title: 3-Carbamoyl-2,2-dimethyl-cyclo-pentane-1,1-dicarb-oxy-lic acid.
abstract: In the title compound, C(10)H(15)NO(5), the five-membered cyclo-pentane ring has an envelope conformation, with four atoms lying in a plane (mean deviation = 0.0213 Å), while the fifth atom deviates from this plane by 0.626 (2) Å. A three-dimensional structure is formed through N-H⋯O and O-H⋯O hydrogen bonds between the amide and carb-oxy-lic acid groups and both carb-oxy-lic acid and amide O-atom acceptors.
authors.affiliation: National Taras Shevchenko University, Department of Chemistry, Volodymyrska Street 64, 01033 Kyiv,  Ukraine.
authors.forename: Volodymyr
authors.initials: V
authors.lastname: Knizhnikov
authors.forename: Marian
authors.initials: M
authors.lastname: Gorichko
authors.forename: Zoya
authors.initials: Z
authors.lastname: Voitenko