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1.
Guoxiong Hua 《Tetrahedron》2009,65(31):6074-6987
2,4-Bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide (Woollins’ reagent, WR) reacts with cyanamides (1a-h) in refluxing toluene to afford a series of novel selenazadiphospholaminediselenides (RR′NCN(PhP(Se)SeP(Se)Ph, R=C6H5(CH2)1-3, 4-n-C10H21C6H4 and 4-BrC6H4CH2; R′=H, CH3, C2H5 and C(O)OC2H52a-g). Post-treatment of the reaction mixture with water led to the formation of carbamidoyl(phenyl)phosphinodiselenoic acids (RR′NC(NH2)P(SeH)2Ph, R=C6H5(CH2)2-3, 4-n-C10H21C6H4 and 4-BrC6H4CH2; R′=H and CH3, 3b, 3c, 3e and 3f) and selenoureas (RR′NC(Se)NH2, R=C6H5(CH)1-2; R′=CH3 and OC(O)C2H5, 4f and 4h) in moderate to excellent yields. All new compounds are characterised spectroscopically and five X-ray crystal structures are reported. 相似文献
2.
From amino acids to heteroaromatics--thiopeptide antibiotics, nature's heterocyclic peptides 总被引:1,自引:0,他引:1
Amino acids, the building blocks of proteins, also serve as precursors to a wide range of other naturally occurring substances including alkaloids, antibiotics, and, the subject of this Review, heterocyclic peptides. Simple alpha-amino acids are converted into complex arrays of heteroaromatic rings that display interesting and potent biological activity. The thiopeptide antibiotics, with their complex molecular architectures, are wonderful examples. In this Review we show how organic chemists have developed innovative methods for the synthesis of the heterocyclic ring systems, including routes inspired by the likely biosynthetic processes, and successfully assembled such building blocks into the final target molecule by application of orthogonal protecting groups and coupling methodologies. 相似文献
3.
J.M. Barrales-Rienda J.Gonzalez Ramos M.Sanchez Chavez 《Journal of fluorine chemistry》1977,9(4):293-308
A series of seven N-(fluoro phenyl) maleamic acids and their N-(fluoro phenyl) maleimides were prepared by the reaction of fluoro phenyl amines ( o-, m-, and p-fluoro, 2.4-, 2.5-difluoro, 2.3.5.6-tetrafluoro and 2.3.4.5.6.-pentafluoro anilines) with maleic anhydride according to substantial modifications made to the reaction conditions used by Searle for the preparation of normal N-aryl maleimides. 相似文献
4.
An efficient and practical decarboxylative cross-coupling reaction of quinolin-4(1H)-one 3-carboxylic acids with (hetero)aryl halides has been established. Under a bimetallic system of PdBr(2) and silver carbonate, the protocol proved to be general, and a variety of 3-(hetero)aryl 4-quinolinones and related heterocycles, such as 3-aryl-1,8-naphthyridin-4(1H)-ones, 3-arylcoumarins, 3-arylquinolin-2(1H)-ones, and 2-arylchromones, can be prepared in good to excellent yields. 相似文献
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R. R. Rakhmatullin O. A. Selyutina V. I. Gavrilov 《Russian Journal of General Chemistry》2007,77(11):1972-1974
The reaction between [chloro(phenyl)arsanyl]acetic and chloroacetic acids proceeds in alkaline aqueous medium by the Sn2 mechanism and is accompanied by alkaline hydrolysis of chloroacetic acid. Mean rate constants and thermodynamic parameters of the reaction are evaluated. 相似文献
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E. V. Sagadeev A. A. Gimadeev D. V. Chachkov V. P. Barabanov 《Russian Journal of General Chemistry》2012,82(8):1438-1439
Using a set of computational methods we calculated the basic thermochemical characteristics of the fifteen non-typical L-??-amino acids of hydroxyaminocarboxylic and thioaminomonocarboxylic series, and of some heterocyclic amino(imino)carboxylic acids. 相似文献
9.
The corresponding amino esters and their complexes with 7,7,8,8-tetracyanoquinodimethane were obtained by the condensation of the acid dichlorides of furan-2,5-dicarboxylic acid and tetrahydrothiophene-2,5-dicarboxylic acid with 8-hydroxy- and 5,7-dibromo-8-hydroxyquinolines. Almost all of the compounds obtained have antimicrobial activity.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 538–540, April, 1972. 相似文献
10.
E. V. Sagadeev A. A. Gimadeev D. V. Chachkov V. P. Barabanov 《Russian Journal of General Chemistry》2009,79(7):1490-1493
With the use of a complex of calculation methods the basic thermochemical characteristics of ten standard L-α-amino acids
of diaminomonocarboxylic, hydroxyaminomonocarboxylic, and thioaminomonocarboxylic series as well as of a series of heterocyclic
amino(imino)carboxylic acids were calculated. 相似文献
11.
The corresponding amino esters and their hydrochlorides and quaternary salts were obtained by the condensation of 2,5-furan- and 2,5-tetrahydrothiophenedicarboxylic acid chlorides with 1-methyl-, 1-ethyl-, or 1-butyl-3-hydroxypiperidines.deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 515–518, April, 1971. 相似文献
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A new method of introducing the 1H-indol-3-yl(phenyl)methyl residue into some CH acids was developed. 相似文献
14.
R. Nurdinov É. É. Liepin'sh I. B. Mazheika I. Ya. Kalvin'sh 《Chemistry of Heterocyclic Compounds》1993,29(9):1093-1098
By the interaction of esters of L-proline, L-thioproline, pipecolic acid, and tetrahydro-1,4-thiazine-3-carboxylic acid with hydrazine, the corresponding hydrazides were obtained, which react with equimolar quantities of carbonyl compounds to form hydrazones consisting of mixtures of rotational isomers relative to the amide bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1277–1282, September, 1993. 相似文献
15.
Stanley C. Bell Carl Gochman Peter H. L. Wei 《Journal of heterocyclic chemistry》1975,12(6):1207-1210
A number of thiazolo 5-carboxylic acid derivatives were prepared which were fused to other heterocycles such as 1,2,4-benzothiadiazine, quinazoline, and pyrimidine rings at the 2,3-position of the thiazole ring. In several instances unexpected products were obtained, depending on the reaction conditions. The chemistry of these reactions and the identification of the products are discussed. 相似文献
16.
A.R. Lister 《Tetrahedron》2006,62(43):10208-10214
A series of poly(phenyl ketone) dendrons have been constructed using a convergent strategy. An aryl fluoro-substituent is deactivated towards nucleophilic substitution by protection of a para-ketone as an acetal. This allows coupling to an activated aryl fluoride.Subsequent deprotection of the acetyl group then activates the first fluoro-substituent and allows the next generation of the dendron to be added. The synthesis of higher generations is complicated by a scrambling reaction, which lowers the yields. 相似文献
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G. B. Afanas'eva V. I. Vysokov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1989,25(8):841-858
Data on the reactions of phenazine, phenoxazine, and phenothiazine derivatives in which the bridge nitrogen atom is included in a quinoneimine fragment are correlated. The effect of the nature of the second bridge heteroatom, benzo annelation, and activation of the substrate and the reagent on the reactivities of the heterocyclic quinoneimines cited above is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1011–1030, August, 1989. 相似文献
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