226970-74-7 1H,6H-Pyrazolo[1,2-c][1,3,4]oxadiazine-7,8-dicarboxylic acid,tetrahydro-1-oxo-4,6-diphenyl-, dimethyl ester, (4R,6R,7S,8R)- 226970-92-9 1H,6H-Pyrazolo[1,2-c][1,3,4]oxadiazine-7-carboxylic acid,tetrahydro-1-oxo-4,6,8-triphenyl-, methyl ester, (4R,6R,7S,8S)-