Cycloheptanecarboxylic acid → 4-(2-Cycloheptanecarbonylaminomethylthiazol-4-yl)-2-(diaminomethyleneamino)thiazole

Participants

Reaction Steps

A suspension of 4-(2-aminomethylthiazol-4-yl)-2-(diaminomethyleneamino)thiazole dihydrochloride (2.0 g), cycloheptanecarboxylic acid (1.02 g), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.50 g), 1-hydroxybenzotriazole hydrate (1.07 g) and triethylamine (1.24 g) in N,N-dimethylformamide (50 ml) was stirred at room temperature for 2 hours. The solvent was removed under reduced pressure. The residue was suspended in water (200 ml). The mixture was alkalized to pH 11 with a saturated aqueous potassium carbonate solution and then extracted with a mixture of ethyl acetate (250 ml) and tetrahydrofuran (50 ml). The extract was dried over magnesium sulfate and then was evaporated. The residue was chromatographed on a silica gel column eluting with a mixture of chloroform and methanol =10:1. Recrystallization from a mixture of methanol, tetrahydrofuran and diisopropyl ether afforded 4-(2-cycloheptanecarbonylaminomethylthiazol-4-yl)-2-(diaminomethyleneamino)thiazole (0.72 g).

Provenance & Evidence