Synthesis of 3-(2-Hydroxyaryl)-1-methyl-2-pyrazolin-5-ones from 4-Hydroxycoumarins and their Conversion to 2-Methyl-1-benzopyrano[4,3-c]pyrazol-3(2H)-one Derivatives
Synthesis of 3-(2-Hydroxyaryl)-1-methyl-2-pyrazolin-5-ones from 4-Hydroxycoumarins and their Conversion to 2-Methyl-1-benzopyrano[4,3-c]pyrazol-3(2H)-one Derivatives