A compound having the structure set forth in Formula (I) and Formula (II): wherein the substituents Y, Z, A, B, R1, R2, R3, R4 and R5 are as defined herein. Provided herein are inhibitors of poly(ADP-ribose)polymerase activity. Also described herein are pharmaceutical compositions that include at least one compound described herein and the use of a compound or pharmaceutical composition described herein to treat diseases, disorders and conditions that are ameliorated by the inhibition of PARP activity.