Electrospray ionisation mass spectrometry shows that arylstibonic acids, RSbO(3)H(2), give rise to oxo-bridged clusters derived from [H(8)(RSb)(12)O(28)] which act as inorganic crown ligands towards Na(+) cations; structure determination of one derivative revealed a cage-like anion [Na(2)H(9)(p-O(2)NC(6)H(4)Sb)(12)O(30).4H(2)O](-).

Carboxhydrazides 3 were synthesized by reaction of substituted furo[3,2-b]pyrrole-5-carboxhydrazides 1 with 4-oxo-4H-chromene-2-carboxaldehyde 2 in the presence of 3-methyl-benzenesulfonic acid in ethanol. Carboxhydrazides 3 were used as ligands for synthesis of Cu, Co, and Ni complexes 4.

A catalytic amount of tin(IV) chloride catalyzed formal [4+2] cycloaddition reaction of di-tert-butyl 2-ethoxycyclobutane-1,1-carboxylate with ketones or aldehydes to give diethyl 6-ethoxydihydro-2H-pyran-3,3(4H)-dicarboxylates, whereas two equivalents of trimethylsilyl triflate promoted tandem [4+2] cycloaddition and lactonization to afford 3-oxo-2,6-dioxabicyclo[2.2.2]octane-4-carboxylate est...

A new, simple thermally efficient and solvent-free condensation of 2-amino-3-cyano-6-methyl-4-phenyl-4H-pyran-5-ethylcarboxylate derivatives with coumarin-3-carboxylic acid employing pentafluorophenylammonium triflate (PFPAT) as an inexpensive organocatalyst for the synthesis of a series of ethyl 4,5-dihydro 7-methyl-2-(2-oxo-2H-chromen-3-yl)-4-oxo-5-aryl-3H-chromeno[2,3-d]pyrimidine-6-carboxyl...

Some new nitrogen bridge-head pyrido[1,2-b][1,2,4]triazepines incorporating 6methylchromone moiety have been synthesized from the reaction of 1,6-diamino-4-(6methyl-4-oxo-4H-chromen-3-yl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4) with some α,γ-bifunctional electrophiles including 2-cyano-3,3-bis(methylthio)acrylonitrile, 2cyano-3,3-bis(methylthio)prop-2-enamide, 5-chloro-3-methyl-1-pheny...

A series of S-glycosyl and S-alkyl derivatives of 4-amino-3-mercapto-6-(2-(2-thienyl)vinyl)-1,2,4-triazin-5(4H)-one (1) were synthesized using different halo compounds such as preacetylated sugar bromide, 4-bromobutylacetate, 2-acetoxyethoxy-methyl bromide, 3-chloropropanol, 1,3-dichloro-2-propanol, epichlorohydrin, allyl bromide, propargyl bromide, phthalic and succinic acids in POCl3. The str...

Predictive quantitative structure–activity relationship was performed on the novel 4-oxo-1,4-dihydroquinoline and 4-oxo-4H-pyrido[1,2-a]pyrimidine derivatives to explore relationship between the structure of synthesized compounds and their anti-HIV-1 activities. In this way, the suitable set of the molecular descriptors was calculated and the important descriptors using the variable selections ...

A convenient method for the synthesis of 2-(2-R-5-oxo-6,7-dihydro-4H-[1,2,4]triazolo-[1,5-a]pyrimidin-6-yl)acetanilides based on regioselective domino reaction N-arylitaconimides with substituted 3-aminotriazoles was proposed. Presumably, pathway includes conjugated aza-addition endo-nucleophilic center triazole to imide, followed by recyclization intermediate triazolo[1,5-a]pyrimidine.