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排序方式: 共有206条查询结果,搜索用时 125 毫秒
121.
Maxim Oshchepkov Leonid Kovalenko Antonida Kalistratova Maria Ivanova Galina Sherstyanykh Polina Dudina Alexey Antonov Anastasia Cherkasova Mikhail Akimov 《Molecules (Basel, Switzerland)》2022,27(11)
Natural cytokinines are a promising group of cytoprotective and anti-tumor agents. In this research, we synthesized a set of aryl carbamate, pyridyl urea, and aryl urea cytokinine analogs with alkyl and chlorine substitutions and tested their antiproliferative activity in MDA-MB-231, A-375, and U-87 MG cell lines, and cytoprotective properties in H2O2 and CoCl2 models. Aryl carbamates with the oxamate moiety were selectively anti-proliferative for the cancer cell lines tested, while the aryl ureas were inactive. In the cytoprotection studies, the same aryl carbamates were able to counteract the CoCl2 cytotoxicity by 3–8%. The possible molecular targets of the aryl carbamates during the anti-proliferative action were the adenosine A2 receptor and CDK2. The obtained results are promising for the development of novel anti-cancer therapeutics. 相似文献
122.
A visible-light-induced external catalyst-free decarboxylation of dioxazolones was realized for the bond formation of N=P and N–C bonds to access phosphinimidic amides and ureas. Various phosphinimidic amides and ureas (47 examples) were synthesized with high yields (up to 98%) by this practical strategy in the presence of the system’s ppm Fe. 相似文献
123.
《Mendeleev Communications》2020,30(2):153-155
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124.
Carbonylation of functionalized diamine diols to cyclic ureas: application to derivatives of DMP 450
Synthesis of the cyclic urea core structure of the HIV protease inhibitor DMP 450 has been achieved via W(CO)6/I2-catalyzed carbonylation of diamine intermediates. Carbonylations of related functionalized diamines to derivatives of the DMP 450 core structure were also examined. Selected diamine diol substrates could be converted to the cyclic urea core structure by catalytic carbonylation without protection of the diol functionality. 相似文献
125.
A convergent, organocatalytic visible-light-mediated process for the synthesis of diaryl sulfides has been developed. A broad range of aryl thiols reacted with various aryl diazonium salts in the presence of eosin Y under air atmosphere to afford the desired diaryl sulfides in high yields. This novel and environmentally friendly method provides an alternative route to established synthetic approaches. 相似文献
126.
Fehmi Damkaci Cihad Sigindere Thomas Sobiech Erik Vik Joshua Malone 《Tetrahedron letters》2017,58(36):3559-3564
Copper-catalyzed modified Ullmann coupling reactions creating C–O bonds, including diaryl ethers or phenols, are vital to organic synthesis. Synthesized N-phenyl-2-pyridinecarboxamide and its derivatives were used as ligands in conjunction with catalytic copper sources in the formation of various diaryl ethers and phenols. Various aryl and heteroaryl halides with electron donating and withdrawing groups were reacted with various phenols under mild reaction conditions providing moderate to excellent yields. 相似文献
127.
Liza Shrestha Hardik J. Patel Yanlong Kang Sahil Sharma Gabriela Chiosis Tony Taldone 《Tetrahedron letters》2017,58(48):4525-4531
A copper-mediated synthesis of diaryl sulfides utilizing Cu(I)-thiophene-2-carboxylate (CuTC) is described. We demonstrate the use of CuTC as a soluble, non-basic catalyst in the coupling of aryl iodides and aryl thiols in the synthesis of synthetically advanced diaryl sulfides. This method allows for the successful coupling of challenging substrates including ortho-substituted and heteroaryl iodides and thiols. Additionally, most of the aryl iodide substrates used here contain the privileged piperazine scaffold bound to a pyrimidine, pyridine, or phenyl ring and thus this method allows for the elaboration of complex piperazine scaffolds into molecules of biological interest. The method described here enables the incorporation of late-stage structural diversity into diaryl sulfides containing the piperazine ring, thus enhancing the number and nature of derivatives available for SAR investigation. 相似文献
128.
The excellent catalytic potential of sulfated polyborate is utilized in the synthesis of (un)symmetrical ureas and benzimidazolones by heating amines or substituted OPDA and urea or N-phenylureas under a solvent-free condition at 120?°C is described. The key advantages of the present protocol are phosgene-free, and other hazardous reagents or organic solvent free, high reaction rates and yields, simple workup procedure, and recyclability of the catalyst. 相似文献
129.
Wen‐Jie Tang 《合成通讯》2013,43(17):2461-2468
A general and efficient method for the preparation of 2,4‐diaryl‐1,2,3‐triazoles from α‐hydroxyacetophenones and phenylhydrazines is reported. The essential characteristics of this method include mild reaction conditions, a straightforward workup procedure, and comparatively higher yields. 相似文献
130.
A new series of 1-alkyl-2-oxo-1,2-dihydro-pyrimidine-5-carboxalic acid amides is described. The reaction of N-((E)-3-(dimethylamino)-2-formylacryloyl) formamidine, an intermediate obtained by Vilsmeier–Haack formylation of acetonitrile with various mono-substituted ureas, provides such compounds in good yields. 相似文献