Analogs of 2- (4-heterociclilbencil) isoindolin-1-one compounds as positive allosteric modulators of muscarinic acetylcholine receptor M1

A compound having a structure represented by the formula: ** ** Formula or where each of R1a, R1b, R1c, R1d and, when present, is independently selected from hydrogen, halogen, C1-C6 alkyl, haloalkyl C1- C6, polyhaloalkyl C1-C6 alkyl, C1-C6 alkyl, C1-C6-C1-C6 alkyl, C1-C6 alkylamino, C1-C6-oxy-C1-C6 alkyl, polyhaloC C1-C6-oxy-C1-C6 and dialkylamino C1-C6 alkyl; where each of R2a, R2b, R2c, and R2d, when present, is independently selected from hydrogen, halogen, C1-C6 alkyl, C1-C6 haloalkyl, polyhaloalkyl C1-C6alkyl, C1-C6alkyl, C1-C6- C1-C6 alkyl, C1-C6 alkylamino, C1-C6-oxy-C1-C6 alkyl, C1-C6 polyhaloalkyl-oxy-C1-C6, and C1-C6 dialkylamino; wherein each of R5a, R5b, R5c, R5d and is independently selected from hydrogen, halogen, hydroxyl, cyano, -NH2, C1-C6 alkyl, C1-C6 alkoxy, C1-C6 haloalkyl, polyhaloalkyl C1-C6 alkylamino C1 C6, and C1-C6 dialkylamino, with the proviso that at least one of R5a, R5b, R5c, R5d and hydrogen; and wherein R6 is selected from hydrogen and C1-C6 alkyl; or a pharmaceutically acceptable salt thereof.