The first method for the stereoconvergent cross-coupling of racemic α-halonitriles is described, specifically, nickel-catalyzed Negishi arylations and alkenylations that furnish an array of enantioenriched α-arylnitriles and allylic nitriles, respectively. Noteworthy features of this investigation include: the highly enantioselective synthesis of α-alkyl-α-aryl nitriles that bear secondary α-al...

From 2-aminonorbornene hydroxamic acids, a simple and efficient method for the preparation of pyrrolo[1,2-a]pyrimidine enantiomers is reported. The synthesis is based on domino ring-closure followed by microwave-induced retro Diels-Alder (RDA) protocols, where the chirality of the desired products is transferred from norbornene derivatives. The stereochemistry of the synthesized compounds was p...

The effect of alkyl group substituents on the degradation kinetics of poly(alkyl methacrylates) namely poly (n-butyl methacrylate) (PBMA), poly (iso-propyl methacrylate) (PPMA), poly (ethyl methacrylate) (PEMA), and poly (methyl methacrylate) (PMMA) in supercritical and subcritical conditions was studied at various temperatures (250 – 375 o C). The molecular weight distributions were measured b...

Streptomyces griseus var. alcalophilus was selected because it secreted a unique protease (protease I) that catalyzed the transfer reaction forming the hydroxamic acids of various amino acids. Protease I was purified to the electrophoretically homogeneous state and an activity of more than 125-fold that of the culture broth. The molecular weight of the enzyme was estimated to be 25,000 by gel f...

Iron added to a chemically defined liquid medium suppressed hydroxamic acid production at 37 degrees C by yeast cells of Histoplasma capsulatum. Four hydroxamic acids, HA-I, HA-II, HA-III, and HA-IV, present in the low-iron fluid after the culture of H. capsulatum were isolated by extraction and cation-exchange chromatography through cellulose phosphate (0.35% formic acid). Visible spectra of p...

Merkl R., Hrádková I., Filip V., Šmidrkal J. (2010): Antimicrobial and antioxidant properties of phenolic acids alkyl esters. Czech J. Food Sci., 28: 275–279. Some phenolic acids alkyl esters (methyl, ethyl, propyl, butyl and hexyl) and determine their antioxidant and antimicrobial activities were prepared. The antimicrobial activity against the tested microorganisms escherichia coli DMF 7503, ...

Interfacial molecular assemblies of eight atypical amphiphilic porphyrins, substituted with hydrophobic or hydrophilic substituents but without long alkyl chains on their molecular skeletons, have been investigated in terms of supramolecular chiralty generation and amplification. It is found that all of the originally organized interfacial molecular assemblies display very weak or undetectable ...

a simple, fast, efficient and environmentally friendly method for synthesis of benzimidazole and its 2-alkyl, aryl and heteroaryl substituted derivatives was developed using zeolite hy. two component cyclolcondensation of 1,2-phenylenediamine (o-phenylenediamine) and commercially available carboxylic acids catalyzed by zeolite hy without any solvent, under microwave irradiation led to formation...