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961.
962.
The stereoregularity of polymethylthiiranes initiated by zinc and cadmium thiolates depends upon the nature of the metal, temperature, solvent and the monomer/initiator concentrations ratio. Complexation of the metal with monomer has been studied by (13C) and (1H) NMR on a model molecule, dimethylcadmium. Cryoscopic measurements made on a soluble cadmium thiolate have shown the presence of aggregates. The relationship between these observations and polymer stereoregularity is discussed. 相似文献
963.
964.
965.
G. T. Pilyugin Ya. O. Gorichok B. M. Gutsulyak S. I. Gorichok 《Chemistry of Heterocyclic Compounds》1966,1(6):603-608
Reaction of phenyl-ß-naphthylamines with formaldehyde and acetone in the presence of HCl and nitrobenzene in butanol solution leads to cyclization involving the naphthalene and phenyl rings, and formation of N-aryllepidine salts. 15 lepidine and 5, 6-benzoepidine salts are synthesized and characterized by their UV absorption spectra, as well as by their picrates.For Part LIII see [3]. 相似文献
966.
A H van Gennip J Grift E J van Bree-Blom D Ketting S K Wadman 《Journal of chromatography. A》1979,163(4):351-362
Chromatographic characteristics of urinary metabolites of theophylline were studied by two-dimensional thin-layer chromatography, high-performance liquid chromatography and gas chromatography--mass spectrometry. Quantitative date for the urinary metabolites of theophylline in asthmatic children are given. It was shown that 1,3-dimethyluric acid is the predominant excretory product. In addition, smaller amounts of 1-methyluric acid, 3-methylxanthine and unchanged theophylline were found. Excretory patterns after theophylline ingestion before and during the administration of allopurinol in asthma patients and in rats suggest the existence of three metabolic pathways of theophylline. The administration of this drug to a patient with xanthine oxidase of theophylline. The administration of this drug to a patient with xanthine oxidase deficiency resulted in the excretion of 1-methyluric acid in addition to 1,3-dimethyluric acid, 3-methylxanthine, 1-methylxanthine and unchanged theophylline. It was concluded that in man the oxidation of theophylline is not catalysed by xanthine oxidase. 相似文献
967.
968.
I Kitagawa A Matsuda T Nishimura S Hirai I Yoshioka 《Chemical & pharmaceutical bulletin》1967,15(9):1435-1437
969.
A new pyridine synthesis has been found by refluxing certain simple secondary car☐amides in HMPA. Thus 2,6-dimethylpyridine, 2-ethyl-6-methylpyridine, 2,3,6-trimethylpyridine, 2-ethyl-3,6-dimethylpyridine, 2-benzyl-6-methyl-3-phenylpyridine, 2-ethyl-3-methyl-5,6,7,8-tetrahydroquinoline and 2-t-butyl-6-methylpyridine were prepared in 15–40% yield. 相似文献
970.