c - aryl glucoside derivatives , preparation methods thereof , and medical applications thereof are described . specifically , compounds represented by formula i , and , tautomers , enantiomers , diastereomers , racemates , and pharmaceutically acceptable salts of the compounds , preparation methods thereof , pharmaceutical compositions containing the compounds , and applications thereof are described . compounds of formula are useful as therapeutic agents , and particularly as sodium - dependent glucose contransporter protein inhibitors .