To 0.118 g (0.379 mmol) of N-(7-amino-1,3-benzothiazol-2-yl)-2,4,6-trimethylbenzamide and 0.14 mL (1.9 mmol) of propionaldehyde in 5 mL of dichloroethane was added one drop of glacial acetic acid and 0.24 g (1.1 mmol) of sodium triacetoxyborohydride. The mixture was heated to 50° C. for 3 h and an additional 0.14 mL of propionaldehyde was added. The reaction was heated at 50° C. for 18 h and concentrated in vacuo. The crude solid was purified by flash chromatography eluting with a 13% ethyl acetate/hexanes mixture to give 0.080 g (53%) of the title compound as a cream colored powder.
