Glucuronide prodrugs of tofacitinib

A compound of formula I:

• wherein
• R1 is hydrogen or C1-3 alkyl;
• and
• A1 is selected from:
• (a) a group having formula (i):
• —[CH2]a—N(R2)C(O)— (i)
• wherein
• a is 2 or 3;
• and
• R2 is hydrogen or C1-3 alkyl;
• and
• (b) a group having formula (ii):
• wherein
• b is 0 or 1;
• c is 0 or 1;
• R3 is hydrogen or C1-3 alkyl;
• and
• B1 is selected from C6-10 aryl, C1-9 heteroaryl, C3-10 cycloalkyl and C2-9 heterocyclic;
• wherein the heteroaryl group contains from 1 to 4 heteroatoms selected from nitrogen, oxygen and sulfur;
• the aryl or heteroaryl group is unsubstituted or substituted with 1 to 3 substituents independently selected from C1-4 alkyl, C1-3 alkoxy, amino, cyano, halo, hydroxy, nitro and trifluoromethyl;
• the heterocyclic group contains from 1 to 3 heteroatoms selected from nitrogen, oxygen and sulfur;
• and the cycloalkyl or heterocyclic group is unsubstituted or substituted with 1 to 4 substituents independently selected from C1-4 alkyl, C1-3 alkoxy, hydroxy, and trifluoromethyl
• or a pharmaceutically-acceptable salt thereof.