It is well known that o-hydroxy aromatic aldehydes* will condense with acetone and other ketones to form compounds structurally related to the anthocyanidins and to the dicoumarins. It was s~ ggested~ J*~ that the mechanism of the condensation involves, in the case of equimolar proportions of acetone and salicylaldehyde, an unsaturated intermediate, ziz., o-hydroxystyryl methyl ketone. The condensation of salicylaldehyde and various ...