In the title compound, C(11)H(12)N(2)O(3)·H(2)O, the water mol-ecule is a hydrogen-bond donor to the double-bond amide and the carbonyl O atoms of two acid mol-ecules; it is also a hydrogen-bond acceptor to the acid -OH and amide -NH- groups. These hydrogen-bonding inter-actions give rise to a layer structure, with the layers parallel to the ab plane.
* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.