An engineered variant of subtilisin BPN', termed subtiligase, which efficiently ligates esterified peptides in aqueous solution, was used for the complete synthesis of ribonuclease (RNase) A that contains unnatural catalytic residues. Fully active RNase A (124 residues long) was produced in milligram quantities by stepwise ligation of six esterified peptide fragments (each 12 to 30 residues lon...

An efficient and facile method for the synthesis of substituted imidazoles (10a-10g) has been reported by reacting aldehydes (1–7), benzil (8) ammonium acetate [9] in presence reuseable solid acid catalyst viz. Rice Husk Ash.SO3H (RHA.SO3H) at room temperature. The homogeneity compounds was confirmed melting point thin layer chromatography. All synthesized were characterized 1H NMR FTIR spectra...

DURING A STUDY on the metabolism of histidine in a child affected with histidinemia (Beauvais, P., and Humbel, R., to be published), we became interested in the chromatography of imidazoles. In this disease the urine contains numerous imidazoles: histidine and its metabolites, imidazole-pyruvic, imidazole-lactic and imidazole-acetic acids and N-acetylhistidine.’I developed a chromatographic met...

Disubstituted imidazoles were prepared by reacting appropriate phenylglyoxal with different aryl aldehydes in the presence of ammonium acetate. Trisubstituted imidazoles were prepared by reacting disubstituted imidazoles with chlorobenzene in the presence of catalytic amount of triethylamine (TEA). The synthesized compounds were characterized on the basis of IR, 1H-NMR and mass spectral data an...

Systematically modified octyl galactosides and octyl N-acetyllactosamines were assessed as inhibitors of, and substrates for, T. cruzi trans-sialidase (TcTS) in the context of exploring its acceptor substrate binding site. These studies show that TcTS, which catalyses the α-(2→3)-sialylation of non-reducing terminal β-galactose residues, is largely intolerant of substitution of the galactose 2 ...

A diastereoselective and enantioselective construction of 2,3-disubstituted 1,4-dicarbonyl compounds is reported. Nishiyama's RuPhebox complex (2.0 mol% catalyst loading) serves as a chiral Lewis acid in conjunction with BrCCl3 base for the oxidative homocoupling 2-acyl imidazoles via stereocontrolled reaction intermediate Ru enolates situ brominated imidazoles. Cleavage achiral imidazole auxil...