Synthesis of 3-methyl-5-methoxy-6-hydroxy-7-acetyl-coumaronic and 3,7-dimethyl-5-methoxy-9-H-furo [2,3-f] [1] benzopyran-9-on-2-carboxylic acids and their derivatives.

New 3-methyl-5-methoxy-6-hydroxy-7-acetylcoumaronic acid and several its esters with aminoalcohols have been obtained. By the condensation of this compound with ethyl acetate and sodium 3,7-dimethyl-5-methoxy-9-H-furo [2, 3-f] [1] benzopyran--on-2-carboxylic acid was obtained. Aminoesters of this acid show a weak hypotensive activity.