Abstract: The present invention provides compounds of formula I: formula (I) wherein X1-X4 and R1-R12 have any of the values defined in the specification, as well as salts and prodrugs thereof, which inhibit major molecular mechanisms associated with bacterial cell division and proliferation so as to be useful for the treatment and/or prevention of bacterial infections. The invention also provides compositions comprising these compounds as well as methods for using these compounds to inhibit bacterial cell division and proliferation and to treat bacterial infections.