Gemcitabine alpha-isomer conversion recovery process

The invention discloses a gemcitabine alpha-isomer conversion recovery process, which adopts a tetrabutylammonium hydroxide/ethanol system to convert a gemcitabine alpha-isomer into a gemcitabine beta-isomer. According to the present invention, systematic researches on an alkali type, a solvent system, a conversion temperature and the like are performed, the tetrabutylammonium hydroxide/ethanol system is screened, degradation is basically not generated during alpha-isomer conversion, the converted product has the same quality as the original product, the conversion yield can be more than 40%, and the new technology further provides important promotion significance for conversion recovery of other nucleoside drug isomers.