SYNTHESIS AND PROPERTIES OF 2-AMINO-4,6-DIMETHYLNICOTINIC ACID ARYLAMIDES

Article abstract of DOI:10.1007/BF00529583

It is shown that on boiling 2-amino-4,6-dimethylnicotinic acid arylamides with triethyl orthoformate in acetic anhydride, derivatives of 3-aryl-5,7-dimethyl-4-oxo-3,4-dihydropyrido<2,3-d>pyrimidine are formed.The same compounds are obtained by ternary condensation of ethyl 2-amino-4,6-dimethylnicotinate with triethyl orthoformate and arylamines.On reaction with urea or ammonium thiocyanate, the ethyl ester or anilides of 2-amino-4,6-dimethylnicothinic acid are converted to 2,4-dioxo- or 4-oxo-2-thio-pyrido<2,3-d>pyrimidines respectively.