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821.
AbstractVarious spirooxindoles (7a–c, 8a–c, 9a–c, and 10a–c) were efficiently synthesized using deep eutectic solvent ZnCl2+urea and well characterized using IR, 1H NMR, and 13C NMR spectroscopic techniques. The biological screening results showed that the compound 9a exhibited potent anticancer activity against MCF7 and HeLa cell lines with IC50 values 6.47?±?0.01 and 9.14?±?0.32?µM, respectively. The compound 7c exhibited potent activity against the HeLa cell line with IC50 value 6.81?±?0.01?µM. The compound 9a exhibited a potent antioxidant activity with IC50 value 7.34?±?0.17?µM. The comparative molecular docking study against the cancer proteins EGFR and HER2 revealed that the EGFR was the best target protein receptor for the target compounds. Among all the compounds, the compound 9a exhibited the least binding energy ?10.72?kcal/mol against the protein EGFR (PDB ID: 4HJO). 相似文献
822.
The reactivity of gem-ester group in cyclohexanone-1,1-dicatboxylates (1) was studied by reaction with Cu/quinoline and eerie ammonium nitrate. The resultant cyclohexanone-1-carboxylic acids (2) and cyclohexan-1,4-diones (3) were made use to develop selena/thiadiazole rings by exploiting α-ketomethylene group (6-9). Attempts to prepare cyclohexanones met without success. All the new compounds were characterized by elemental analyses and IR and 1H NMR spectral data 相似文献
823.
Vajrala Venkata Reddy Mandava Venkata Naga Brahmeswara Rao Ghanta Mahesh Reddy Khagga Mukkanti 《合成通讯》2013,43(23):3513-3523
Abstract Vardenafil hydrochloride trihydrate (Levitra) is used to treat erectile dysfunction (ED) and is an inhibitor of phosphodiesterase type 5 (PDE-5) enzyme. It maintains higher levels of cyclic guanosine monophosphate (cGMP), relaxes smooth muscles, promotes penile blood flow, and enhances erectile function. During the bulk drug synthesis of vardenafil hydrochloride trihydrate, six related substances (impurities), vardenafil dimer, vardenafil N-oxide, vardenafil glycene, vardenafil oxopiperazine, vardenafil oxoacetic acid, and phenyl vardenafil were identified, and these are reported herein for the first time. The present work describes the synthesis and characterization of these impurities. 相似文献
824.
An efficient, convenient, and novel one-pot method of 2,4,5-triaryl-1H-imidazoles synthesis using benzil, arene carbaldehydes, and ammonium acetate, catalyzed by uranyl nitrate hexahydrate [UO2(NO3)2·6H2O] supported on acidic alumina and resulting in good to excellent yields under heterogeneous conditions, is reported. Formation
of a reactants-catalyst complex was confirmed by UV-VIS spectral data. Antibacterial (MIC) and antioxidant activity of the
synthesized compounds was also studied. 相似文献
825.
The synthesis of 4 and 8 is reported. These intermediates are obtained by a one-pot tandem cyclization of 1 and 6, respectively, via Bischler Napieralski reaction followed by cyclopropylimine rearrangement. Compounds 4 and 8 were reduced by sodium borohydride in methanol to afford cytotoxic alkaloid (±)-crispine A and antileishmania compound (±)-harmicine. 相似文献
826.
Mangesh P. DushingC.V. Ramana 《Tetrahedron letters》2011,52(36):4627-4630
We report a simple strategy for the synthesis of a collection of C(3′)-spirodihydroisobenzo-furannulated nucleosides featuring a [2+2+2]-cyclotrimerization as the key reaction. The cyclotrimerization reactions are facile with the unprotected nucleosides having a diyne unit. When both alkynes of the diyne are terminal, the regioselectivity is poor. However, when one of the terminal alkynes is additionally substituted, the cyclotrimerizations are highly diastereoselective. Since the key bicycloannulation is the final step, this strategy provides flexibility in terms of the alkynes and is thus amenable for the synthesis of a focussed small molecule library. 相似文献
827.
Velvadapu V Paul T Wagh B Glassford I DeBrosse C Andrade RB 《The Journal of organic chemistry》2011,76(18):7516-7527
Novel sources of antibiotics are required to address the serious problem of antibiotic resistance. Telithromycin (2) is a third-generation macrolide antibiotic prepared from erythromycin (1) and used clinically since 2004. Herein we report the details of our efforts that ultimately led to the total synthesis of (-)-4,8,10-tridesmethyl telithromycin (3) wherein methyl groups have been replaced with hydrogens. The synthesis of desmethyl macrolides has emerged as a novel strategy for preparing bioactive antibiotics. 相似文献
828.
829.
830.
Karthikraja Esackraj Dr. Naga Venkateswara Rao Nulakani Dr. Venkata Surya Kumar Choutipalli Dr. Chandra Chowdhury Dr. Palanichamy Murugan Dr. V. G. Vaidyanathan Prof. Venkatesan Subramanian 《Chemphyschem》2023,24(11):e202300035
Generally, graphynes have been generated by the insertion of acetylenic content (−C≡C−) in the graphene network in different ratios. Also, several aesthetically pleasing architectures of two-dimensional (2D) flatlands have been reported with the incorporation of acetylenic linkers between the heteroatomic constituents. Prompted by the experimental realization of boron phosphide, which has provided new insights on the boron-pnictogen family, we have modelled novel forms of acetylene-mediated borophosphene nanosheets by joining the orthorhombic borophosphene stripes with different widths and with different atomic constituents using acetylenic linkers. Structural stabilities and properties of these novel forms have been assessed using first-principles calculations. Investigation of electronic band structure elucidates that all the novel forms show the linear band crossing closer to the Fermi level at Dirac point with distorted Dirac cones. The linearity in the hole and electronic bands impose the high Fermi velocity to the charge carriers close to that of graphene. Finally, we have also unravelled the propitious features of acetylene-mediated borophosphene nanosheets as anodes in Li-ion batteries. 相似文献