A new efficient synthesis of 5-aryloxazoles from arylidene diacetates and application to the preparation of BMS-337197, a novel impdh inhibitor

A new method for the synthesis of 5-aryloxazoles is described. Treatment of arylidene diacetates with one equivalent of TosMIC reagent in the presence of excess of potassium carbonate in methanol afforded 5-aryloxazoles in "one-pot" in 90-94%. Heteroarylidene diacetates reacted in a similar way. Application of the new method to the synthesis of the novel IMPDH inhibitor BMS-337197 is also presented.