Preparation of chiral α-diazophosphonic acid derivatives

The chiral α-diazophosphonic acid derivatives 3, 6 and 8 were prepared from (−)-ephedrine and (S,S)-N,N′-dimethyl-1,2-diaminocyclohexane; preliminary experiments suggest that the chiral auxiliary exerts little influence in the dirhodium(II) acetate catalysed OH and NH insertion reactions.     

Cyclization of N-(2,4,6-trimethylphenyl)-β-alanines

Reaction of 2,4,6-trimethylaniline with acrylic and itaconic acids gives the corresponding N-substituted =alanines which can be converted to derivatives of tetrahydropyridone, dihydropyrimidinedione, and 4-carboxy-2-pyrrolidinone. Bromination of the aromatic substituent in the synthesized heterocycles has been carried out.Kaunas Technological University, Kaunas 3028, Lithuania Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 951–954, July, 2000     

Syntheses of quinolines and their derivatives from α,β-unsaturated aldehydes

Chemistry of Heterocyclic Compounds - The methods for the synthesis of quinoline and its hydrogenated derivatives from α,β-unsaturated aldehydes have been summarized for the first time....     

β-Nitro derivatives of iron corrolates

Two different methods for the regioselective nitration of different meso-triarylcorroles leading to the corresponding β-substituted nitrocorrole iron complexes have been developed. A two-step procedure affords three Fe(III) nitrosyl products-the unsubstituted corrole, the 3-nitrocorrole, and the 3,17-dinitrocorrole. In contrast, a one-pot synthetic approach drives the reaction almost exclusively to formation of the iron nitrosyl 3,17-dinitrocorrole. Electron-releasing substituents on the meso-aryl groups of the triarylcorroles induce higher yields and longer reaction times than what is observed for the synthesis of similar triarylcorroles with electron-withdrawing functionalities, and these results can be confidently attributed to the facile formation and stabilization of an intermediate iron corrole π-cation radical. Electron-withdrawing substituents on the meso-aryl groups of triarylcorrole also seem to labilize the axial nitrosyl group which, in the case of the pentafluorophenylcorrole derivative, results in the direct formation of a disubstituted iron μ-oxo dimer complex. The influence of meso-aryl substituents on the progress and products of the nitration reaction was investigated. In addition, to elucidate the most important factors which influence the redox reactivity of these different iron nitrosyl complexes, selected compounds were examined by cyclic voltammetry and thin-layer UV-visible or FTIR spectroelectrochemistry in CH(2)Cl(2).     

Synthesis and Cyclization of N-(4-Phenoxyphenyl)-β-alanines

We have used the reaction of 4-aminodiphenyl ester with acrylic, methacrylic, crotonic, and itaconic acids to synthesize N-substituted -alanines, which undergo ring closure to form derivatives of dihydropyrimidinedione and 4-carboxy-2-pyrrolidinone. We have studied the reactions of acylation and recyclization of the dihydropyrimidinedione ring, and we have synthesized derivatives of 4-carboxy-1-(4-phenoxyphenyl)-2-pyrrolidinone: arylidene hydrazides, 2[(2-oxo-4-pyrrolidinyl-1-(4-phenoxyphenyl)]benzimidazole.     

Reaction of aminoquinolines with unsaturated carboxylic acids. 2. Cyclization of N-quinolyl-β-alanines

The cyclization of N-(3-quinolyl)- and N-(6-quinolyl)--alanines was carried out to give uncondensed hexahydropyrimidine derivatives, while the cyclization of N-(5-quinolyl)- and N-(8-quinolyl)--alanines gave tetrahydrophenanthrolinone derivatives.Communication 1, see ref. [1].Kaunas Technological University, 3028 Kaunas, Lithuania, Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 653–657, May, 2000.     

Preparation of novel multifunctional amino alcohols from nitroparaffins and α,β-unsaturated aldehydes

A series of novel multifunctional amino alcohols were prepared by tandem Michael–Henry reaction by reacting nitroalkanes such as 2-nitropropane with readily available α,β-unsaturated aldehydes. The dinitro compounds were further reduced by catalytic hydrogenation to obtain respective diamines. This synthetic route provides a very convenient method of preparing multifunctional amino alcohols.     

Preparation and properties of derivatives of dithiolylidene-(4′-phenyldiazonium)acetonitrile

Thefluoroborates of (4,5-dimethyl-1,3-dithiolylidene)-(4-phenyldiazonium)acetonitrile and (4,5-ethylenedithio-1,3-dithiolylidene)-(4-phenyldiazonium)acetonitrile have been prepared; these compounds are photosensitive in the visible region of the spectrum. The quantum yield in the photolysis of the fluoroborates in acetonitrile solution amounts to 0.1 moteleinstein.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, p. 179–181, February, 1994. Original article submitted November 29, 1993.     

