A compound of formula I: or a pharmaceutically acceptable salt thereof, wherein: R 1 is a 5-6-membered aryl or heteroaryl group, optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, oxo, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl, C 1-6 alkylS 0-2 or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens; R 2 is a 5-6-membered aryl or heteroaryl group, optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl, C 1-6 alkylS 0-2 or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens; ring A represents a 5-6 membered aryl or heteroaryl group in which the carbon atom attached to the amide nitrogen atom contained in formula forms C=N together with the nitrogen atom in the ring, wherein ring A, in addition to the -L-T substituent, is further optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkylS 0-2, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen, C 1-6 alkyl or C 1-6 alkoxy where the alkyl and alkoxy substituents are optionally substituted by 1-6 halogens, L represents C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, NR 3 R 4, C 1-6 alkylNR 3 R 4, S 0-2 C 1-6 alkyl or S 0-2, wherein the alkyl and alkoxy groups are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens, T represents CO 2 R, CONR 3 R 4, or P (OR 5) 2, and R, R 3, R 4, and R 5 are individually selected from hydrogen or C 1-6 alkyl. R 1 is a 5-6-membered aryl or heteroaryl group, optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, oxo, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl, C 1-6 alkylS 0-2 or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens; R 2 is a 5-6-membered aryl or heteroaryl group, optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl, C 1-6 alkylS 0-2 or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens; ring A represents a 5-6 membered aryl or heteroaryl group in which the carbon atom attached to the amide nitrogen atom contained in formula forms C=N together with the nitrogen atom in the ring, wherein ring A, in addition to the -L-T substituent, is further optionally substituted with 1-4 substituents independently selected from: halogen, hydroxy, C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, C 1-6 alkylS 0-2, CN, NR 3 R 4, C 1-2 C 1-6 alkyl, C 1-6 alkylC 1-2 C 1-6 alkyl or S 0-2, wherein the alkyl and alkoxy substituents are further optionally substituted by 1-4 substituents independently selected from: halogen, C 1-6 alkyl or C 1-6 alkoxy where the alkyl and alkoxy substituents are optionally substituted by 1-6 halogens, L represents C 1-6 alkyl, C 1-6 alkylOC 1-6 alkyl, C 1-6 alkoxy, NR 3 R 4, C 1-6 alkylNR 3 R 4, S 0-2 C 1-6 alkyl or S 0-2, wherein the alkyl and alkoxy groups are further optionally substituted by 1-4 substituents independently selected from: halogen or C 1-6 alkyl where said C 1-6 alkyl is optionally substituted by 1-6 halogens, T represents CO 2 R, CONR 3 R 4, or P (OR 5) 2, and R, R 3, R 4, and R 5 are individually selected from hydrogen or C 1-6 alkyl.