PRMT5 INHIBITORS

A compound of formula (Ia), (Ib) or (Ic) wherein: n is 1 or 2; RN is H or Me; R1 is optionally one or more halo or methyl groups; R2a and R2b are independently selected from the group consisting of: (i) F; (ii) H; (iii) Me; and (iv) CH2OH; R2c and R2d (if present) are independently selected from the group consisting of: (i) F; (ii) H; (iii) Me; and (iv) CH2OH; R3a and R3b are independently selected from H and Me; R4a is selected from OH, -NH2, -C(=O)NH2, and -CH2OH; R4b is either H or Me; X is either N or CH; R7 is selected from H and C1-4 alkyl; (a) one of R8a, R8b, R8c and R8d is selected from H, halo, C1-4 alkyl, C1-4 alkoxy, NHC1-4 alkyl; (b) another of R8a, R8b, R8c and R8d is selected from H, C1-4 alkyl, C1-4 fluoroalkyl, C3-6 cycloalkyl, C5-6 heteroaryl, C5-6 heteroaryl methyl, C4-6 heterocyclyl, C4-6 heterocyclyl methyl, phenyl, benzyl, halo, amido, amidomethyl, acylamido, acylamidomethyl, C1-4 alkyl ester, C1-4 alkyl ester methyl, C1-4 alkyl carbamoyl, C1-4 alkyl carbamoyl methyl, C1-4 alkylacyl, C1-4 alkylacyl methyl, phenylcarbonyl, carboxy, carboxymethyl, ether, amino, amino methyl, sulfonamido, sulfonamino, sulfone, sulfoxide, nitrile and nitrilemethyl; (c) the others of R8a, R8b, R8c and R8d are H.