A 37 wt/wt % solution of hydrochloric acid (245.95 μL) was added to a solution of N-[2-(diethylamino)ethyl]-N-(2-{[2-(4-hydroxy-2-oxo-2,3-dihydro-1,3-benzothiazol-7-yl)ethyl]amino}ethyl)-3-[2-(1-naphthyl)ethoxy]propanamide (0.56 g) in methanol (5.6 mL) producing a clear solution that was stirred at room temperature for 15 mins. A 0.5 mL aliquot was taken from the bulk of the solution and treated with diethyl ether to form a mobile solid. This suspension was added back to the solution and the mixture was stirred at room temperature for 2 h. The title compound was then collected by filtration, washed with methanol (1.12 mL) and dried on the filter (0.46 g).
