6-Formyl-4-isopropoxy-[1,5]naphthyridine-3-carbonitrile → 6-(2-amino-4-oxo-4H-thiazol-5-ylidenemethyl)-4-isopropoxy-[1,5]naphthyridine-3-carbonitrile

Participants

Reaction Conditions

Reaction Steps

To a mixture of pseudothiohydantoin (Aldrich, 97%, 23.2 mg, 0.20 mmol), AcONa (160 mg, 1.95 mmol), molecular sieves, and 6-formyl-4-isopropoxy-[1,5]naphthyridine-3-carbonitrile (53.1 mg, 0.22 mmol) (prepared as described below) in a sealed tube was added AcOH (0.3 mL). The reaction mixture was heated to 85-95° C. for 1.5 h. The reaction mixture was then cooled to r.t. and triturated with water. The solid was collected by filtration and washed with water. The solid was then suspended in hot DMF (20 mL) and filtered again. The filtrate was concentrated to give a brown solid: 55.8 mg, which was then purified by Biotage flash column (1%-6% MeOH in CH2Cl2) to give 6-(2-amino-4-oxo-4H-thiazol-5-ylidenemethyl)-4-isopropoxy-[1,5]naphthyridine-3-carbonitrile as a yellowish solid (15.5 mg, 22.8%). HR-ES (+) m/e calcd for C16H13N5O2S (M+H)+ 340.0863. found 340.0863.

Provenance & Evidence