7.2 ml of 32% hydrochloric acid (Merck, Darmstadt, Germany; p.a.) are added, with stirring, to a mixture of 4.92 g (0.024 mol) of 4-(N-hydroxyamidino)-2,3-dihydro-1H-inden-1-one oxime, 4.9 g (0.024 mol) of 1,2-diamino-4-(4-methoxyphenyl)-imidazole (see Hetzheim A. et al., Chem. Ber. 100, 3418 (1967)) and 120 ml of isopropanol, and the reaction mixture is stirred at 80° C. for 19 hours. The reaction mixture is filtered while hot and the filtrate is cooled. The pale-yellow title product that has crystallised out is filtered off with suction and dried. It crystallizes in the form of the monohydrate, m.p. >220° C., MS (FAB): (M+H)+ =377, 1H-NMR (DMSO/D2O): δ=8.23 (d, 1H); 7.74 (s, 1H); 7.72 (d, 1H); 7.57-7.63 (m, 3H); 7.02 (d, 2H); 3.75 (s, 3H), 3.26 (s, 4H).
