The present invention relates to a Xanthine derivative as shown in formula (I),wherein,R is selected from:R1 is selected from cyano or methoxycarbonyl；R2 is selected from hydrogen and halogen atoms, a linear or branched C1-6 alkyl group which is substituted or unsubstituted by 1 to 5 halogen atoms, a linear or branched C1-6 alkoxy group which is substituted or unsubstituted by 1 to 5 halogen atoms；X and Y are each independently selected from C or N； andn is 0, 1, 2, 3 or 4.
