A compound of the formula: wherein X is &mdash；N&boxH；, &mdash；CH&boxH；, or the like； W is &mdash；CH2&mdash； or the like； U is &mdash；S&mdash； or the like； R1 and R2 are each independently hydrogen, halogen, optionally substituted lower alkyl, or the like； Q is a single bond or the like； R3 is hydrogen or the like； Ring A is a 6-membered aromatic heterocyclic group having 1-3 nitrogen atoms； each R4 is independently hydrogen, halogen, or the like； m is an integer from 0 to 2； G is &mdash；C(&boxH；O)&mdash； or the like； D is a single bond, &mdash；NH&mdash；, or the like； and E is a cyclic quaternary ammonium group, or an ester, a protected compound at the amino on the ring in the 7-side chain, a pharmaceutically acceptable salt, or a solvate thereof.
