Substituted benzopyranopyridopyrimidine ring syntheses by the ternary condensation of malononitrile, salicylaldehyde, and aromatic ketones in the presence of ammonium acetate
Substituted benzopyranopyridopyrimidine ring syntheses by the ternary condensation of malononitrile, salicylaldehyde, and aromatic ketones in the presence of ammonium acetate