The title compound {systematic name: (2S)-2-azaniumyl-3-[(2-carboxyethane)sulfonyl]propanoate}, C6H11NO6S, forms enantiopure crystals in the monoclinic space group P21 and exists as a zwitterion, with a protonated α-amino group and a deprotonated α-carboxyl group. Both the carboxyl groups and the amino group are involved in an extensive multicentered intermolecular hydrogen-bonding scheme. In the crystal, the diperiodic network of hydrogen bonds propagates parallel to (101) and involves interconnected heterodromic R43(10) rings. Electrostatic forces are major contributors to the structure energy, which was estimated by DFT calculations as Etotal = −333.5 kJ mol−1.
