Stereoselective total synthesis of (+)-polyoxin J is described. The synthesis was achieved in aconvergent manner by coupling protected thymine polyoxin C (19) and 5-O-carbamoyl polyoxamicacid 27 and subsequent removal of the protecting groups. The key steps of the synthesis of protectedthymine polyoxin C involved the stereoselective electrophilic epoxidation of E-allyl alcohol 7 derivedfrom isopropylidene d-ribose derivative 5, followed by regioselective epoxide opening of 8 andconversion of resulting azido diol 9 to protected thymine polyoxin C (19). Protected polyoxamicacid 27 was synthesized stereoselectively by utilizing Sharpless epoxidation of tartrate-derivedallylic alcohol 20 followed by a regioselective epoxide ring opening with diisopropoxytitanium diazide.