Abstract: The invention provides a compound of formula (0): or a pharmaceutically acceptable salt, N-oxide or tautomer thereof; wherein: n is 1 or 2; X is CH or N; Y is selected from CH and C—F; Z is selected from C—Rz and N; R1 is selected from: -(Alk1)t-Cyc1; wherein t is 0 or 1; Optionally substituted C1-6 acyclic hydrocarbon groups R2 is selected from hydrogen; halogen; and C1-3 hydrocarbon groups optionally substituted with one or more fluorine atoms; R3 is hydrogen or a group L1-R7; R4 is selected from hydrogen; methoxy; and optionally substituted C1-3 alkyl; and R4a is selected from hydrogen and a C1-3 alkyl group; wherein Rz, Alk1, Cyc1, L1 and R7 are defined herein; provided that the compound is other than 6-benzyl-3-{2-[(2-methylpyrimidin-4-yl)amino]pyridin-4-yl}-7,8-dihydro-1,6-naphthyridin-5(6H)-one and 3-{2-[(2-methylpyrimidin-4-yl)amino]pyridin-4-yl}-7,8-dihydro-1,6-naphthyridin-5(6H)-one and salts and tautomers thereof.

Abstract: Certain multi-cyclic compounds and compositions thereof are useful for reducing or inhibiting the growth of bacterial biofilms and for controlling bacterial biofilm infections. Such compounds and compositions are also useful in methods for reducing or inhibiting the growth of biofilms and for controlling bacterial biofilm infections involving biofilms.