全文获取类型
收费全文 | 47篇 |
免费 | 7篇 |
专业分类
54篇 |
出版年
2023年 | 1篇 |
2021年 | 2篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 3篇 |
2002年 | 2篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1984年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有54条查询结果,搜索用时 15 毫秒
31.
The roots of Kniphofia foliosa afforded, in addition to chrysophanol, a novel anthraquinone named knipholone, whose structure was determined by spectroscopic methods as well as by degradation to known compounds 相似文献
32.
Aulinger K Arnold N Steglich W 《Zeitschrift für Naturforschung. C, Journal of biosciences》2000,55(5-6):481-484
From the acetone extract of the North American toadstool Lepiota americana 2-aminophenoxazin-3-one (1) and a novel amino-1,4-benzoquinone derivative, lepiotaquinone (2), were isolated. The structure of 2 was confirmed by its preparation from 2-aminophenol and amino-1,4-benzoquinone. 相似文献
33.
A new triterpene and its glycosides were isolated from the bark of Schefflera octophylla together with asiatic acid and asiaticoside. Based on spectroscopic data, especially 2DNMR, and chemical transformations the structures of the new compounds were determined as 3 alpha-hydroxy-urs-12-ene-23,28-dioic acid and 3 alpha-hydroxy-urs-12-ene-23,28-dioic acid 28-O-[alpha-L-rhamnopyranosyl (1----4)-O-beta-D-glucopyranosyl (1----6)]-beta-D-glucopyranoside. For the first time asiaticoside was isolated from a plant other than Centella asiatica. 相似文献
34.
U Herr W Spahl G Trojandt W Steglich F Thaler R van Eldik 《Bioorganic & medicinal chemistry》1999,7(5):699-707
Two new tripodal peptide ligands with histidine side chains have been synthesized and were shown to form stable zinc(II) complexes. Their NMR and mass spectra indicate a structure that is analogous to the active center of carbonic anhydrase. Both the ligands and the zinc complexes were titrated potentiometrically in order to obtain the pKa values for the coordinated water of the zinc complexes; due to the low solubility of the complexes only estimates could be obtained. 相似文献
35.
36.
37.
38.
39.
Wille G Mayser P Thoma W Monsees T Baumgart A Schmitz HJ Schrenk D Polborn K Steglich W 《Bioorganic & medicinal chemistry》2001,9(4):955-960
The yeast Malassezia furfur converts tryptophan into several indole compounds. One of these, malassezin, was identified as 2-(1H-indol-3-ylmethyl)-1H-indole-3-carbaldehyde (1). It was synthesized from N-Boc-indole-3-carbaldehyde in five steps with 12% overall yield. The compound easily cyclizes to indolo[3,2-b]carbazole (7) which is known to interact with the arylhydrocarbon receptor (AHR). Similarly, malassezin was found to induce cytochrome P450 as an agonist of AHR (EC50 = 1.57 microM) in rat hepatocytes. 相似文献
40.
Prochlorococcus marinus strain CCMP 1375 is the sole prokaryote to possess phycoerythrin in addition to (divinyl-)chlorophyll a/b binding antenna complexes. Here we demonstrate, employing a spectrofluorimetric assay, that phycoerythrin serves a light-harvesting antenna function (transfers energy to chlorophylls). 相似文献