Crystals of sulfathiazole, 4-amino-N-thiazol-2-ylidene-benzenesulfonamide,
C9H9N3O2S2, formed from boiling water are shown to be a fifth polymorph. Th
e crystal structure contains two independent molecules, which associate thr
ough hydrogen bonds and van der Waals interactions to produce a two-dimensi
onal sheet structure.