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101.
A series of novel bispyrazoles joined by arylmethylene at C‐4 position were synthesized with aromatic aldehydes obtained from lignin and screened for their in vitro antioxidant activities by N,N‐diphenyl‐N′‐picrylhydrazyl (DPPH) and 2,2′‐azino‐bis(3‐ethylenzothiazoline‐sulphonic acid) diammonium salt (ABTS+) radical scavenging assays. All of these compounds exhibited good DPPH and ABST+ radical scavenging activities as compared to the standard, Trolox, which suggested their potential as promising agents for curing tumors or other free radical‐related diseases. 相似文献
102.
《Journal of Coordination Chemistry》2012,65(4):423-430
A new 1-D cadmium(II) mixed ligand dimer supramolecular ladder [Cd2 L 4(3,5-DNBA)2]H2O (1), (L?=?3-(2-pyridyl)pyrazole and 3,5-DNBA?=?3,5-dinitrobenzoate) was synthesized by hydrothermal methods. X-ray structural analysis of complex 1 revealed that two cadmium(II) cores are bridged by two deprotonated pyrazole groups of L, leading to dinuclear cadmium(II) [Cd2 L 4(3,5-DNBA)2]. The dimers are joined by hydrogen-bonding interactions between two different cadmium(II) dimers to form a one-dimensional ladder-like framework and stabilized by weak π–π interactions. Moreover, the fluorescence spectrum of compound 1 exhibits blue fluorescent emission in the solid state at room temperature. 相似文献
103.
104.
1 INTRODUCTIONInrecentyears ,triazolo[3,4, b] 1 ,3,4 thiadiazolederivativeshavebeenat tractingmuchattentionfromchemistsandpharmacologistsbecausetheyshowbroadspectraofbiologicalactivities,suchasinsecticidal[1 ] ,antifungal[2 ] ,herbicidal[3] ,an tibacterial[4] ,hypotensiv… 相似文献
105.
Yassine Kaddouri Redouane Benabbes Sabir Ouahhoud Magda Abdellattif Belkheir Hammouti Rachid Touzani 《Molecules (Basel, Switzerland)》2022,27(9)
Bayoud disease affects date palms in North Africa and the Middle East, and many researchers have used various methods to fight it. One of those methods is the chemical use of synthetic compounds, which raises questions centred around the compounds and common features used to prepare targeted molecules. In this review, 100 compounds of tested small molecules, collected from 2002 to 2022 in Web of Sciences, were divided into ten different classes against the main cause of Bayoud disease pathogen Fusarium oxysporum f. sp. albedinis (F.o.a.) with structure–activity relationship (SAR) interpretations for pharmacophore site predictions as (δ−···δ−), where 12 compounds are the most efficient (one compound from each group). The compounds, i.e., (Z)-1-(1.5-Dimethyl-1H-pyrazole-3-yl)-3-hydroxy but-2-en-1-one 7, (Z)-3-(phenyl)-1-(1,5-dimethyl-1H-pyrazole-3-yl)-3-hydroxyprop-2-en-1-one 23, (Z)-1-(1,5-Dimethyl-1H-pyrazole-3-yl)-3-hydroxy-3-(pyridine-2-yl)prop-2-en-1-one 29, and 2,3-bis-[(2-hydroxy-2-phenyl)ethenyl]-6-nitro-quinoxaline 61, have antifungal pharmacophore sites (δ−···δ−) in common in N1---O4, whereas other compounds have only one δ− pharmacophore site pushed by the donor effect of the substituents on the phenyl rings. This specificity interferes in the biological activity against F.o.a. Further understanding of mechanistic drug–target interactions on this subject is currently underway. 相似文献
106.
The current work presents an objective overview of the impact of one important heterocyclic structure, the pyrazole ring, in the development of anti-proliferative drugs. A set of 1551 pyrazole derivatives were extracted from the National Cancer Institute (NCI) database, together with their growth inhibition effects (GI%) on the NCI’s panel of 60 cancer cell lines. The structures of these derivatives were analyzed based on the compounds’ averages of GI% values across NCI-60 cell lines and the averages of the values for the outlier cells. The distribution and the architecture of the Bemis–Murcko skeletons were analyzed, highlighting the impact of certain scaffold structures on the anti-proliferative effect’s potency and selectivity. The drug-likeness, chemical reactivity and promiscuity risks of the compounds were predicted using AMDETlab. The pyrazole ring proved to be a versatile scaffold for the design of anticancer drugs if properly substituted and if connected with other cyclic structures. The 1,3-diphenyl-pyrazole emerged as a useful scaffold for potent and targeted anticancer candidates. 相似文献
107.
Ibon Alkorta José Elguero H.V. Rasika Dias Devaborniny Parasar Manuel Martín-Pastor 《Magnetic resonance in chemistry : MRC》2020,58(4):319-328
This work reports the calculation of the nuclear magnetic resonance (NMR) chemical shifts of eight trinuclear Ag(I) complexes of pyrazolate ligands using the relativistic program ZORA. The data from the literature concern exclusively 1H, 13C, and 19F nuclei. For this reason, one of the complexes that is derived from 3,5-bis-trifluoromethyl-1H-pyrazole has been studied anew, and the 15N and 109Ag chemical shifts determined for the first time in solution. Solid-state NMR data of this compound have been obtained for some nuclei (1H, 13C, and 19F) but not for others (14N, 15N, and 109Ag). 相似文献
108.
COOEtCOCH3(CH3)2NNHNH2NNCH3OOEtNH2NH2NNCH3ONHNH2PhNCSNNCH3ONHNHCNHSOH-NNCH3NNHNPhS12345 1 INTRODUCTION A large number of 1,2,4-triazole derivatives have been synthesized in recent years[1~4]. Many of them are reported to exhibit broad spectrum biologi-… 相似文献
109.
合成了N-(邻氯苯基)氨基乙酸铜(Ⅱ)和N-(邻甲基苯基)氨基乙酸铜(Ⅱ)的单晶体,测定了它们的晶体结构,并对其电子结构进行EHMO计算。N-(邻氯苯基)氨基乙酸铜(Ⅱ)属单斜晶系,空间群P2,/a.a=8.786(4),b=7.777(2),c=11.956(2)A,β=96.01(3)°,V=812.4A,Z=2,Dc=1.77g·cm~-;N-(邻甲基苯基)氨基乙酸铜(Ⅱ)属单斜晶系,空间群P2,/a,a=8.925(6),b=7.973(8),c=11.856(9)Aβ=96.23(6),V=838.6A,Z=2,Dc=1.55g·cm~(-?)。两配合物互为异质同晶。配合物中,铜原子为分子的对称中心,并与两个配位体的两个羧基氧和两个氨基氮原子形成四方形配位结构,平均Cu-O键长为1.902A,Cu-N为2.050A。量子化学计算表明,在配位键的形成中,铜原子的d轨道的作用均不大,但配体中苯环上取代基的性质对Cu-N键强度有一定影响。 相似文献
110.