1: N-[2-(tert-butyl-dimethyl-silanyloxy)-ethyl]-4-methyl-benzenesulfonamide With sodium hydride in tetrahydrofuran; mineral oil T=0 - 20°C; 1.5 h; Inert atmosphere; 2: methyl (2E,4E)-6-bromo-2,4-hexadienoate in tetrahydrofuran; mineral oil T=20°C; 20 h; Inert atmosphere; 3: With acetic acid in tetrahydrofuran; water T=20°C; 18 h; Inert atmosphere;