N,N-dimethylformamide-promoted reaction of isocyanides and barbituric acids: an easy synthesis of 5-[(alkyl or arylamino)methylene]barbituric acids

N,N-dimethylformamide promoted the reaction of alkyl or arylisocyanides with barbituric acid derivatives which led to 5-[(alkyl or arylamino) methylene]barbituric acids in good yields at room temperature. The work-up of reactions was very simple and the crude products were sufficiently pure to be used without further purification. This procedure provides an alternative method for the synthesis of aminomethylenebarbituric acids.