in the present study, an attempt has been made to synthesize 3-methyl-4-arylmethylene isoxazole-5(4h)-one derivatives through sonication of hydroxylamine hydrochloride, ethyl acetoacetate and benzaldehyde derivatives in the presence of imidazole as a novel and effective catalyst in aqueous media. this green reaction under ultrasound irradiation has advantageous compared to conventional procedur...

Article history: Received on: 08/11/2014 Revised on: 22/11/2014 Accepted on: 18/12/2014 Available online: 29/12/2014 A series of new thiopyrimidine derivatives were synthesized via the reaction of ethyl cyanoacetate with thiourea and the appropriate aldehydes namely, 3-methoxy-benzaldehyde, 2, 5-dimethoxy-benzaldehyde and 3,5dimethoxy-benzaldehyde to give the corresponding pyridine thiones 1a-c...

A transaminase from Halomonas elongata and four mutants generated by an in silico-based design were recombinantly produced in E. coli, purified and applied to the amination of mono-substituted aromatic carbonyl-derivatives. While benzaldehyde derivatives were excellent substrates, only NO2-acetophenones were transformed into the (S)-amine with a high enantioselectivity. The different behaviour ...

Reaction of heteroaromatic o-aminonitrile with ethyl N-[bis(methylthio)methylene]amino acetate resulted in annelation of a thieno[3,2-e]imidazo[1,2-c]pyrimidine moiety in a one step process. [1,2,4]Triazolo[4,3-c]thieno- [3,2-e]pyrimidine derivatives were prepared by initial treatment of o-aminonitrile with carbon disulfide, followed by methylation with methyl iodide and subsequent reaction wit...

In the present study, an attempt has been made to synthesize 3-methyl-4-arylmethylene isoxazole-5(4H)-one derivatives through sonication of hydroxylamine hydrochloride, ethyl acetoacetate and benzaldehyde derivatives in the presence of imidazole as a novel and effective catalyst in aqueous media. This green reaction under ultrasound irradiation has advantageous compared to conventional...

A novel hybrid catalyst based on grafting Cu on furfural imine-functionalized halloysite was designed, characterized and used for promoting synthesis of xanthene derivatives via three- component reaction of benzaldehyde derivatives, dimedone, and β-naphthol in aqueous media and under mild reaction condition. The results established high catalytic activity of the hybrid system, which was superio...

A novel hybrid catalyst based on grafting Cu on furfural imine-functionalized halloysite was designed, characterized and used for promoting synthesis of xanthene derivatives via three- component reaction of benzaldehyde derivatives, dimedone, and β-naphthol in aqueous media and under mild reaction condition. The results established high catalytic activity of the hybrid system, which was superio...

barium salts of dibenzylidene cystines 8a-c were obtained from the reaction of lcystine with benzaldehyde or its derivatives in the presence of barium hydroxide. their reduction with zinc and hydrochloric acid in methanol yielded the narylmethylcysteines ?9a-c?. these can, in turn, be converted by esterification into the methyl esters ?10 a-c. ?reaction of n, n'-carbonyl diimidazole (im co...

Palladium catalysed carbonylation reactions using the meta- and para-iodo derivatives of all-cis-3-phenyl-1,2,4,5-tetrafluorocyclohexane (4) are illustrated as the start point for a variety of functional group interconversions. The resultant benzaldehyde and benzoic acids offer novel building blocks for further derivatisation and facilitate the incorporation of the facially polarised all-cis-1,...

A new phenolic compound, named 3-geranyl-2,5-dihydroxy-benzaldehyde (1), together with seven known chalone derivatives (2–8) has been isolated from the seeds of Celosia cristata L. Their chemical structures have been elucidated by spectroscopic analysis. All these compounds (1–8) were isolated from C. cristata for the