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61.
Novel methods of synthesis of spiro acyloxyphosphoranes are described emphasizing the significance of the first isolated instance of these new species. Then, the no-catalyst alternating copolymerizations of the combinations of cyclic phosphorus(III) compounds (serving as nucleophilic monomer, MN) with acrylic acid derivatives and with α-keto acids (electrophilic monomer, ME) are mentioned. These copolymerizations proceed without added initiator. Spiro oxyphosphoranes play an important role in the copolymerization scheme in the equilibrium with the +MN - ME ? zwitterion, the key intermediate of the copolymerization. Finally, new reactions of spiro acyloxyphosphoranes with nucleophiles, alcoholysis and aminolysis polymerizations are presented. 相似文献
62.
Noboru Oyama Takeo Ohsaka Fumihiro Yoshimura Masaya Mizunuma Shuichiro Yamaguchi Norihiko Ushizawa 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10-11):1463-1473
The electrode characteristics of ion-selective electrodes (ISEs) for K+, Na+, NH4 +, and Ca2+ based on bilayer film coatings, where the inner layer films are electroactive electropolymerized ones and the outer layer films are composed of conventional ion-sensitive materials, have been examined. These ISEs of the coated-wire electrode type have no conventional internal reference solution and reference electrode, but the inner films may be considered to function as the “internal standard solution.” The ion selectivity coefficients and the activity range showing Nernstian response were almost comparable to those of conventional liquid-membrane electrodes. The bilayer-coated ISEs showed insensitivity to O2 and CO2, long-term stability, and little drift. It was also found that the electrode performance is practically unchanged after sterilization in an autoclave. The results demonstrate that the bilayer-coated ISEs examined are promising for the determination of K+, Na+, NH4 +, or Ca2+ activity in biological and environmental systems. 相似文献
63.
64.
Naruyoshi Komiya Takeharu Kageyama Masaya Naito Takeshi Naota 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):503-505
rac‐Bis{μ‐trans‐2,2′‐[pentane‐1,5‐diylbis(azanediyl)]ditroponato}dipalladium(II), [Pd2(C19H20N2O2)2], has been synthesized and fully characterized using single‐crystal X‐ray diffraction, 1H NMR, FT–IR and mass spectroscopy. The trans coordination, vaulted structure and anti conformation have been unequivocally established from the X‐ray diffraction studies. This is the first example of a bis(aminotroponato)palladium complex. In the crystalline state, the molecule has twofold symmetry and each molecular unit undergoes intermolecular offset π‐stacking of the tropone rings to afford heterochiral interpenetrating dimers that are aligned in a lamellar manner with a herringbone packing motif. 相似文献
65.
We have recently found that the reaction of α-keto acids (1) with phosphorus (III) compounds (3) yielded cyclic acyloxyphosphoranes(C-AOPs, 4), a new class of pentacovalent phosphorus species having a P-OC(O) group.1, 2) The present paper deals with a new reaction of glyoxylic acid (2) with 3 to give C-AOPs (5) having no substituent at the C-3 position. 1 is an α-keto acid whereas 2 can be taken as an α-formyl acid. Although it is well known in the field of organic chemistry that the formyl group often behaves differently from a keto group, the reaction of 2 with 3 provides an example in which both groups behave in a similar manner. 相似文献
66.
Yasushi Imada Takahiro Kitagawa Han-Kun Wang Naruyoshi Komiya Takeshi Naota 《Tetrahedron letters》2013,54(7):621-624
An aerobic, organocatalytic, and aqueous method for the oxidation of sulfides is described. Synthetic flavin, 5-ethyl-3,7,8,10-tetramethylisoalloxazinium perchlorate, acts as an efficient catalyst for the oxidation of sulfides in water under an oxygen atmosphere (1 atm) with the assistance of ascorbic acid as a reductant. This is an inexpensive, convenient, and environmentally benign method for the selective oxidative transformation of sulfides into sulfoxides. 相似文献
67.
Kenichi Takeo Kimiko Nagayoshi Kenichi Nishimura Shinichi Kitamura 《Journal of carbohydrate chemistry》2013,32(8):1159-1177
Abstract The 8-methoxycarbonyloctyl β-glycosides of the trisaccharides O-β-d-Glcp-(1 → 6)- O-β-d-Glcp-(1 → 3)-d-Glcp and O-β-d-Glcp-(1 → 3)-O-[β-d -Glcp-(1 → 6)]-d-Glcp and of the tetrasaccharide O-β-d-Glcp-(1 → 3)-O-[β-d-Glcp-(1 → 6)]-O-β-d-Glcp-(1 → 3)-d-Glcp, corresponding to the fragments of schizophyllan, have been synthesized by using mono- to tetrasaccharide 1-thioglycosides as glycosyl donors, each bearing a participating benzoyl group in the 2-position, and N-iodosuccinimide and silver triflate as promoter. Saponification of the tri- and tetrasaccharide β-glycosides, followed by attachment to bovine serum albumin of the resulting sugar derivatives having a carboxyl group at the aglycon terminal, provided neoglycoproteins for immunological studies of the polysaccharide. 相似文献
68.
The catalytic activities of the cationic synthetic flavin adduct 1 with various dendritic and non-dendritic 2,6-bis(acylamino)pyridines 2 were examined for the oxidation of organic sulfides with H2O2. The adduct of 5-ethyllumiflavinium perchlorate 1a with 2b–d bearing poly(benzyl ether) dendron units acts as an efficient organocatalyst for the oxidative transformation of sulfides to the corresponding sulfoxides under mild conditions. 相似文献
69.
Jun Yamamoto Nami Maeda Chiaki Komiya Tomohiro Tanaka Masaya Denda Koji Ebisuno Wataru Nomura Hirokazu Tamamura Youichi Sato Aiko Yamauchi Akira Shigenaga Akira Otaka 《Tetrahedron》2014
A fluoride-responsive (FR) amino acid that induces amide bond cleavage upon the addition of a fluoride was developed, and it was applied to an FR traceable linker. By the use of an alkyne-containing peptide as a model of an alkynylated target protein of a bioactive compound, introduction of the FR traceable linker onto the peptide was achieved. Subsequent fluoride-induced cleavage of the linker followed by labeling of the released peptide derivative was also conducted to examine the potential applicability of the FR traceable linker to the enrichment and labeling of alkynylated target molecules. 相似文献
70.
Miyauchi Suguru Yamada Shuji Takeuchi Shintaro Tazaki Asahi Kajishima Takeo 《Transport in Porous Media》2022,141(1):185-199
Transport in Porous Media - A concise and accurate prediction method is required for membrane permeability in chemical engineering and biological fields. As a preliminary study on this topic, we... 相似文献