The structure of ammocidin, a new apoptosis inducer in Ras-dependent cells from Saccharothnx sp. AJ9571, was elucidated to be as shown in Fig. 1 by NMR and degradation studies. Ammocidin consists of a 20-membered macrolide ring and three deoxy sugars identified as 6-deoxy-L-glucose, D-digitoxose and D-olivomycose.
Catalytic and Regioselective Oxidation of Carbohydrates To Synthesize Keto-Sugars under Mild Conditions
作者:Wataru Muramatsu
DOI:10.1021/ol502344h
日期:2014.9.19
A new catalytic and regioselective approach for the synthesis of keto-sugars is described. An organotin catalyst, Oc2SnCl2, in the presence of trimethylphenylammonium tribromide ([TMPhA](+)Br3(-)) accelerates the regioselective oxidation at the "axial"-OH group of 1,2-diol moieties in galactopyranosides. The reaction conditions can also be used for the regioselective oxidation of various carbohydrates.