0-26-00-00410 (Beilstein Handbook Reference) 4-Methyl-5-phenyl-6-oxo-(4H)pyrazolo(3,4-d)pyrazole 99640-28-5 BRN 0020178 Pyrazolo(4,3-c)pyrazol-3(2H)-one, 1,4-dihydro-1-methyl-2-phenyl-