US Patent 7232909 Pyridine derivatives

This invention is to provide a process for producing 2-amino-4,6-disubstituted nicotinic acid ester analogs and salts thereof, comprising the reaction shown by the following scheme. The ester analogs can be prepared in one pot, and in good yield by using tertiary alkyl cyanoacetate. Furthermore, the method is useful for preparing derivatives of various analogs of the ester, e.g. alkyl substituted and aryl substituted analogs.