Preparation of dehydromorpholines from β-cyanoethyl ethers of acetylenic alcohols

Summary A method has been developed for the synthesis of dehydromorpholines from-cyanoethyl ethers of acetylenic alcohols.     

Synthesis of phosphorylated derivatives of furoylglycine and furoyl-β-alanine

Chloromethylfuroyl chlorides react with alkyl glycinates and β-alanates to form the corresponding chloromethylfuroyl amides. The compounds obtained are phosphorylated with triethyl phosphite under the conditions of the Arbuzov reaction to give (diethoxyphosphorylmethylfuroyl amides. Alkaline hydrolysis of these compounds proceeds only at the carboxy group leading to (diethoxyphosphorylmethyl)furoylglycine and furoyl-β-alanine. Selectivity of hydrolysis does not depend on the position of carboxamide and diethoxyphosphorylmethyl groups in the furan ring.     

Practical Preparation of Resveratrol 3-O-β-D-Glucuronide

Abstract

A practical synthesis of resveratrol 3-O-β-D-glucuronide, suitable for preparation of large quantities, was developed using selective deacetylation of resveratrol triacetate with ammonium acetate. A simplified procedure for large-scale preparation of resveratrol is also reported.     

Preparation of Trans-β-Acyl Cyclopentanols and Cyclohexanols

The utility of organoboranes in the synthesis of a wide variety of functional groups is now well established.¹ There have been, however, only a limited number of reports where an organoborane containing a β-functionalized carbon was utilized in organic synthesis. Part of the reason for this is the difficulty in preparing β-functional organoboranes and their tendency to undergo elimination under a variety of reaction conditions.² Those β-functionalized organoboranes utilized synthetically, which we could find in the literature are the β-ethoxy³, 1, and β-carboethoxyvinyl-boranes⁴, 2, of Zweifel and coworkers and the trans-β-tert-butyldimethylsilyloxy organoborane, 3, of Corey and Ravindranathan,⁵ who proposed this system as a potential precursor to prostanoids.     

Synthesis and cyclization of N-(9-alkylcarbazol-3-yl)-β-alanines

The reaction of 3-amino-9-alkylcarbazoles with acrylic and itaconic acids yields N-substituted amino acids, which were converted into derivatives of 4-carboxy-2-pyrrolidinone and dihydropyrimidinedione.Kaunas Technological University 3028 Kaunas, LithuaniaTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1637–1640, November–December, 1999.     

Preparation and antibacterial activity of aromatic derivatives of β-aminopropionic and γ-aminobutyric acid

Ten aromatic derivatives of β-aminopropionic acid and γ-aminobutyric acid were prepared.Their compositions and structures were identified by elemental analysis,IR,and 1H NMR.They have been examined for their antibacterial action against Staphylococcua aurens and Escherichia coli.These compounds showed higher activity than the aromatic derivatives of ct-amino acid which were reported previously.The general conclusion to be drawn is that the distance between amino and carboxylic group in these molecules could affect their antibacterial activity.Furthermore,those compounds with p-methyl substituent in phenyl ring exhibit higher activity than the others,and all the compounds exhibit higher activity against Escherichia coli and against Staphylococcua aureus.     

New anthraquinone derivatives from the roots of Berchemia floribunda

A new naphthoquinone-anthraquinone dimer named floribundiquinone E(1)and a new anthraquinone 2-acetylphyscion(2)were isolated from the roots of Berchemia floribunda Brongn.Their structures were elucidated on the basis of spectroscopicmethods.     

Regiospecific synthesis of α-arylsulfonoxy ketones from ketone derivatives

Isomeric enol ester, enamine, and silyl enol ether derivatives of unsymmetrical ketones are converted regiospecifically to α-arylsulfonoxy ketones with arylsulfonyl peroxides.     

Two new α,β-unsaturated butyrolactone derivatives from Pleione bulbocodioides

Two newα,β-unsaturated butyrolactone derivatives,4-(4″-hydroxybenzyl)-3-(3′-hydroxy-phenethyl)furan-2(5H)-one(1)and 3-(3′-hydroxyphenethyl)furan-2(5H)-one(2),together with one known phenolic compound(3),were isolated from the tubers of Pleione bulbocodioides(Franch.)Rolfe.Their structures were elucidated by analysis of spectroscopic data.