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71.
Tanaka M Nakamura M Ikeda T Ikeda K Ando H Shibutani Y Yajima S Kimura K 《The Journal of organic chemistry》2001,66(21):7008-7012
Synthetic procedures for monoazathiacrown ethers were explored, and monoazatrithia-12-crown-4, monoazatetrathia-15-crown-5, and monoazapentathia-18-crown-6 were obtained in moderate yields by the reaction of bis(2-chloroethyl)amine with the appropriate dithiols in the presence of lithium hydroxide in THF. To evaluate metal-ion binding properties of the monoazathiacrown ethers by solvent extraction, lipophilic dodecyl and dodecanoyl groups were incorporated onto the monoazathiacrown ethers. The solvent extraction experiments suggested that monoazathiacrown ethers have Ag(+) and Hg(2+) selectivities and that the relative selectivity between Ag(+) and Hg(2+) depends on their nitrogen atom properties and numbers of sulfur atoms reflecting the respective affinities of nitrogen and sulfur atoms to Hg(2+) and Ag(+). An interesting ability to bind Mg(2+) was observed in the case of N-dodecyl monoazatrithia-12-crown-4. 相似文献
72.
73.
Dehydration of zinc biladienone was catalyzed by zinc acetate, while the reverse reaction was catalyzed by triethylamine. The transformation can be performed thermally without catalyst, and the ratio of the hydrated form to the dehydrated form depended on the solvents: the dehydrated form is favored in CHCl3 and CH2Cl2, while the hydrated form is favored in hexane, pyridine, and DMF. Kinetic studies on the thermal transformation of zinc biladienone from its hydrated blue form to the dehydrated yellow-brown form were performed in toluene and THF. The rate law was half order with respect to the zinc biladienone concentration in toluene, while first order in THF, leading to a slow transformation in concentrated solution in toluene. 相似文献
74.
Kinetics of chemiluminescence reactions of 2-methyl-6-phenylimidazo[1,2-a]pyrazin-3(7H)-one (1c, Cypridina luciferin analogue) and substituent effects of the 6-aryl group of derivatives 1 strongly suggest that the rate-determining step is a single electron transfer from an anion derived from 1 to a triplet molecular oxygen (O2) in the oxygenation process. 相似文献
75.
76.
Pyrene-azacrown ether hybrid: cation-π interaction 总被引:1,自引:0,他引:1
A pyrene-modified lariat ether was synthesized in order to observe the cation-π interaction in solution. 相似文献
77.
Hiroyuki Ohno Yoshitaka Ogata Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1986,24(11):2959-2969
Small unilamellar liposomes were prepared in an aqueous medium by the sonication of phospholipids containing diene or triene groups in their hydrocarbon acyl chains. These liposomes were polymerized by gamma-ray irradiation. Conversion of polymerization was successively followed by UV spectrometry. Diene-type lipid liposomes were revealed for which a gamma-ray dose of 0.8 Mrad was required for complete polymerization and which were polymerized more easily than triene-type lipid liposomes. Triene-type lipids required 2.3 Mrad gamma ray to polymerize them completely. Contrary to UV-irradiation polymerization, there was no concentration dependence on the polymerization. Structure of the polymerized liposomes were confirmed by electron microscopy as small unilamellar liposomes. Study on the leakage of fluorescein from inner aqueous phase of the polymerized liposomes revealed that polymerized triene-type liposomes were relatively more stable than the polymerized diene-type liposomes. 相似文献
78.
Hiroyuki Nakazumi Takashi Endo Hikaru Sonoda Teijiro Kitao 《Journal of heterocyclic chemistry》1985,22(3):821-824
3-Substituted 2-phenyl-4H-1-benzothiopyran-4-ones (thioflavones) were prepared to test antimicrobial activity. It was found that 3-(phenyl)thiochromone derivatives (isothioflavones) were prepared by the Meerwein reaction of thiochromone with p-nitrobenzenediazonium ion. 3-(Formyl)thioflavone exhibits weak antimicrobial activity against Trichophytons and Candida. 相似文献
79.
80.