Furan ring lactone derivatives and their use

The present invention provides a compound of formula I, or a pharmaceutically acceptable salt thereof as or prodrug thereof, R1, R3 are independently selected from H, C 1-4 alkyl, 1 to 3 halogen; R2 is selected from H, phenyl or substituted phenyl, the substituent is halo or C1-4 alkyl; wherein, when R2 is phenyl, R1, and R3 are not both H; or, when R2 is H, R1, and R3 are not simultaneously halogen. The present invention further provides a use thereof. The present invention provides a compound having antibacterial activities, it can be used as potential antibacterial medicament, provide a new choice for clinical medication.