NOPR Collection:

A new synthesis of azetidin-2-ones

2016-07-20T05:07:33Z

Title: A new synthesis of azetidin-2-ones Authors: Bari, S S; Sethi, M K; Sharma, Ashok K Abstract: Diphosphonium trifluoromethanesulfonate Ph₃P⁺-O-P⁺Ph₃.-2SO₃CF₃^- readily brings about direct annelation of imines to substituted azetidin-2-ones. Page(s): 1121-1122

Synthesis of purines and azapurines

2016-07-20T04:50:11Z

Title: Synthesis of purines and azapurines Authors: Shishoo, C J; Jain, K S; Jain, S R; Shirsath, V S; Ravikumar, T Abstract: The synthesis of a series of C₍₈₎ unsubstituled (11a-h), C₍₈₎ substituted (12a-e), 8-mercapto (13a-e) 1,3-diaryl-2- thioxanthines, as well as, 8-aza-1,3-diaryl-2-thioxanthines 14a-g, through precursors, 5,6-diamino-1,3-diaryl-2-thiouracils 10 has been reported. Recently, the synthesis of a novel series of 6-amino-1,3-diaryl-2-thiouracils 8 under the influence of dry HCI gas has been reported. ^14.15. These compounds are converted to the requisite 5,6-diamino-1,3-diaryl-2-thiouracils 10 via reduction of an intermediate 5-nitroso-6-amino-1,3-diaryl-2-thiouracils 9. Cyclocondensation of 5,6-diamino-2- thiouracils 10 with appropriate one carbon donors afford the desired purines 11-13. Page(s): 1052-1065

Anodically generated manganese (III) sulphate for the oxidation of aldo and keto hexoses: A kinetic and mechanistic study

2016-07-20T04:45:51Z

Title: Anodically generated manganese (III) sulphate for the oxidation of aldo and keto hexoses: A kinetic and mechanistic study Authors: Anitha, N; Rangappa, K S; Rai, K M Lokanatha Abstract: Kinetics of the oxidation D-glucose, D-fructose, D-mannose and L-sorbose by manganese (III) have been studied in the presence of sulphate ions in acidic medium at 32 °C. The reaction has been followed spectrophotome trically at λ_max = 500nm. A first order dependence of the rate on both Mn (III) and the hexose concentrations is observed. The rate is independent of the concentration of reduction product Mn(II) and hydrogen ions. Effects of varying dielectric constant of the medium and addition of anions such as sulphate, flouride, chloride and perchlorate have been investigated. Activation parameters have also been evaluated using Arrhenius and Eyring plots. A mechanism involving the formation of enediol from hexoses which reacts with Mn (III) in the rate limiting step is suggested. Page(s): 1046-1051

A simple method for the preparation of aryl phenacyl ether in micellar medium: Part I

2016-07-20T04:59:13Z

Title: A simple method for the preparation of aryl phenacyl ether in micellar medium: Part I Authors: Nallu, M; Selvakumar, Robinson; Pillay, M Krishna Abstract: Aryl phenacyl ethers have been prepared by the micellar catalysed reaction of phenacyl bromide with equimolar mixture of phenol(s)-triethylamine in 70% methanol(v/v) 30 °C. The ethers have been characterised on the basis of their IR, ¹H and ¹³C NMR spectral data. Page(s): 1108-1110