Synonyms: 1,3-Propanediaminecyclic urea;2-Ketohexahydropyrimidine;3,4,5,6-Tetrahydropyrimidin-2(1H)-one;Hexahydro-1H-pyrimidin-2-one;N,N'-Trimethyleneurea;NSC 21315;Propyleneurea;Tetrahydro-2(1H)-pyrimidinone;Tetrahydro-2-pyrimidinone;Tetrahydro-2-pyrimidone;Urea, N,N'-1,3-propanediyl-;