Thiazolidone spiro pyrimidine trione compound, preparation method therefor and uses thereof

A compound represented by the general formula I, or an enantiomer, a diastereomer, a racemate and a mixture thereof, or a pharmaceutically acceptable salt thereof,

• wherein, R1 is hydrogen, halogen or cyano;
• R2 and R3 are each independently hydrogen, phenyl, substituted or unsubstituted C1-C6 alkyl, or ═CH2, and the term “substituted” refers to a substitution with a substituent selected from the group consisting of C1-C6 alkoxy, phenyl, halogen, —N3, —S(O2)C1-C6 alkyl, —NHCOC1-C6 alkyl, —CONHC1-C6 alkyl, —OR4, C1-C6 alkylthio, C2-C6 alkenyl, C2-C6 alkynyl;
• or R2, R3 and the attached carbon atoms together form a 4-7 membered aliphatic ring;
• R4 is hydrogen, or C1-C6 haloalkyl;
• * and ** each independently represent a racemic, S-type or R-type.