Antibiotic conjugates

A compound of formula (I):

• or a pharmaceutically acceptable salt thereof, wherein
• Sid is a siderophore moiety selected from the group consisting of
• L is a bond, —C(O)—, —C(O)NHCH(R1)—C(O)—, —C(O)OCH(R2)—C(O)—, or
• R1 and R2 are each hydrogen, C1-6alkyl, cyano, C3-6cycloalkyl, C3-6cycloalkenyl, 6- to 12-membered aryl, or 5- to 12-membered heteroaryl, wherein the C3-6cycloalkyl, C3-6cycloalkenyl, 6- to 12-membered aryl, or 5- to 12-membered heteroaryl is optionally substituted with 1-5 substituents independently selected from the group consisting of halogen, C1-4alkyl, C1-4 haloalkyl, —OC1-4alkyl, —OC1-4haloalkyl, OH, oxo, and cyano;
• R3 and R4 are each independently hydrogen, C1-6alkyl, or Rand R4 together with the C atom to which they are attached form a 3- to 8-membered ring;
• Cyc1 is a 6- to 12-membered aryl or 5- to 12-membered heteroaryl, wherein the 6- to 12-membered aryl or 5- to 12-membered heteroaryl is optionally substituted with 1-5 substituents independently selected from the group consisting of halogen, C1-4alkyl, C1-4haloalkyl, —OC1-4alkyl, —OC1-4haloalkyl, OH, oxo, and cyano;
• Y is O or NH;
• G is -G1 or —X—(CH2)pC(O)-G1;
• X is O or S;
• p is 0, 1, 2, 3, 4, or 5;
• and
• G1 is a drug moiety attached through an oxygen or nitrogen atom,
• a wherein G1 is an oxazolidinone antibiotic.