(2R)-2-(1,3-Dioxoisoindolin-2-yl)-3-methyl­butanoic acid

In the title compound, C13H13NO4, the dihedral angle between the nine-membered phthalimino ring system and the carb­oxy­lic acid group is 67.15 (9)°. An intra­molecular C—H⋯O close contact, which forms an S(6) ring, may help to establish the mol­ecular conformation. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, thereby forming C(7) chains propagating in [010]

2-(2-Oxothio­lan-3-yl)isoindoline-1,3-dione

In the title compound, C12H9NO3S, the isoindoline-1,3-dione group is almost planar, with an r.m.s. deviation of 0.020 Å, whereas the heterocyclic ring approximates to an envelope with the methyl­ene group not adjacent to the S atom in the flap position. A short intra­molecular C—H⋯O contact generates an S(6) ring motif. In the crystal structure, weak aromatic π–π stacking inter­actions occur between the centroids of the benzene rings at a distance of 3.558 (2) Å