合成路线1

Synthesis of the intermediate diazepinone (IV) is accomplished by a one-pot synthesis. Condensation of 2-chloro-3-aminopyridine (I) with the anthranilic ester (II) is effected in the presence of potassium tert-butoxide as a catalyst. The resulting anthranilic amide (III) is cyclized under the influence of catalytic amounts of sulfuric acid. Treatment of (IV) with chloroacetylchloride in toluene yields the corresponding choroacetamide (V). The side chain of AQ-RA 741 is prepared starting from 4-picoline, which is alkylated by reaction with 3-(diethylamino)propylchloride in the presence of n-butyllithium. Hydrogenation of (VIII) using platinum dioxide as a catalyst furnishes the diamine (IX), which is coupled with (V) in the presence of catalytic amounts of sodium iodide in acetone leading to AQ-RA 741 as its free base.