COMe, Y' = CO(2)Et (10 and 11) enolization in solution and of 11 also in the solid state occurs at the carbonyl rather than at the ester site. With Y = Y' = CN a rapid exchange between the amide (NC)(2)CHCONHPh (12a) and a tautomer, presumably the enol, take place in several solvents on the NMR time scale. With YY' = barbituric acid moiety the species in DMSO-d(6) is an enol of an amide although which