic data (1H and 13C) with the data for the Z-isomer. 相似文献
66.
Yangqing He Shanshan Jin Zhanying Ma Jie Zhao Qian Yang Qian Zhang 《Natural product research》2020,34(6):872-875
AbstractRaspberry, the fruit of Rubus Chingji Hu, is a widely distributed economic staple food in China. It has long been used as a traditional medicine in mainland China to treat kidney enuresis, nocturnal emission and premature ejaculation in clinic. In this paper, six known compounds (1?–?6) were purified from the fruits of Rubus chingji. Their structures were elucidated as (16α)-16,17-dihydroxy-ent-kauran-2-one17-O-β-D-glucopyranoside (1), (16R) -16,17-dihydroxy-ent-kaurane-2-one (2), 3,3′-di-O-methylellagic acid 4-(5′′-acetyl)-α-L-arabinofuranoside (3), quercilicoside A (4), esculetine (5) and ethyl-β-D-glucoside (6). All the compounds were isolated from Rubus Chingji Hu for the first time. Compounds 3 and 5 shown distinctive free radical scavenging activities in DPPH and FRAP assays. In addition, no cytotoxicity was observed for compounds 3 and 5 against different cancer cells, suggesting that they might be useful as potential antioxidant agents against various reactive oxygen species. 相似文献
67.
A minor, unprecedented diterpene, 3β,17‐dihydroxycleistantha‐12,15‐dien‐2‐one ( 1 ), was isolated from the CHCl3‐soluble part of the EtOH extract of the pericarp of Trewia nudiflora. The structure of 1 was elucidated by means of 1D‐ and 2D‐NMR spectroscopic analyses as well as by HR‐MS. Also isolated were two known triterpenes, glutin‐5‐en‐3‐ol and olean‐18‐en‐3‐one (germanicone), as well as three known sterols, (22E,24R)‐5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, (22E,24R)‐5α,8α‐epidioxyergosta‐6,9(11),22‐trien‐3β‐ol, and (22E,24R)‐6‐methoxyergosta‐7,22‐dien‐3,5‐diol. 相似文献
68.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(5):635-640
We report the isolation of a novel diterpene, designated as `amethane', from Isodon amethystoides (Lamiaceae). The diterpene [amethinol A; systematic name: (4aR,4bR,7R,10aS)‐4b,7‐dihydroxy‐7‐isopropyl‐1,1‐dimethyl‐9‐oxododecahydrobenzo[a]azulene‐4a(2H)‐carboxylic acid], possesses a unique skeleton containing a six/five/seven‐membered tricyclic system. Intermolecular O—H…O close contacts were found to the carboxyl, carbonyl and hydroxy groups, connecting molecules into a two‐dimensional structure. A possible biosynthetic pathway has been proposed. In addition, the compound was evaluated for its biological activities against different disease targets, and was found to significantly attenuate RORγt‐dependent autoimmune responses. 相似文献
69.
《Journal of separation science》2018,41(18):3515-3526
Benzoyl aconite alkaloids have myocardial protective effects at a low dose and produce toxic effects at high dose. Due to lack of enough reference compounds, most of the benzoyl alkaloids had few concerns, except the typical ones, i.e. aconitine, mesaconitine, and hypaconitine. To rapidly screen out and quantify benzoyl alkaloids, a high performance liquid chromatography combined with tandem mass spectrometry was proposed based on precursor ion scanning mode. First, a diagnostic ion at m/z 105 corresponding to benzoyl group was observed by using tandem mass spectrometry, which could be used for the rapid identification of benzoyl alkaloids. The targeted screening of these alkaloids was then conducted by using precursor ion scan of characteristic ion at m/z 105. Shengfuzi (the lateral root of A. carmichaelii) was taken as example, and 24 benzoyl‐containing alkaloids were identified. The six major alkaloids including aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine were determined in the precursor ion scan mode by the standard curve method. Reliable linearity, sensitivity, precision, accuracy, and repeatability were obtained and validated. Then the relative response factors between these six analytes were calculated, which were not more than two times using any alkaloid as reference. Thus, the other 18 alkaloids lacking reference compounds were relatively quantified. This approach provides a useful tool for rapid identification and quantitative analysis of toxic benzoyl alkaloids, and also an efficient method for the safety assessment of Aconitum roots. 相似文献