4-Octulose Derivatives, Prepared fromL-Sorbose, as Key Intermediates in the Stereoselective Synthesis ofC-Glycoside and Polyhydroxyindolizidine Analogues
作者:Isidoro Izquierdo、Maria T. Plaza、Rafael Robles、Antonio J. Mota
unsuccessful and an internal anhydration process took place to yield the corresponding C-glycoside-like furanoses 9 and 20. On the other hand, 23 was transformed into the D-ribo analogue 25 through reduction of the intermediate 4,6-diulose 24. Finally, deprotection of 25 in acid medium to give the free 4-ulose 26, followed by hydrogenation of the latter in the presence of 10% Pd/C in methanol, allowed