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71.
Hiroyuki Takemura Teruo Shinmyozu Hirokazu Miura Islam Ullah Khan Takahiko Inazu 《Journal of inclusion phenomena and macrocyclic chemistry》1994,19(1-4):193-206
Side arm modifications of hexahomotriazacalix[3]arene (1) were achieved by simple synthetic methods. Compound5 has picolyl side arms and liquid-liquid extraction experiments showed that the alkali cation affinity of5 is much stronger than that of1. A chiral group was also introduced into the azacalixarene structure. Calix[4]arene was converted into dihomoazacalix[4]arene (2) in 8% yield. Clathrate formation of2 with various solvents is described. MM3 calculations were carried out onp-substituted analogs of2. The self-filled structure, in which the benzyl side arm is placed in its cavity, is the most stable structure when thep-positions of the aromatic rings carry small substituents. Strong hydrogen bonds between nitrogen and phenolic hydroxyl groups in dihomoazacalix[4]arene (2) were observed at low temperatures. The1H-NMR signals of phenolic hydroxyl groups appeared as six singlets in the range of 9.817.1 ppm at –70°C.This paper is dedicated to the commemorative issue on the 50th anniversary of calixarenes. 相似文献
72.
Immobilization of sunflower trypsin inhibitor (SFTI-1) peptide onto a gold surface and analysis of its interaction with trypsin 总被引:1,自引:0,他引:1
Sunflower trypsin inhibitor (SFTI-1) derived peptide having one disulfide bond could be immobilized via a thiol-disulfide exchange reaction onto a gold surface on a quartz crystal microbalance (QCM) chip. This permitted quantitative analysis of the specific interaction with trypsin. 相似文献
73.
Oxidation of [2.2]- and [3.3]paracyclophanols with benzeneseleninic anhydride readily afforded the corresponding cyclophane-o-quinones which showed the intramolecular charge-transfer interactions. 相似文献
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Coupling of glycosylated Fmoc-Thr or Fmoc-Ser with N-terminal amino acids on a resin proceeded smoothly under microwave irradiation for 20 min with much higher efficiency (98% yield per coupling) than found in more general conditions. Compared with a conventional protocol, the present method greatly reduces the time required for solid-phase glycopeptide synthesis from 4 days to 7 h, as is the case with the synthesis of Muc-1-related 20-residue glycopeptide carrying five core-2 trisaccharide chains. [structure: see text] 相似文献
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2,4,6-triphenylphosphinine (TPP) underwent unprecedented cofacial oxidative coupling to form a novel C2-symmetric cage compound, having extremely long C-C bonds. 相似文献
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