1.0 g (2.22 mmol) of 1-amino-2-[(2,6-difluorobenzyl)oxy]-4-methylpyridinium 2,4,6-trimethylbenzenesulphonate from Example 2A were dissolved in 7.2 ml of DMF, and 496 mg (4.00 mmol) of methyl 3-cyclopropylprop-2-ynoate were added. 552 mg (4.00 mmol) of potassium carbonate were added and the mixture was stirred at RT for 3 h. Subsequently, the mixture was poured onto 50 ml of water and stirred briefly, and the precipitated solids were filtered off, washed with water and dried. 384 mg of the title compound were obtained (46% of theory).
