SPT5 inhibitors and uses thereof

A method of treating a nucleotide repeat disorder in a subject in need thereof, the method comprising administering to the subject a therapeutically effective amount of a compound represented by Formula Ia:

• wherein:
• n and m are each independently an integer of from 0 to 4;
• R1 and R2 are each independently a substituent selected from alkyl, cycloalkyl, aryl, heteroaryl, heteroalicyclic, hydroxy, thiol, alkoxy, thioalkoxy, aryloxy, thioaryloxy, halo, alkyl, amine, amide, nitro, carboxylate and thiocarboxylate;
• B is a heteroaryl or a heteroalicyclic;
• and
• L is a linking moiety, comprising from 2 to 12 atoms in length, and comprising a saturated or unsaturated, substituted or unsubstituted hydrocarbon chain, interrupted by at least one S,
• thereby treating a nucleotide repeat disorder in the subject;
• said nucleotide repeat disorder is a trinucleotide repeat disorder selected from Huntington disease, fragile X syndrome, Fragile XE mental retardation, Fragile X-associated tremor/ataxia syndrome, mitotic dystrophy type 1 (DM1), spino-bulbar muscular atrophy (SBMA), Jacobsen syndrome, Spinocerebellar ataxia (SCA) type 1, SCA 2, SCA3 (also known as Machado-Joseph disease), SCA6, SCAT, SCA 7, SCA 8 SCA 12, SCA 17, dentatorubral pallidoluysian atrophy, Friedreich ataxia, Huntington disease-like 2, oculopharyngeal muscular dystrophy, multiple epiphyseal dysplasia, cleidocranial dysplasia, and synpolydactyly.