DIASTEREOSELECTIVE SYNTHESIS AND STEREOCHEMISTRY OF (Z)-1-[3-ARYL-2-(PHENYLSULFANYL)-2-OXIRANYL]-1-ETHANONES

Diastereoselective synthesis of a series of (Z)-1-[3-aryl-2-(phenylsulfanyl)-2-oxiranyl]-1-ethanones was effected from the reaction of (Z)-4-aryl-3-(phenylsulfanyl)-3-buten-2-ones with alkaline hydrogen peroxide in tetrahydrofuran. The stereochemistry of the oxiranes has been deduced from two-dimensional NOESY spectrum.     

Synthesis and Alkylation of Piperidinium 4,5-trans-3-Cyano-6-hydroxy-4-(2-iodophenyl)-6-methyl-5-(2-methylphenyl)carbamoyl-1,4,5,6-tetrahydropyridine-2-thiolate. Molecular and Crystal Structure of 3-(2-Iodophenyl)-2-(4-phenyl-2-thiazolyl)acrylonitrile

The reaction of o-iodobenzaldehyde, cyanothioacetamide, and N-acetoacetyl-o-toluidine in the presence of piperidine gave piperidinium 4,5-trans-3-cyano-6-hydroxy-4-(2-iodophenyl)-6-methyl-5-(2-methylphenyl)carbamoyl-1,4,5,6-tetrahydropyridine-2-thiolate used in the synthesis of substituted 4,5-trans-2-alkylthiotetrahydropyridines and 2-(2-thiazolyl)acrylonitriles. The structure of 3-(2-iodophenyl)-2-(4-phenyl-2-thiazolyl)acrylonitrile was studied using X-ray diffraction structural analysis.     

Preparation of 3-Aryl-4-(5-ARYL-Δ2-1,2,4-Oxadiazolin-3-YL)Sydnones and their Conversion into 3-ARYL-4-(5-ARYL-1,2,4-Oxadiazol-3-YL)Sydnones

3-Aryl-4-(5-aryl-Δ²-1,2,4-oxadiazolin-3-yl)sydnones (5) were synthesized in high yields by the reaction of 3-arylsydnone-4-carboxamide oximes (prepared from the corresponding 3-arylsydnone-4-carbonitriles) with aromatic aldehydes in the presence of acid catalysts. No reaction occurred when aliphatic aldehydes were used. The oxadiazolin-3-ylsydnones (5) were easily converted into the corresponding 3-aryl-4-(5-aryl-1,2,4-oxadiazol-3-yl)sydnones by N-bromosuccinimide oxidation. The 3-arylsydnone-4-carbonitrile oxides were synthesized in good yields by N-bromosuccinimide oxidation of the corresponding 3-arylsydnone-4-carboxaldehyde oximes.     

1-(2-苯并噻唑基)-3-苯基吡唑啉类化合物的合成

有机荧光化合物有多种结构类型,其中含氮唑系杂环类化合物可作为一些合成纤维和塑料制品的增白剂^[1～4]。据此,我们合成了一系列新的具有不同取代基的苯并噻唑基吡唑啉化合物,并观察了其荧光性质。     

Reaction of 2-(4-Arylthiazol-2-yl)-4-chloro-3-oxobutyronitriles with Secondary Aliphatic Amines

We have obtained 2-(4-arylthiazol-2-yl)-4-chloro-3-oxobutyronitriles by acylation of 4-aryl-2-cyanomethylthiazoles with -chloroacetyl chloride. We have studied their reaction with secondary aliphatic amines, leading to formation of 4-dialkylamino-2-(4-arylthiazol-2-yl)-3-oxobutyronitriles, and also intramolecular alkylation with formation of 3-aryl-7-cyano-6(5H)-oxopyrrolo[2,1-b]thiazoles. We have determined some aspects of the tautomerism of the synthesized compounds.     

