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991.
Conclusions A method of synthesis of arylhydroxyacetic acids and ammo acids derived from ethinylphenols has been developed in view of possible physiological activity of these compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1170–1172, May, 1970.  相似文献   
992.
The mass spectra of twenty-six commercially available medicinal phenothiazines have been determined at high resolution. In each compound, the side chain attached to the 10-position of the phenothiazine ring contains nitrogen and fission of the C? C bond α to this nitrogen gives in most cases the base peak. Some of the compounds are also substituted at the 2-position and this substituent generally remains intact, though some substituents such as acetyl, propionyl, methoxyl and methylthio can undergo fragmentation. Fragmentations fall into three groups; those which give ions representing a part of the side chain; those which give ions representing the intact phenothiazine ring with part of the side chain attached; those which give ions representing a partially fragmented ring system.  相似文献   
993.
Conclusions The reactions of amides of arylphosphorous acids with acyl chlorides take place with replacement of the amide group and formation of amides of carboxylic acids and the corresponding aryl chlorophosphates.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2131–2133, September, 1968.  相似文献   
994.
Optimum conditions have been established for formation and extraction of indium-Rhodamine complexes, and limits of detection found for fluorimetric determination of gallium and indium by means of Rhodamine dyes, using the excitation with pulsed laser and xenon arc sources.  相似文献   
995.
2,3-Polymethylene-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine derivatives were obtained by reaction of esters of α-aminothiophene-β-carboxylic acids with lactame or α-aminothiophene-Β-carboxylic acids with lactims. Desulfuration of the thienopyrimidines obtained in this manner is a convenient method for the synthesis of pyrrolo-, pyrido-, and azepino[1,2-a]pyrimidine derivatives.  相似文献   
996.
The theoretically estimated dipole moments of indolizine, imidazo[1,2-a]pyridine, imidazo-[1,5-a]pyridine and of pyrazolo[ 1,5-a]pyridine obtained by the CNDO/2 approximation have been compared with the experimental values. The bond angles and bond distances for these polyazaindenes have been estimated.  相似文献   
997.
The PMR, Raman, and UV absorption spectra of 2-hydroxypyridine and its vinyl derivatives were investigated. Their electrochemical reduction was studied, and a quantum-chemical analysis of them was performed. It was concluded that the structure of 2-hydroxypyridine in proton-donor solvents is mesomeric, and its wave function, to a first approximation, is a linear combination of the wave functions of the 2-pyridone and zwitterion models. The contribution of the wave functions of each of the models depends substantially on the concentration of the solution and the nature of the solvent. An assumption was made regarding the presence of dynamic conjugation between the vinyl group and the ring in vinyl derivatives of 2-hydroxypyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 95–102 January, 1972.  相似文献   
998.
2-R-Quinazolones have been synthesized (R=Me, Ph,-pyridyl,-furyl), and subsequently the 4-chlorides and the corresponding 2-R-4-hydrazinoquinazolines were obtained. By the reaction of orthoformic ester and nitric acid on the hydrazines, 5-R- [3, 4-c]-s-triazoloquinazolines and 5-R- [1, 5-c] tetrazoloquinazolines were prepared, respectively. The compounds in which R=Me differ considerably from compounds with other groups, both in color and stability of intermediate reaction products. 5-R- [1, 5-c] tetrazoloquinazolines are hydrolyzed by HCl into quinazol-4-ones.For Part IV see [1].  相似文献   
999.
In the interaction of ethioporphyrin and of several of its metal derivatives with negative ions of pyridine and anthracene in tetrahydrofuran solutions, an electron transfer takes place which results in the conversion of the pyridine and anthracene ions into neutral molecules, whereas the molecules of the pigment are first transformed into monovalent anions and subsequently into the di-, tri-, tetra-, and sometimes even into the hexavalent anions. In the first stage of this interaction, ferriethioporphyrin is reduced to ferro-ethioporphyrin, whereas the unmetallized pigment and its copper complex are transformed into the disodium derivative of ethioporphyrin. When the temperature is lowered, the rate of the electron transfer from pyridine ions to zinc-ethioporphyrin is decreased, and illumination leads to a substantial rate increase. The photochemical sensitivity of this system is possibly linked to the formation of stable complexes between pigment molecules and pyridine ions.  相似文献   
1000.
Block copolymers containing poly(tetramethylene oxide) and poly(methyl methacrylate) segments were prepared. A commercially available poly(tetramethylene oxide) terminated with tolylene diisocyanate was capped with tert-butyl hydroxymethyl peroxide and the resulting prepolymer peroxide was used as a free-radical initiator of vinyl polymerization. Block copolymers formed in temperature-programmed vinyl polymerizations possessed improved impact strengths over poly(methyl methacrylate) from 0.35 to 1.18 for a fixed (nonoptimized) block length of poly(tetramethylene oxide).  相似文献   
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