دانلود رایگان مقاله گلیکوزیلاسیون رجیوسلکتیو هیدروکسیل الکلی واسطه شده زیست دگرگونی قارچی

Abstract

An efficient glucosylation of alcoholic hydroxyls in the structures of protostane triterpenoids catalyzed by fungus has been developed. Four protostanes 1–4 as the substrates have been transformed by Syncephalastrum racemosum AS 3.264 and generated corresponding 11-OH glucosylation derivatives. The regioselective characteristics were also identified by various highly oxygenated protostane substrates. The time-courses displayed the highest yields of 1a, 3a, and 4a at > 50%, and 1a had the highest yield of 72%. All of the protostane analogues displayed hCE-2 inhibitory effects in an in vitro bioassay. This report describes a rare biocatalytic alcoholic hydroxyl glucosylation with considerable yield and regioselective characteristics.

4. Conclusions

We have report a novel glucosylation method of alcoholic hydroxyls in protostane triterpenoids, which are important bioactive natural products. The glucosylation was catalyzed by S. racemosum AS 3.264 with signifi- cant highly efficient and regioseletive characteristics. For the transformation of four major protostanes, there were only 11-OH glucosylated derivatives presenting the highest yield of 72%. The authors believe that this fungus and even the GTs of this fungus could be developed to be an important method for the glucosylation of alcoholic hydroxyls.