4-Methylmorpholine → 4-(tert-Butyl-dimethyl-silanyloxy)-3-({7-[(naphthalene-2-carbonyl)-amino]-6-oxo-1,3,4,6,7,8,11,11a-octahydro-2H-pyrido[1,2-a]azocine-4-carbonyl}-amino)-butyric Acid Benzyl Ester

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Reaction Steps

7-[(Naphthalene-2-carbonyl)-amino]-6-oxo-1,3,4,6,7,8,11,11a-octahydro-2H-pyrido[1,2-a]azocine-4-carboxylic acid (0.44 gm) is dissolved in 15 mL THF to which 0.24 gm of 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC), 0.15 mL of N-methylmorpholine, and 0.17 gm of 1-hydroxybenzotriazole (HOBt) is added. The reaction mixture is stirred for 20 min then added to a solution of 3-amino-4-(tert-butyl-dimethyl-silanyloxy)-butyric acid benzyl ester (0.52 gm, prepared by methods described in Chem. Pharm. Bull. 1999, 47, 11–21) in 5 mL THF. The resulting mixture is striired at RT for ˜18 h, then poured into water, and extracted with ethyl acetate. The organic layer is washed with saturated aqueous sodium bicarbonate and saturated aqueous sodium chloride, then dried over sodium sulfate powder. Filtration and evaporation produces a crude product which is then purified over silica (1:1 ethylacetate:hexanes) to afford the desired product.

Provenance & Evidence