1: 4-hydroxy-1-methylsulfonylpiperidine With sodium hydride in DMF (N,N-dimethyl-formamide) T=20°C; 0.333333 h; 2: 1-Bromo-2-butyne in DMF (N,N-dimethyl-formamide) T=20°C; 20 h;

1: 4-(but-2-ynyloxy)-1-methanesulphonylpiperidine With lithium hexamethyldisilazane in tetrahydrofuran T=-15°C; 0.5 h; 2: ethyl 4-(pyrimidin-2-yl)-butanoate in tetrahydrofuran T=-15 - 5°C; 0.333333 h;