Stereoselective enzymatic synthesis of monoglucosyl-myo-inositols with in vivo anti-inflammatory activity
摘要:
The monoglucosyl-inositols alpha-D-glucopyranosyl-(1 -> 4)-4D-myo-inositol 3 and alpha-D-glucopyranosyl-(1 -> 1)-1D-myo-inositol 4 were synthesized by a combined enzymatic transglucosylation and hydrolysis strategy, using cyclodextrin glucosyl transferase (CGTase) from Thermoanaerobacter sp, followed by hydrolysis with Aspergillus niger glucoamylase The glucosides were separated by preparative HPLC and fully characterized by extensive 1D and 2D NMR studies. The structure of the regioisomer 4 was confirmed by X-ray crystallography of its perbenzoylated derivative 4a Both isomers demonstrated in vivo anti-inflammatory activity at comparative levels to corticosterone on mouse ear oedema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) and in rat hind paw oedema Induced by carrageenan (c) 2009 Elsevier Ltd All rights reserved
Regioselective glucosylation of inositols catalyzed by Thermoanaerobacter sp. CGTase
摘要:
Monoglucosylated products of L-chiro-, D-chiro-, muco-, and allo-inositol were synthesized by regioselective alpha-D-glucosylation with cyclodextrin glucosyl transferase from Thermoanaerobacter sp. after hydrolysis of by products with Aspergillus niger glucoamylase. While the reactions carried out with D-chiro-, muco-, and allo-inositol resulted in the regioselective formation of monoglucosylated products, two products were obtained in the reaction with L-chiro-inositol. Through the structural characterization of the glucosylated inositols here we demonstrated that the selectivity observed in the glucosylation of several inositols by Thermoanaerobacter sp. CGTase, is analogous to the specificity observed for the glucosylation of beta-D-glucopyranose and equivalent glucosides. (C) 2012 Elsevier Ltd. All rights reserved.