The invention provides a compound of formula (I): or a salt thereof, wherein R1-R4 have any of the values described in the specification, as well as compositions comprising a compound of formula (I). The compounds are useful as antibacterial agents.
The invention provides a compound of formula (I): or a salt thereof, wherein R
1
-R
4
have any of the values described in the specification, as well as compositions comprising a compound of formula (I). The compounds are useful as antibacterial agents.