2-Aminoquinolin-4(1H)-one was reacted with various primary/secondary amines and paraformaldehyde under Mannich reaction conditions. In the case of secondary amines, the reaction in N,N-dimethylformamide yielded expected Mannich products accompanied with 3,3'-methylenebis(2-aminoquinolin-4(1H)-one). Except these main products, the pyrimido[4,5-b]quinolin-5-one derivative was also identified as c...

Abstract- Some new 3-(alkylsulfanyl)- 7-chloro-1-phenyl-1H-pyridazino [4,3-e][1,3,4]thiadiazine were synthesized  by treatment of the alkyl-2-phenylhydrazinecarbodithioates with 4-bromo-3,6-dichloropyridazine in alkaline acetonitril. Orientation of the reaction has been determined by X-Ray crystallography technique. The chlorine atom on the number 7 position of these products was repla...

The Eschenmoser coupling is a useful carbon-carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yie...

Examining a sample of 701 offshore securities offerings under Regulation S of the Securities Act from 1993 to 1997, this Article tests whether foreign investors expect to resell Regulation S securities in the United States ahead of the U.S. secondary market reaction to news of the offering. The Article provides evidence from an event study that the secondary market reaction to a Regulation S of...

A new synthetic route for binaphthyl-based secondary amines has been developed. The key features of this route include the selective direct esterification of the binaphthyl structure at the 3- or 3,3'-position and the methylation by a Negishi cross-coupling reaction. Based on the new approach, a series of 3-monosubstituted and 3,3'-disubstituted chiral secondary amines with a binaphthyl backbon...

We report 11 μs of molecular dynamics simulations of the electron-transfer reaction between primary and secondary quinone cofactors in the bacterial reaction center. The main question addressed here is the mechanistic reason for unidirectional electron transfer between chemically identical cofactors. We find that electron is trapped at the secondary quinone by wetting of the protein pocket foll...

Following an optimized multicomponent procedure, an aryl amine, a ketone, and a cyclic ether or an alcohol molecule are assembled in a one-pot synthesis by nucleophilic radical addition of ketyl radicals to ketimines generated in situ. The reaction occurs under mild conditions by mediation of the TiCl4/Zn/t-BuOOH system, leading to the formation of quaternary β-amino-ethers and -alcohols. The n...

an efficient method is described for the mild and rapid tetrahydropyranylation of alcohols and phenols using a catalytic amount of n-chlorosaccharin (1 mol %) and 3, 4-dihydro-2h-pyran under solvent-free condition at room temperature. benzylic alcohols and phenols containing electron withdrawing or donating groups in various positions of phenyl ring, cinamyl alcohol, primary, secondary, tertiar...

Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl]ester (SASPSPE) is employed as a recyclable catalyst for the silylation of hydroxyl groups. A good range of primary, secondary alcohols and phenolic hydroxyl groups were effectively converted into their corresponding trimethylsilyl ethers with hexamethyldisilazane in the presence of catalytic amounts of SASPSPE at room temperature with short rea...