Biocontrolled formal inversion or retention of L -α-amino acids to enantiopure (R)- or (S)-hydroxyacids
Natural L-α-amino acids and L-norleucine were transformed to the corresponding α-hydroxy acids by formal biocatalytic inversion or retention of absolute configuration. The one-pot transformation was achieved by a concurrent oxidation reduction cascade in aqueous media. A representative panel of enantiopure (R)- and (S)-2-hydroxy acids possessing aliphatic, aromatic and heteroaromatic moieties were isolated in high yield (67-85 %) and enantiopure form (>99 % ee) without requiring chromatographic purification.
Structure and enantioselective synthesis of polyamine toxin MG30 from the venom of the spider Macrothele gigas
A novel polyamine toxin, named MG30, was isolated from the venom of the spider, Macrothele gigas, and its structure was elucidated by two-dimensional NMR and mass analysis. In addition, the enantioselective synthesis of MG30 was achieved to assign its absolute stereochemistry.
Formations of (5-Hydroxy)indole S-(-)-lactic Acid, N-acetyl-5-hydroxy-L-tryptophan and (5-Hydroxy)indole Carboxylic Acid in the Metabolism of Tryptophan and 5-Hydroxytryptophan by Chromobacterium violaceum
Tryptophan metabolism catalyzing the production of (5-hydroxy)indolelactate, (5-hydroxy)indole carboxylate, and N-acetyl-5-hydroxytryptophan was found in Chromobacterium violaceum.These metabolites have never been reported before.Metabolic pathways from tryptophan and 5-hydroxytryptophan are proposed.