Microwave assisted synthesis and Anti-microbial activity of new Diethyl ((dialkoxyphosphoryl) (2-hydroxyphenyl) methyl) phosphoramidates

The synthesis of new α-aminophosphonates 4a-j (diethyl((dialkoxyphosphoryl)(phenyl)methyl)phosphoramidates) were achieved through a one pot simple and efficient method from the three-component condensation reaction (Kabachnik-Fields reaction) of diethyl phosphoramidate, aryl salicylaldehydes, and dialkyl phosphite by using microwave irradiation under solvent-free and catalyst-free conditions in good to excellent yields and short reaction times. The structures of the novel products were established by IR, ¹H, ¹³C & ³¹P-NMR and Mass spectroscopy. All the synthesized compounds were screened their antimicrobial activity.     

An expedient solvent-free C-benzylation of 4-hydroxycoumarin with styrenes

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Liquid crystal materials with ionic-surfactant operation

A conceptually new approach for developing methods of control of liquid crystals is discussed. The approach is based on modifying surface anchoring. A brief review of the authors’ research on developing ionic-surfactant control of liquid crystalline materials is described. This approach is based on the effect of electrically induced modification of the boundary conditions by ions of surface-active compounds.     

3,4,5,6-Tetrafluoro-1,2-dehydrobenzene in reactions with 1,2,4-triazines

Tetrafluoro-substituted aryne, 3,4,5,6-tetrafluoro-1,2-dehydrobenzene, has been generated in situ from 2-amino-3,4,5,6-tetrafluorobenzoic acid, and its reactivity in reactions with 1,2,4-triazines as dienes has been studied. In these reactions, the corresponding azine ring transformation products, i.e., 1,2,3,4-tetrafluoro-10-(1H-1,2,3-triazol-1-yl)pyrido[1,2-a]indoles, have been obtained, in the case of triazines activated by the presence of electron-withdrawing groups, such as 6-aryl-3-(2-pyridyl)-5-cyano-1,2,4-triazines. The crystal structure of the obtained products was confirmed by X-ray diffraction analysis.     

Synthesis of 8,10-dimethyl-1,10b-dihydro[1,3,5]triazino-[2,1-a]isoindole-2,4,6(3H)-trione by Direct arylation of 1,3,5-triazine-2,4(1H,3H)-dione

Direct arylation of 1,3,5-triazine-2,4(1H,3H)-dione with mesitylene afforded a novel fused heterocyclic system, 8,10-dimethyl-1,10b-dihydro[1,3,5]triazino[2,1-a]isoindole-2,4,6(3H)-trione.     

Experimental Solution of the Local Field Problem in Uniaxial Liquid Crystals†

A method of experimental determination of the Lorentz-factor tensor in uniaxial liquid crystals is suggested. The specific features of the local field tensor of the light wave in a nematic liquid crystal with low optical anisotropy have been investigated experimentally. Anisotropy of the local field and Lorentz-factor tensors has been found to decrease with the decreasing optical and molecular-optical anisotropies. These results appear to contradict the existing polarization theories of liquid crystals. The local field problem in cholesteric liquid crystals has been considered. A new approach to the local field problem in uniaxial liquid crystals with arbitrary optical anisotropy is developed and the experimental results are explained.     

A Modified Synthesis of 6-Aryl-3-(6-R-pyridin-2-yl)-1,2,4-triazines

Russian Journal of Organic Chemistry - A practical procedure has been proposed for the synthesis of 6-aryl-3-(pyridin-2-yl)-1,2,4-triazines containing various functional groups in the...     

Simple molecule-based fluorescent sensors for vapor detection of TNT

1,4-Diarylpentiptycenes (1a-e) were synthesized from 1,4-dichloro- or 1,4-difluoro-2,5-diarylbenzene derivatives by double base-promoted dehydrohalogenation to give corresponding arynes, which in the presence of anthracene undergo cycloaddition providing 1,4-diarylpentiptycenes in moderate overall yields. The resulting 1,4-diarylpentiptycenes show fluorescence modulated by the 1,4-aryl residues. The fluorescence is quenched in the presence of vapors of nitroaromatic compounds suggesting potential application in sensing of explosives.     

Reaction of 3-Amino-5H- and 3-Amino-5-sulfanyl-1,2,4-triazoles with 1,2,4-Triazine-5-carbonitriles

Russian Journal of Organic Chemistry - 1,2,4-Triazines with an unsubstituted (1,2,4-triazol-3-yl)amine residue in the C5 position were synthesized by the solvent-free ipso-amination reaction...