Novel heterocyclic selenazadiphospholaminediselenides, zwitterionic carbamidoyl(phenyl)-phosphinodiselenoic acids and selenoureas derived from cyanamides

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.     

From amino acids to heteroaromatics--thiopeptide antibiotics, nature's heterocyclic peptides

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.     

Synthesis of N-(fluoro phenyl) maleamic acids and N-(fluoro phenyl) maleimides

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.     

Palladium-catalyzed decarboxylative coupling of quinolinone-3-carboxylic acids and related heterocyclic carboxylic acids with (hetero)aryl halides

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.     

Kinetics of the reaction between [chloro(phenyl)arsanyl]acetic and chloroacetic acids

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.     

Empirical and ab initio calculations of thermochemical parameters of amino acids: IV. Non-Typical amino acids: Hydroxyamino acids, thioamino acids, and heterocyclic amino(imino) acids

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.     

Amino esters of heterocyclic dicarboxylic acids

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.     

Empirical and ab initio calculations of thermochemical parameters of aminoacids: II. Diaminomonocarboxylic acids,hydroxyamino acids,thioamino acids,and heterocyclic amino(imino) acids

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.     

Amino esters of heterocyclic dicarboxylic acids

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.     

4-羟甲基-N-(4-乙氧基苯基)-N-(4'-硝基苯基)苯胺的合成

以碘化亚铜为催化剂,对硝基苯胺与对碘苯乙醚经取代反应制得4-乙氧基-N-(4-硝基苯)苯胺(1);1与对氟苯甲醛在碳酸钾作用下经取代反应制得4-(N-4-硝基苯-N-4-乙氧基苯)氨基苯甲醛(2);2经Na BH4还原合成了新化合物4-羟甲基-N-(4-乙氧基苯基)-N-(4'-硝基苯基)苯胺,其结构经1H NMR,13C NMR和IR表征。     

Introduction of the 1H-indol-3-yl(phenyl)methyl residue into some CH acids

A new method of introducing the 1H-indol-3-yl(phenyl)methyl residue into some CH acids was developed.     

Derivatives of heterocyclic α-iminocarboxylic acids. 1. Syntheses of hydrazides of heterocyclic α-iminocarboxylic acids and their hydrazones

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.     

Syntheses of heterocyclic fused thiazolecarboxylic acids I

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.     

A convergent route to poly(phenyl ketone ether) dendrons

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.     

Reactivities of heterocyclic quinoneimines (review)

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.