Triethylamine → 4-[6-(1-Amino-3,4-dioxo-1-cyclobuten-2-yl)aminomethylpyridin-2-yl]-2-(diaminomethyleneamino)thiazole hydrochloride

Participants

Reaction Steps

A mixture of 4-(6-aminomethylpyridin-2-yl)-2-(diaminomethyleneamino)thiazole trihydrochloride (1.5 g), triethylamine (1.8 ml) and 1-amino-2-ethoxy-1-cyclobutene-3,4-dione (0.65 g) in methanol (30 ml) was heated under reflux for 7 hours. The solvent was removed by concentration in vacuo. To the residue was added a mixture of water and ethyl acetate, and the mixture was adjusted to pH 1.0 with 6N-hydrochloric acid. The isolated precipitate was collected by filtration and dried. The precipitate was recrystallized from an aqueous N,N-dimethylformamide to give 4-[6-(1-amino-3,4-dioxo-1-cyclobuten-2-yl)aminomethylpyridin-2-yl]-2-(diaminomethyleneamino)thiazole hydrochloride (1.17 g).

Provenance & Evidence