4-(2-fluoroethoxy)-3,5-dimethoxyphenethylamine, from his first Helvetica Chimica Acta paper on 4-substituted mescaline derivatives (85:3019, 2002). The 2021 Frontiers pharmacology paper states the compound was 'synthesized as previously described (… Trachsel 2002 …)' and supplied by ReseaChem.