Organic Communications Articles

The asymmetric hydrogenation of methyl acetoacetate was successfully performed with baker's yeast in pure glycerol and mixtures of glycerol and water. Though yeast viability was very low after exposure to glycerol, the enzymatic activity in pure glycerol was preserved for some days. In addition, a mixture of glycerol and water combined the advantageous of each individual solvent and resulted in high catalytic performance and efficient product extraction yield.

The synthesis of four new peptidyl nucleosides is reported. The kinetic data obtained for the transesterification of 2'/3'-O-benzyloxycarbonyl-L-p-nitrophenylalanyl 5'-O-trityl ribonucleosides which contain different substituents at C 6 position of the purine residue indicates for different mechanisms of the transesterification reaction. The peptidyl nucleosides with an amino group at C 6 position and those lacking such group at that position have two distinctive mechanisms of transesterification.

In the present study a series of urea inclusion complexes (1-30) were synthesized and evaluated for their in vitro antibacterial activity against Gram positive Staphylococcus aureus, Bacillus subtilis, Gram negative Escherichia coli and antifungal activity against Candida albicans and Aspergillus niger . The most of the synthesized complexes have shown moderate antimicrobial activity. The urea inclusion complexes of capric acid, pamoic acid and 3-hydroxybenzoic acid were found to be the most active ones.

Application of stable hydrochloride salt of 1-chlorocarbonyl-4-methylpiperzine 2 and tetrabutyl ammonium bromide (TBAB) as a phase transfer catalyst in an improved process of eszopiclone 1 is presented.