A. A. Avetisyan

Syntheses on the Basis of 4-(Oxiran-2-ylmethyl)morpholine

Abstract4-(Oxiran-2-ylmethyl)morpholine was synthesized and converted into new morpholino derivatives of propan-2-ols and butan-4-olides.

Asymmetric synthesis of (R)-S-(1,2,4-triazol-3-yl)cysteines by nucleophilic addition of triazolethiols to a NiII complex with a chiral dehydroalanine Schiff base

An efficient method was developed for the asymmetric synthesis of (R)-S-(1,2,4-triazol-3-yl)cysteines by the addition of 3,4-disubstituted 1,2,4-triazole-5-thiols at the electrophilic C=C bond in a NiII complex of a Schiff base of dehydroalanine with (S)-N-(N-benzylprolyl)aminobenzophenone. The stereoselectivity of the formation of diastereomeric complexes with the (S,R) configuration under conditions of thermodynamic control of the nucleophilic addition exceeds 94%. Acid treatment of the reaction mixtures afforded enantiomerically pure (R)-S-hetarylcysteines (ee >98%).

Synthesis of new 2-substituted 2,5-dihydrofuranone derivatives and their chemical transformations

2,5-Dihydrofuran-2-ones having functional substituents in the 3-position constitute structural fragments of many natural and synthetic biologically active compounds [1–5]. One of the most general and convenient methods of synthesis of functionally substituted furan2(5H)-ones is based on reactions of α-hydroxy ketones with compounds containing an activated methylene group [6–8]. In continuation of our studies in this field, in the present communication we report on the synthesis and chemical transformations of a new class of compounds, 2,5-dihydrofuran-2-imines based on readily accessible α-hydroxy ketones. We found that, contrary to published data [9], tertiary α-hydroxy ketones react with malononitrile to give mixtures of the corresponding 2,5-dihydrofuran-2-imines I and products of their subsequent reaction with the second malononitrile molecule, 2-(2,5-dihydrofuran-2-ylidene)malononitriles II, which were formed in good yields. Detailed examination of this reaction with a view to find optimal conditions showed that the process occurs even in the absence of a catalyst upon mixing of the reactants in alcohol or benzene. General procedures for the reactions of α-hydroxy ketones with malononitrile. a. The corresponding α-hydroxy ketone and malononitrile, 50 mmol each, were added to a solution of 0.115 g (5 mmol) of metallic sodium in 25 ml of anhydrous ethanol. The mixture was kept for 15–20 h at room temperature, the solvent was distilled off under reduced pressure, the residue was dissolved in benzene, and the precipitate was filtered off and recrystallized from ethanol–water (2 : 1) to isolate compound IIa or IIb. The benzene solution was diluted with four volumes of hexane, and the precipitate was filtered off and recrystallized from heptane. We thus isolated compound Ia or Ib. b. A mixture of 50 mmol of α-hydroxy ketone and 50 mmol of malononitrile in 25 ml of anhydrous ethanol was kept for 15–20 h at room temperature. The mixture was then treated as described above in a. c. A mixture of 50 mmol of α-hydroxy ketone and 50 mmol of malononitrile in 25 ml of anhydrous benzene was kept for 15–20 h at room temperature. The solvent was partially distilled off under reduced pressure, and the mixture was then treated as described above in a.

Synthesis of functionally substituted 2-imino-3-aryl-2,5-dihydrofurans and their chemical reactiosns

