Mannich reaction of 3-hydroxycoumarin and 5,7-dihydroxy-4-methylcoumarin with secondary amines and 1-arylpiperazines

The reaction of 3-hydroxycouniarin with 1-arylpiperazines and paraformaldehyde gives the corresponding 4-pipcrazinylmethyl derivatives. The reaction of 5,7-dihydroxy-4-niethylcoumarin with secondary amines/1-arylpiparazines and paraformaldehyde gives the corresponding 6,8-bisaminomethyl derivatives.