Abstract: A manufacturing process for the preparation of radiolabeled compounds of formula (I) includes reacting compounds of formula (II) with a source of readionuclide of a halogen in the presence of an oxidant under acidic condition, wherein: *I is 123I, 124I, 125I or 131I; R is lower alkyl, optionally substituted with one or more fluorine atoms; Q is C(O), O, NR?, S, S(O)2, C(O)2, (CH2)p; Y is C(O), O, NR?, S, S(O)2, C(O)2, (CH2)p; R? is H, C(O), S(O)2, C(O)2; Z is H, C1-C4 alkyl, benzyl, substituted benzyl or trialkylsilyl; m is 0, 1, 2, 3, 4 or 5; n is 0, 1, 2, 3, 4, 5 or 6; and p is 0, 1, 2, 3, 4, 5 or 6.