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1.
The reactivity of N1-alkylsulfonyl- and N1-arylsulfonyl-2′,3′,5′-tri-O-acetylinosine with benzylamine and with 15NH3, regarding the attack on C2, has been shown to be in the order CF3SO2 (Tf) > 2,4-(NO2)2C6H3SO2 (DNs) ? 4-NO2C6H4SO2 (pNs) ≈ C6F5SO2 (PFBs) > 2-NO2C6H4SO2 (Ns) ? CH3SO2 (Ms) > 4-CH3C6H4SO2 (Ts) > 2,4,6-(CH3)3C6H2SO2 (Mts). In spite of its intermediate reactivity, the Ns group is the most appropriate, since in this case the formation of by-products is minimised during the ring-opening and ring-closing steps of the process. Another advantage of the Ns group is thus disclosed. 相似文献
2.
Kh. Polvonov Q. Sabirov Kh. M. Shakhidoyatov 《Chemistry of Heterocyclic Compounds》2003,39(2):228-232
The reaction of 5-anilino(toluidino-, morpholino)-1,3,4-thiadiazoline-2-thiones at 80°C with allyl bromide and benzyl chloride in alcohol, acetonitrile or DMF in the presence of KOH and also with phenoxymethyloxirane in alcohol in the absence of base gives the corresponding novel allyl-, benzyl-, and 2-hydroxy-3-phenoxypropyl products substituted at the exocyclic S atom. Alkylation of the indicated thiones with benzyl chloride at 150-153°C in DMF in the presence of KOH occurs similarly. Under these conditions, allyl bromide forms alkylation products at the endocyclic N(3) atom as a result of an SN thio-Claisen rearrangement of the initially formed product which is allyl substituted at the exocyclic S atom. 相似文献
3.
Alkylation of 8-dimethylamino-1-methylamino-4-nitronaphthalene in the CD3I/KOH/DMSO system afforded a 4-nitro derivative containing the N(CD3)Me group in position 1. Direct proof of the structure of the intramolecular hydrogen bond in solutions of monoprotonated
4-R-1,8-bis(dimethylamino)naphthalenes was obtained for the first time. 1H NMR study revealed that the chelated NH proton is shifted to the N(8) atom for R = NO2 and NH3
+ and to the N(1) atom for R = NH2.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 159–162, January, 2006. 相似文献
4.
An efficient method for N-alkylation of diethyl acetamidomalonate (DEAM) is reported. C-Alkenylation was achieved by treating the N-alkenylated DEAM with various electrophiles in the presence of Cs2CO3. RCM reactions of C- and N-alkenylated products gave cyclic amino acid derivatives in good yields. 相似文献
5.
Zee-Cheng and coworkers first prepared effica-cious antitumor agent M itoxantrone by leuco-1,4,5,8-tetrahydroxyanthraquinone reacting with 2-(2-am in-oethylam ino)ethanol,and they proposed structure-ac-tivity relationship(SAR)of anthraquinones as antitu-m… 相似文献
6.
Az-Eddine El Mansouri 《合成通讯》2019,49(14):1802-1812
The syntheses of N-Alkylpyrimidine derivatives by reacting pyrimidin-2,4-diones with appropriate alkyl halide under microwave irradiation at 400?W were compared to the conventional synthesis route. These methodologies are regioselective and compatible with numerous substrates and furnish the corresponding N-alkylpyrimidines in good yields using a cheap catalyst HMDS/KI in MeCN. A comparison study between these two different modes of heating was investigated. 相似文献
7.
1-十二烷基氮杂环庚烷-2-酮的合成 总被引:5,自引:0,他引:5
己内酰胺与溴代十二烷在氢氧化钾的作用下,于甲苯中进行N-烷基化反应,合成了1-十二烷基氮杂环庚烷-2-酮,收率88%~92%。 相似文献
8.
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10.
L. A. Sviridova I. F. Leshcheva G. K. Vertelov 《Chemistry of Heterocyclic Compounds》2000,36(10):1154-1160
Reaction of 1-acetyl-2-phenyl-5-hydroxypyrazolidines with amino acid esters occurs to give the corresponding N-pyrazolidinyl amino acids under mild conditions. 相似文献