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81.
A simple, inexpensive, and efficient method for the synthesis of benzamides via the reaction of benzyl alcohols and amine hydrochloride salts in the presence of NaI as a green catalyst is described. Various derivatives of benzamide were synthesized in moderate to good yields using this method. 相似文献
82.
I. V. Ukrainets N. L. Bereznyakova V. A. Parshikov 《Chemistry of Heterocyclic Compounds》2009,45(3):345-350
4-Methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid hetarylamides can be prepared by two fundamentally different routes
with allowance made for the thermal stability of the starting hetarylamines.
* For Communication 152 see [1].
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 426–432, March, 2009. 相似文献
83.
An efficient self-cleavable purification tag could be a powerful tool for purifying recombinant proteins and peptides without additional proteolytic processes using specific proteases. Thus, the intein-mediated self-cleavage tag was developed and has been commercially available as the IMPACT™ system. However, uncontrolled cleavages of the purification tag by the inteins in the IMPACT™ system have been reported, thereby reducing final yields. Therefore, controlling the protein-splicing activity of inteins has become critical. Here we utilized conditional protein splicing by salt conditions. We developed the inducible intein-mediated self-cleaving tag (IIST) system based on salt-inducible protein splicing of the MCM2 intein from the extremely halophilic archaeon, Halorhabdus utahensis and applied it to small peptides. Moreover, we described a method for the amidation using the same IIST system and demonstrated 15N-labeling of the C-terminal amide group of a single domain antibody (VHH). 相似文献
84.
85.
86.
A simple, practical, and highly efficient copper-catalyzed one-pot synthesis of imidazo/benzoimidazoquinazolinones has been developed. The procedure is based on a sequential copper-catalyzed Ullmann-type N-arylation and aerobic oxidative intramolecular C-H amidation. This method should provide a new and useful strategy for construction of N-heterocycles. 相似文献
87.
Xinbo WangDavid Zhigang Wang 《Tetrahedron》2011,67(19):3406-3411
We reported herein new reactivities and possible mechanistic implications of a simplest oxidant (NaH/air) uncovered on a broad range of useful transformations, including aerobic alcohol oxidations, allylic alcohol isomerizations and oxidations, cyclopropyl alcohol fragmentations, and direct aryl aldehyde oxidative amidations. These readily implementable transition-metal-free processes feature exceptional material accessibility, operational simplicity, and environmental compatibility, and add new dimensions to its synthetic utilities that are fairly robust yet had not previously been fully realized and systematically explored. 相似文献
88.
Daniel P. Uccello Shawn M. MillerNoah A. Dieterich Antonia F. StepanSeungWon Chung Kathleen A. FarleyBrian Samas Jinshan ChenJustin I. Montgomery 《Tetrahedron letters》2011,52(33):4247-4251
Multi-gram quantities of C-13 functionalized pleuromutilin intermediates were synthesized under mild conditions via C-H amidation chemistry. The initial work was performed using rhodium catalysis. However, the highest yields were achieved using silver catalysis, resulting in stereoselective oxazolidinone formation. The ring closure was performed in the presence of a C-12 vinyl group, which differentiates it from historical methods involving the saturated pleuromutilin skeleton. A highlight of this vinyl template is a unique tetracyclic rearrangement product that can be generated from its treatment with hydrochloric acid and heat. 相似文献
89.
本文以异烟酸为原料,经酯化、酰胺化及霍夫曼降解,合成4-氨基吡啶.结果表明:选择的工艺路线合理,产品总收率可达50%左右. 相似文献
90.
I. V. Ukrainets L. V. Sidorenko O. S. Golovchenko 《Chemistry of Heterocyclic Compounds》2007,43(11):1434-1439
1-R-4-Hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids 2-nitrobenzylidenehydrazides are reduced to the corresponding
quinoline-3-carboxamides by zinc in glacial acetic acid but in refluxing triethylphosphite they are converted to the symmetrical
N,N′-di(4-hydroxy-2-oxo-1,2-dihydro-3-quinolinoyl)hydrazines. A study of the antitubercular activity of the synthetic compounds
has been carried out.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1687–1692, November, 2007. 相似文献