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1.
AbstractFour new compounds, compounds 1, 2, 4, 6, along with two known compounds 3, 5, were isolated from the methanol extract of the fruiting body of Neoboletus magnificus. The structures of compounds were elucidated by HRMS and NMR spectroscopic methods. The in vitro anti-inflammatory activity of the isolated compounds was evaluated. 相似文献
2.
AbstractA new C19-diterpenoid alkaloid named hemsleyaline (1), along with fourteen known alkaloids (2-15), were isolated from the roots of Aconitum hemsleyanum Pritz. (Ranunculaceae), a herbal medicine in southwest China. Their structures were established on the basis of extensive spectroscopic analyses. Compound 1 showed mild cholinesterase inhibitory effect with IC50 value of 471?±?9?μM. 相似文献
3.
In the course of our investigation on Aconitum and Delphinium species, we have isolated a number of norditerpenoid and diterpenoid alkaloids from A. kuzsnezoffii and A. hemsleyanum var. pengzhouense1~6. We have found that a norditerpenoid alkaloid, 6-epiforsticine isolated from both plants shows a great deal of similarity to forsticine7 but significantly differed from the latter in its 13C NMR spectrum (Table l), suggesting that the alkaloids were a pair of epimers at C-6. The present comm… 相似文献
4.
In recent years, an increased interest in the phytochemistry of the Annonaceae has beensparked by the isolation of the antileukemic Annonaceous acetogenin'. Saccopela/umprolificllm (Chun el How) Tsiang (Allnonaceae) is an evergreen tree distributed inHainan Province, P. R. China. The ethanolic extract of the plant exhibited cell growthinhibitory activity (20 ig/ml) against LIZ10 lymphocytic leukemia. A new alkaloid,prolifine (l), was isolated from the roots of S. proldicum, in addition t… 相似文献
5.
Inourpreviouspapers1-3,wehavereportedtheisolationandelucidationofaseriesofnewditerpenoidalkaloidsfromtheaerialpartofDelphiniumsoulieiFranch.Inthisstudy,phytochemcalinvestigationsontheconstituentsoftherootsofthisplanthaveledtotheisolationofaminornewditerpenoidalkaloidsoulidine.A Minor New Diterpenoid Alkaloids from the Roots of Delphinium Souliei Franch1. K. Zhang, L. He, X. Pan, YZ. Chen Planta Med, 1998, 64(6), 580.
2. L. He, Y J. Pan, X. Pan, B. G. Li, Y Z. Chen Chin. Chem.… 相似文献
6.
The paper reports the formation and crystal structure of dihydronitidine, expounds thereasons and conditions of easily formed oxynitidine, and discusses anticancer mechanism ofnitidine (cation). The crystallographic parameters of dihydronitidine are: space group P2_(1/n),a= 12.54(1), b = 9. 148(5), c = 14.748(8)A, β= 92. 12(6)°,Z =4. 4108 independent reflec-tions were collected within the range of 3°≤2θ≤54°, of which 2137 intensity data with I≥3σ(I) were used in the structural determination. The crystal structure has been refined byfull matrix least-square method to a final R of 0.050. 相似文献
7.
在通过Diels-Alder反应建立各种含氮六员环的反应中,亚胺是一个最有用的亲双烯试剂。该法应用简便、并显示出较好的位置选择性和立体选择性。对其在生物碱类合成中的应用也作了综述。 相似文献
8.
An investigation of the alkaloidal constituents of the leaves of Catharanthus roseus has led to the isolation of a new alkaloid, “rosicine”, to which structure (1) has been assigned on the basis of spectroscopic studies. Two other alkaloids isolated have been identified as 14, 15-dehydroepivincadine and 19-hydroxytabersonine. 相似文献
9.
Yong-Li Li Qiang Zhang Jian-Jun Wu Li-Jun Xue Li-Ming Chen Jun-Mian Tian Zhuo-Ni Xu Ying Chen Xian-Wen Yang Xiao-Jiang Hao Jie Li 《Tetrahedron letters》2019,60(10):751-753
From Abies nukiangensis, two novel 13,14-seco-abietane diterpenes, nukiangendines A (1) and B (2) were isolated. Their relative structures were determined by extensive NMR and HRMS spectroscopic analysis. The absolute configuration of 1 was established by ECD calculations. Compound 1 showed significant anti-hepatitis C virus (HCV) effects. 相似文献
10.
Sanjib Gogoi 《Tetrahedron letters》2009,50(19):2252-1652
The first enantioselective synthesis of biologically active 6-amino-5-cyanodihydropyrano[2,3-c]pyrazoles has been achieved through a cinchona alkaloid-catalyzed tandem Michael addition and Thorpe-Ziegler type reaction between 2-pyrazolin-5-ones and benzylidenemalononitriles. The reaction may also be carried out in a three-component or a four-component fashion via the in situ formation of these two components from simple and readily available starting materials. The desired products were obtained in excellent yields with mediocre to excellent enantioselectivities (up to >99% ee). 相似文献