1-偶氮苯-3-(6-甲氧基-2-苯并噻唑)-三氮烯光度法测定粉煤灰中微量锌

研究了1-偶氮苯-3-(6-甲氧基-2-苯并噻唑)-三氮烯(AMBT)与锌的显色反应,在pH11.0的Na2CO3-NaHCO3缓冲溶液中,TritonX-100存在下,AMBT与Zn(Ⅱ)反应生成2∶1稳定络合物,其最大吸收波长为535nm,表观摩尔吸光系数为8.37×104L.mol-1.cm-1。锌质量浓度在0~0.40μg/mL内符合比尔定律,方法用于测定粉煤灰中微量锌,结果与极谱法相符,RSD<3%。     

Pd-catalyzed synthesis of 3-(diarylmethylene)-2-oxindoles and 3-(arylmethylene)-2-oxindoles

An efficient method for the stereoselective synthesis of 3-(diarylmethylene)-2-oxindoles and 3-(arylmethylene)-2-oxindoles via carbopalladation is described. In this approach, an Ugi-4-component reaction (4-CR) adduct was used as the starting material. A one-pot sequence involving intermolecular carbopalladation C-H activation/C-C bond formation efficiently afforded the oxindole derivatives.     

3-(2-Quinolyl)- and 3-(5-carbethoxyfuryl-2)coumarins

3-(2-Quinolyl)- and 3-(5-carbethoxyfuryl-2)coumarins were prepared by reaction of substituted salicylaldehydes and hetarylacetonitriles. Alkylation and acylation of 3-hetaryl-7-hydroxycoumarins were studied. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 432–434, September–October, 2005.     

Polyfunctional pyrazoles. 4. Synthesis of 3-[3-aryl-1-(2-ethoxycarbonyl)-4-pyrazolyl]acrylic and-propionic acids

3-(3-Aryl-4-formyl-1-pyrazolyl)propionic acids are converted by Knoevenagel condensation under conditions of microwave activation into 3-[3-aryl-1-(2-ethoxycarbonyl)-4-pyrazolyl]acrylic acids. Reduction of the latter with hydrazine hydrate in the presence of Raney nickel gives 3-[3-aryl-1-(2-ethoxycarbonyl)-4-pyrazolyl]propionic acids. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 686–690, May, 2006.     

Carbon-13 NMR Studies of 3-Aryl-4-(5-aryl-Δ 2-1,2,4-oxadiazolin-3-yl)sydnones and 3-Aryl-4-(5-aryl-1,2,4-oxadiazol-3-yl)sydnones

The ¹³C NMR spectra of twelve 3-aryl-4-(5-aryl-Δ²-l,2,4-oxadiazolin-3-yl)sydnones and twelve 3-aryl-4-(5-aryl-l,2,4-oxadiazol-3-yl)sydnones have been measured and assigned by means of proton-noise decoupling and DEPT-experiments. The coupling constants were determined by means of gated decoupling, and NOE effects were observed by comparison of proton-decoupled and inverse-gated decoupled spectra. Differences shown by the oxadiazoline and the oxadiazole rings and the substitution effects are discussed.     

Synthesis of 6-amino-4-aryl-5-cyano-3-(3-cyanopyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles and their hydrogenated analogs. Molecular structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole

Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis.     

Polyfunctional pyrazoles. 3.* Synthesis of 3-(3-aryl-4-formyl-1-pyrazolyl)propionic acids and their amides

3-(3-Aryl-4-formyl-1-pyrazolyl)propionic acids were synthesized by the reaction of 3-aryl-1-(2-cyanoethyl)-4-formylpyrazoles with concentrated hydrochloric acid. They were converted into the corresponding amides by the carbodiimide method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1483–1486, October, 2004.For Communication 2, see [1].     

Synthesis of Novel New 2-(2-(4-((3,4-Dihydro-4-oxo-3-aryl quinazolin-2-yl)methyl)piperazin-1-yl)acetoyloxy)-2-phenyl Acetic Acid Esters

Stereoselective diazotization of (S)-2-amino-2-phenyl acetic acid (L-phenyl glycine) (4) with NaNO₂ in 6% H₂SO₄ in a mixture of acetone and water gave optically pure (S)-2-hydroxy-2-phenyl acetic acid (L-mandelic acid) (5). Esterification, gave (S)-2-hydroxy-2-phenyl acetic acid esters (6). The latter was treated with chloroacetyl chloride in the presence of triethylamine (TEA) in dichloromethane (DCM) to yield (S)-2-chloroacetyloxy phenyl acetic acid ester (2). In another sequence, the reaction of 2-(chloromethyl)-3-arylquinazolin-4(3H)-one (9) treated with N-Boc piperazine, followed by deprotection of the Boc group, to obtain 3-aryl-2-((piperazin-1-yl)methyl) quinazolin-4(3H)-one (3). Reaction of 2 with 3 in the presence of K₂CO₃ and KI gave the title compound, 2-(2-(4-((3,4-dihydro-4-oxo-3-arylquinazolin-2-yl)methyl)piperazin-1-yl) acetoyloxy)-2-phenyl acetic acid esters (1). The structures of all the new compounds obtained in the present work are supported by spectral and analytical data.     

