Cytochrome P450 2A13-catalyzed alpha-hydroxylation is a critical step in the activation of the tobacco carcinogens 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and (S)-N'-nitrosonornicotine [(S)-NNN]. In the enzyme's active site, a single polar residue, Asn297, can influence substrate binding, orientation, and metabolism. We determined the effects of N297A mutation on enzyme kinetics an...

A reinvestigation of a chiral phosphoric-acid-catalyzed four-component Hantzsch enantioselective synthesis polyhydroquinolines reported in 2009 is presented. In our hands, when the reaction was performed with fidelity to original report using enantiopure phosphoric acid catalyst, no enantioselectivity observed. Unlike report, results are backed by baseline separation enantiomers HPLC analyses o...

a two-dimensional nanolayered polyoxomolybdate, [4,4´-h2bipy] [mo7o22].h2o (1), where 4,4´-bipy = 4,4´-bipyridine, was prepared and characterized by ft-ir and atomic absorption spectroscopies, transmission electron microscopy (tem), x-ray single crystal and powder diffraction (xrd), and thermogravimetric analysis. the catalytic performance of 1 was assessed in the epoxidation of some olefins em...

Here, we focused on a simple enzymatic epoxidation of alkenes using lipase and phenylacetic acid. The immobilised Candida antarctica lipase B, Novozym 435 was used to catalyse the formation of peroxy acid instantly from hydrogen peroxide (H2O2) and phenylacetic acid. The peroxy phenylacetic acid generated was then utilised directly for in situ oxidation of alkenes. A variety of alkenes were oxi...

The C8'-epimeric pyranosyl amino acid core 2 of amipurimycin was synthesized from D-glucose derived alcohol 3 in 13 steps and 14% overall yield. Thus, the Sharpless asymmetric epoxidation of allyl alcohol 7 followed by trimethyl borate mediated regio-selective oxirane ring opening with azide, afforded azido diol 10. The acid-catalyzed 1,2-acetonide ring opening in 10 concomitantly led to the fo...

Epoxidized vegetable oils are the product of vegetable oil epoxidation reactions. Since the epoxidized vegetable oil is a nonpoisonous plasticizer, it has been wildly used in the plastic packaging of food and medicine. Among the various epoxidized vegetable oils, the application of epoxidized soybean oil is broader than others. Nowadays, it’s the third largest category of plasticizers. However,...

BACKGROUND Contamination of agricultural commodities with multiple trichothecene mycotoxins, produced by toxigenic Fusarium species, is a food safety issue, which greatly affects grain production and marketing worldwide. Importantly, exposure to multiple trichothecenes may increase toxicity in animals due to their synergistic and/or additive effects. To address the problem this study aimed to a...

The oxidation of C-H, C-C and C=C of hydrocarbons, from the syntheses of many fine chemicals to the manufacture of various commodities in large scale, plays great important role in transformation of basic materials to useful synthetic building in organic chemistry and in conversion of hydrocarbon to oxygen-containing industrial production especially the hydroxylation, epoxidation, degradation o...

An efficient one pot multi component synthesis of 1, 4-Polyhydroquinoline derivatives through unsymmetrical Hantzsch reaction using lanthanum chloride heptahydrate (LaCl3.7H2O) from an aromatic aldehyde, ethyl acetoacetate, dimedone and ammonium acetate as a nitrogen precursor in ethanol at room temperature is described. In the present work we report lanthanum chloride heptahydrate remarkably n...