Triethylamine → HCID 178514012, compound

Participants

Reaction Steps

Separately, (3S)-1-oxo-1,2,3,4-tetrahyroisoquinoline-3-carboxylic acid (70 mg, 0.36 mmole) and N-hydroxysuccinimide (41 mg, 0.36 mmole) are dissolved in DMF (5 ml) and thereto is added DCC (74 mg, 0.36 mmole) under ice-cooling. The mixture is stirred for 1.5 hours. To the solution of the activated ester thus prepared are added the (4R)-3-(L-histidyl)-thiazolidine-4-carboxamide dihydrochloride (150 mg, 0.4 mmole) prepared above and triethylamine (0.21 ml, 0.8 mmole) under ice-cooling. The mixture is stirred at 8° C. for 24 hours. The precipitated DCU is filtered off, and the filtrate is concentrated under reduced pressure. The residue is dissolved in water, and the solution is adjusted to pH 8 with sodium bicarbonate and is passed through a column (2.3×26 cm) packed with CHP-20P resin. The column is washed with water (500 ml) and further with 30% methanol (one liter), and then the product is eluted with 50% methanol. The fractions being positive to Pauly reagent are collected, distilled to remove methanol, and then lyophilized to give (4R)-3-{Nα -[(3S)-1-oxo-1,2,3,4-tetrahydroisoquinoline-3-carbonyl]-L-histidyl}-thiazolidine-4-carboxamide (70 mg, yield: 41.8%).

Provenance & Evidence