Malonic acid monoethyl ester (I) is converted into beta-ketoester (III) by formation of the corresponding trimethylsilyl ester with TMSCl and pyridine in ether followed by deprotonation with n-BuLi and acylation with cyclopropanecarbonyl chloride (II) in DME. Treatment of (III) with refluxing N,N-dimethylformamide dimethyl acetal (IV) affords enamine (V). Quinoline-5-amine (VI) is first subjected to diazotation by treatment with NaNO2 in H2O/HCl, reduced with SnCl2.2H2O in HCl and isolated as the corresponding dihydrochloride salt (VII) by treatment with HCl. Condensation of enamine (V) with hydrazine (VII) in the presence of Et3N in refluxing EtOH yields pyrazole ester (VIII), which is converted into acylguanidine (X) either by direct heating with guanidine (IX) in EtOH or by first transformation into the corresponding carboxylic acid (XI) by saponification with NaOH in refluxing MeOH, followed by treatment with refluxing thionyl chloride and reaction with guanidine hydrochloride (XII) under Schotten-Baumann conditions in refluxing THF/NaOH. Finally, treatment of the free base (X) with HCl in THF allows isolation of the corresponding monohydrochloride-monohydrate salt .