Convenient Synthesis of the Antibiotic Linezolid via an Oxazolidine-2,4-dione Intermediate Derived from the Chiral Building Block Isoserine

We describe a new synthesis of the 5-(aminomethyl)oxazolidin-3-one core of linezolid in enantiomerically pure form. The expedient cyclization of the α-hydroxy amide derived from isoserine and 3-fluoro-4-morpholinoaniline to give the corresponding (aminomethyl)oxazolidine-2,4-dione, followed by its mild selective reduction at the C(4)-position, gave linezolid in almost quantitative overall yield.