A versatile and convenient route to ketone C-pyranosides and ketone C-furanosides from unprotected sugars
作者:Junfeng Wang、Qin Li、Zemei Ge、Runtao Li
DOI:10.1016/j.tet.2011.11.029
日期:2012.1
Both ketone C-pyranosides (in up to 97% yields) and C-furanosides (in 83–97% yields) could be prepared, respectively, from the condensations of pentane-2,4-dione and various unprotected sugars in sodium carbonate aqueous media by adjusting the reaction conditions.
The synthesis of C-glycosides in water or in the absence of any solvent from free sugars and β-keto phosphonates is reported. The methodology permits a one-step access to C-glycoside amphiphiles in moderate-to-good yields. The selectivity (α/β and furanoside/pyranoside) is discussed and a process that leads to pure β-C-pyranosides is also described.