The reaction of heteroaryl chlorides in the pyrimidine, pyrazine and quinazoline series with amines in water in the presence of KF results in a facile SN Ar reaction and N-arylation. The reaction is less satisfactory with pyridines unless an additional electron-withdrawing group is present. The results showed that the transition-metal-free SN Ar reaction not only compares favourably to palladiu...

A novel method for the preparation of hitherto unknown symmetrical bis(2-halo-3-pyridyl) dichalcogenides (E = S, Se and Te) by the oxidation of intermediate 2-halo-3-pyridyl chalcogenolate, prepared by lithiation of 2-halo pyridines using lithium diisopropylamine is being reported. All the newly synthesized compounds have been characterized through elemental analysis employing various spectrosc...

The catalytic C-H addition of pyridines to allenes has been achieved for the first time by using a half-sandwich scandium catalyst, thus constituting a straightforward and atom-economical route for the synthesis of alkenylated pyridine derivatives. The reaction proceeded regio- and stereoselectively, affording a new family of alkenylated pyridine compounds which are otherwise difficult to synth...

Ethyl pyruvate (EP) on reacting with malononitrile or isothiocyanates gives the pyridine derivati ves 5 and 9a , b , respecti vely. Chalcone deri vati ve of EP reacts with malononitrile to yield the pyran derivative which in turn IS transformed into pyridine derivative 14. Reactivity of 5 and 9a towards di fferent organic reagents has been investigated . Antimicrobial activity of some newly syn...

A series of simple 2-methylpyridines were synthesized in an expedited and convenient manner using a simplified bench-top continuous flow setup. The reactions proceeded with a high degree of selectivity, producing α-methylated pyridines in a much greener fashion than is possible using conventional batch reaction protocols. Eight 2-methylated pyridines were produced by progressing starting materi...

Abstract This thesis is concerned with the synthesis of -sultams and the development of new routes for the synthesis of bicyclic versions of these molecules as potential anti-bacterials. The synthesis of 1-azetines, 1,2-thiazetin-1,1-dioxides and isothiazol-1,1-dioxides as precursors of bicyclic heterocycles is described. 1-Azetines were synthesised from azetidin-2-ones prepared via the [2+2] c...

The structural resemblance between the fused imidazopyridine heterocyclic ring system and purines has prompted biological investigations to assess their potential therapeutic significance. They are known to play a crucial role in numerous disease conditions. The discovery of their first bioactivity as GABAA receptor positive allosteric modulators divulged their medicinal potential. Proton pump ...

Bacterial alkaline phosphatase is an active catalyst for the hydrolysis of N-phosphorylated pyridines, with values of the second-order rate constant kcat/Km in the range 0.4-1.2 x 10(6) M-1 s-1 at pH 8.0, 25 degrees C. There is little or no dependence of the rate on the pKa of the leaving group; the value of beta 1g is 0 +/- 0.05, which may be compared with beta 1g = -1.0 for the nonenzymic rea...

Asymmetric hydrogenation of (hetero)arenes is one of the most straightforward ways to synthesize enantiomerically pure, saturated or partially saturated cyclic molecules. Recent progress has significantly expanded the substrate scope of this reaction. Whereas a number of highly efficient catalytic systems have been found for the asymmetric hydrogenation of quinolines, structurally related isoqu...

The conditions of the reaction of malononitrile dimer with enaminones and arylidenemalononitrile could be adapted to yield either pyridines or benzene derivatives. A new synthesis of pyrido[1,2-a]pyrimidines from the reaction of malononitrile dimer 1 and 2-phenyl-3-piperidin-1-yl-acrylonitrile (11) is described. Compound 1 condensed with DMFDMA to yield an enaminonitrile that reacted with hydra...