Reaction of 2-(2-Azahetaryl)-4-chloro-3-oxobutyronitriles with Substituted Benzaldehyde Hydrazones. Unexpected Formation of 4-Arylideneamino-2-(1-R-benzimidazol-2-yl)-3-oxobutyronitriles

The reaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutyronitriles with substituted benzaldehyde hydrazones gives 4-arylideneamino-2-(1-R-benzimidazol-2-yl)-3-oxobutyronitriles, the structures of which were proved using spectroscopic data, the results of elemental analysis, and through their chemical reactions. It was found that the reaction course depends on the basicity of the heterocyclic fragment in the starting nitrile. A likely mechanism for the process is proposed.     

Reaction of 2-(2-oxoethylidene)furan-3(2H)-ones with isopropylidenehydrazides of aromatic carboxylic acids: Synthesis of 3-hydroxy-3-(2-oxoethyl)-2,3-dihydropyridazin-4(1H)-ones

3-Hydroxy-3-(2-oxoethyl)-6-phenyl-2,3-dihydropyridazin-4(1H)-ones were obtained by the reaction of methyl 3-oxo-5-phenylfuran-2(3H)-ylideneacetate or 2-[2-(4-chlorophenyl)-2-oxoethylidene]-5-phenylfuran-3(2H)-one with benzoic or p-nitrobenzoic isopropylidenehydrazides. Equilibrium C₍₅₎H and C₍₅₎H₂ tautomeric forms were detected in solutions of the 4-chlorophenyl derivatives in DMSO-d₆. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1156–1158, August, 2007.     

Synthesis of Functionalized (2-Thienylcarbonyl)thiazoles and 4-(2-Thienyl)pyridines by Reaction of (2-Thienylcarbonyl)thioacetanilides and their Enamine Derivatives

Summary. The condensation of two molecules of 2-(2-thienylcarbonyl)thioacetanilides catalyzed by piperidine yielded thiazole derivatives as confirmed by X-ray crystal structure analysis. The reaction of malononitrile with 3-morpholino-3-(2-thienyl)acrylic acid thioanilides furnished 6-amino-1-aryl-4-(2-thienyl)-1,2-dihydro-2-thioxopyridine-5-carbonitriles. A similar reaction of malononitrile with 3-morpholino-3-(2-thienyl)acrylic acid anilides provided 2-oxopyridine-5-carbonitriles.     

3-(2-Pyridyl)coumarins

3-(2-Pyridyl)coumarins were prepared by reaction of substituted salicylaldehydes and 2-pyridylacetonitrile. Benzylation, acylation, and aminomethylation of 7-hydroxy-3-(2-pyridyl)coumarin was studied. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 428–431, September–October, 2005.     

3-(Benzimidazolyl-2)-2-iminocoumarins in Reactions with Aromatic Aldehydes

Interaction of 3-(benzimidazolyl-2)-2-iminocoumarins with aromatic aldehydes in the presence of piperidine gave the corresponding 7-aryl-7H-benzo[4,5]imidazo[1,2-c]benzopyrano[3,2-e]pyrimidines. The 3-diethylamino derivatives of this series fluoresce effectively in alcohol solutions.     

Novel (E)- and (Z)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles from (E)- and (Z)-3-styrylchromones: the unexpected case of (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles

An efficient synthetic method for the preparation of (E)- and (Z)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles has been developed. The reaction of (E)- and (Z)-3-styrylchromones with hydrazine hydrate afforded the corresponding (E)- and (Z)-4-styrylpyrazoles, respectively, saved 4′-nitro-derivatives where both (E)- and (Z)-4′-nitro-3-styrylchromones afforded (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles. The reaction mechanism for these transformations was discussed and the stereochemistry of all products was assigned by NMR experiments.     

Camps reaction for the synthesis of 3-RS-4-arylquinolin-2-ones

The replacement of the chlorine atom in 2-(chloroacetamido)benzophenones on treatment with RSH (R = Alk, Ar, Hetaryl) in the presence of MeONa is accompanied by intramolecular cyclization following the Camps reaction pattern to give 3-RS-4-arylquinolin-2-ones. Cleavage of 4-aryl-3-(benzoxazol-2-ylthio)quinolin-2-ones by morpholine has resulted in the corresponding 4-aryl-3-mercaptoquinolin-2-ones.