5-[(3-Fluorophenyl)(2-hydroxy-6-oxocyclohex-1-en-1-yl)-methyl]-6-hydroxy-1,3-di-methylpyrimidine-2,4(1H,3H)-dione 3 was synthesized via a multicomponent reaction. The Aldol–Michael addition reactions of N,N-dimethylbarbituric acid, cyclohexane-1,3-dione, and 3-fluorobenzaldehyde in aqueous solution gave the product in high yield. The molecular structure of the compound was confirmed by spectroscopic methods and X-ray crystallography. The title compound (C19H19FN2O5·H2O) crystallizes in the Monoclinic form, P21/c, a = 7.8630 (5) Å, b = 20.0308 (13) Å, c = 11.3987 (8) Å, β = 104.274 (3)°, V = 1739.9 (2)° Å3, Z = 4, Rint = 0.117, wR(F2) = 0.124, T = 100 K.