3-Functionalized 2(5H)-furanones are known to be contained in the composition of many biologically active compounds and are widely applied in the medicine, agriculture, perfumery, etc. [1]. Depending on the character of substituents the derivatives of 2(5Н)-furanones exhibit various pharmacological actions [2–4]. In our previous publications we reported on the structure and the process of the formation of the corresponding substituted 2,5-dihydrofurans by condensation of α-ketols with the amides of cyanoacetic acid [5] and with malononitrile [6]. Unlike the reaction with the amides of cyanoacetic acid the reaction of α-ketols with the malonodinitrile led to the simultaneous formation in good yields of two types of compounds, 2-imino derivatives of the corresponding dihydrofurans, and the products of their further reaction with the malonodinitrile, 2-dicyanomethylenedihydrofurans [6]. In extension of the research on the synthesis of new functionally substituted derivatives of 2,5-dihydrofurans and aiming at the preparation of 2-imino derivatives containing aromatic substituents in the position 3 we investigated in this study the reactions of α-ketols with aromatic nitriles. In this reaction unlike that with the malononitrile only 2-imino-3-aryl-4-methyl-5,5substituted2,5-dihydrofurans Iа–Id formed in high yields (up to 90%). Various factors were studied affecting the course of the reaction, optimum conditions were developed, and it was established that the process easily occurred at room temperature and equimolar amounts of the reagents in the presence of a catalytic quantity of sodium ethylate (1 : 1 : 0.1) in contrast to data of [7] where the sodium ethylate was used in an equimolar amount as a reagent, and the reaction was carried out under the microwave activation (250 MHz, 100 W). The reaction of 2-imino derivatives Iа–Id with malononitrile in the ratio 1 : 1 at room temperature in benzene or ethanol within ~20 h furnished in nearly quantitative yield the corresponding 2-dicyanomethylene derivatives IIа–IId.

Convenient Synthesis of Cerpegin

A convenient procedure for the preparation of cerpegin is described.

Synthesis of new 3-phenoxypropan-2-ols with various heterocyclic substituents

Abstract1-Phenoxy-3-piperidinopropan-2-ol, 1-(5-methyl-1,3-benzothiazol-2-ylsulfanyl)-3-phenoxypropan-2-ol, 1-(2-hydroxy-3-phenoxypropyl)azepan-2-one, 1,1′-(6-chloro-1,3-benzothiazol-2-ylimino)bis(3-phenoxypropan-2-ol), 1-(1,3-benzothiazol-2-ylsulfanyl)-3-phenoxypropan-2-ol, 1,1′-(piperazine-1,4-diyl)bis(3-phenoxypropan-2-ol), and 1,3-bis(2-hydroxy-3-phenoxypropyl)barbituric acid were synthesized by condensation of 1,2-epoxy-3-phenoxypropane with the corresponding amines and thiols.

Convenient synthesis of 2-imino-3-(2-thienyl)-2(5H)-furans and their certain transformations

A convenient and effi cient method was described of the preparation of 2-imino-3-(2-thienyl)-2,5-dihydrofurans by the condensation of α-ketol with the thiophene-2-acetonitrile and some their chemical transformations were performed.

Syntheses proceeding from N-(oxiran-2-ylmethyl)-N-ethylaniline

The preparation of N-(oxiran-2-ylmethyl)-N-ethylaniline was developed. The compound was used in the synthesis of new N-derivatives of aromatic amines containing vicinal aminoalcohol moieties.

Syntheses on the Basis of Diethyl (2-Morpholinoethyl)malonate

New functionally substituted butan-4-olides were synthesized by reactions of diethyl (2-morpholinoethyl) malonate with 2-(allyloxymethyl)oxirane, 4-(oxiran-2-ylmethyl)morpholine, N-ethyl-N-(oxiran-2-ylmethyl)aniline, and 1-chloro-2,3-epoxypropane. 5-[2-(Morpholino)ethyl]barbituric and -thiobarbituric acids were also synthesized.

New syntheses on the basis of 4-hydroxy-2H-chromen-2-ones

Alkylation of 4-hydroxy-2H-chromen-2-ones with 2-chloromethyloxirane in acetone in the presence of potassium carbonate gave 4-(2,3-epoxypropoxy)-2H-chromen-2-ones which were treated with various amines to obtain the corresponding 4-(3-amino-2-hydroxypropoxy)-2H-chromen-2-ones, and the latter were acylated at the hydroxy group with benzoyl chloride.