[11C] Dimebon (2-[11C] methyl-8-methyl-5-(2-(6-methylpyridin-3-yl) ethyl)-2, 3, 4, 5- tetrahydro-1H-pyrido [4, 3-b] indole), a new potential PET agent for imaging of Alzheimer's disease and Huntington's disease, was prepared by N-[11C] methylation of desmethyl- Domebon precursor with [11C] CH3OTf and purified with a semi-preparative HPLC method in 30–40% decay corrected radiochemical yield and 222–296GBq/μmol specific activity at ...