Radiotracers are important molecular tools in the pharmacologists’ toolbox by enabling visualization of adequately radiolabelled compounds through positron-emission-tomography (PET). In this work, a new and a highly convergent synthesis of a very selective ACE2 inhibitor (and of natural occurring L-ergothioenine) is disclosed. Crucially, one of the aromatic chlorides present in the original drug is exchanged by bromine, allowing the introduction of different radioactive isotopes by means of stannylation and subsequent metal-catalyzed modifications. The synthesis commences with the preparation of imidazole hydrochloride 1 (4 steps) which is used to alkylate a t-butyl-protected glycine equivalent 2 in an enantioselective PTC amino acid synthesis. Compound 3, obtained after cleavage of the imine, was reacted in an optimized reductive amination with α-ketoester 4 to obtain the intermediate 5 in good yield. In turn, the subsequent palladium-catalyzed stannylation was performed by transiently protecting the free amine with MSTFA as a strong silylating agent. The key precursor 6 can be isotopically labelled with 18F (copper-mediated radiofluorination), 11C (Stille coupling) or 124I (electrophilic iodination) to give diverse radiotracers for in vivo imaging and investigation of ACE2, the entry port of SARS-CoV2 in human cells.