合成路线1

3-Cyanobenzaldehyde oxime (I) was treated with N-chlorosuccinimide to afford hydroxyiminoyl chloride (II). Subsequent cycloaddition of the intermediate nitrile oxide, generated in situ from (II) and Et3N, with methyl methoxyacrylate (III) produced isoxazole (IV). Then, basic hydrolysis of the ester group, followed by treatment with SOCl2 provided acid chloride (V). Aminobiphenyl (VIII) was obtained by Suzuki coupling of 4-bromoaniline (VI) with boronic acid (VII) using a palladium catalyst. Condensation of (VIII) with acid chloride (V) in the presence of Et3N then gave amide (IX). Alternatively, amide (IX) was obtained by AlMe3-catalyzed condensation of ester (IV) with amine (VIII). Treatment of nitrile (IX) with HCl in MeOH-CHCl3 generated the corresponding iminoester (X) with concomitant cleavage of the N-tert-butyl group. Finally, reaction of this iminoester with methanolic ammonium carbonate afforded the target amidine.