PURPOSE: A gemcitabine prodrug is provided to ensure high bioavailability in gastrointestinal duct and to maintain same drug efficacy with gemcitabine. CONSTITUTION: A gemcitabine phosphoralkyl ester is denoted by chemical formula I. In chemical formula I, Z is -H or -C(O)-O-R； and W is -H and -C-O-C(O)-R". A method for preparing the gemcitabine phoaphoralkyl ester comprises: a step of reacting a compound of chemical formula II with trimethyl phosphate under the presence of phosphoryl(III) chloride(POCl3).본 발명은 젬시타빈 전구약물(gemcitabine prodrug) 및 이의 제조방법에 관한 것이다. 보다 상세하게는, 본 발명은 젬시타빈 전구약물로서 젬시타빈 포스포르알킬 에스테르(gemcitabine phosphoralkyl ester) 화합물 및 이의 제조방법에 관한 것이다.
