Maleanilic acid, p-methyl-

1-(p-tolyl)-3-(triphenyl-l⁵-phosphanylidene)pyrrolidine-2,5-dione

3-methylidene-1-(4-methylphenyl)pyrrolidine-2,5-dione

3-methyl-1-(4-methylphenyl)pyrrole-2,5-dione

2-hydroxy-2,3-dimethyl-succinic acid