1,3-Bis(3-fluoro-4-morpholinophenyl)urea is an impurity in the synthesis of (3-Fluoro-4-morpholin-4-ylphenyl)carbamic Acid Methyl Ester (F498590), an impurity of Linezolid (L466500). Linezolid is a prototype of the oxazolidinone antimicrobials; inhibits bacterial mRNA translation.