A mixture of (S)-1-[1-(trans-3-benzyloxycyclobutyl)-6-fluoro-1H-benzoimidazol-2-yl]ethylamine (210 mg, 0.62 mmol), 6-chloro-9-(tetrahydropyran-2-yl)-9H-purine (148 mg, 0.62 mmol) and DIPEA (0.55 mL, 3.09 mmol) in IPA (5 mL) was heated at 90° C. in a sealed vial for 16 h. After cooling to RT, the reaction mixture was concentrated in vacuo, dissolved in DCM and loaded onto an Isolute® SCX-2 cartridge which was washed with DCM, MeOH followed by 2M NH3/MeOH. The product containing fractions were combined and concentrated in vacuo. The resulting residue was purified by column chromatography (Si—PCC, gradient 0-5% 2M NH3/MeOH in DCM) to afford the title compound as a colourless glassy solid (120 mg, 43%). LCMS (Method J): RT 2.72 min [M+H]+ 458
