4-Methylmorpholine → N-Boc-S-(cyanomethyl)-L-cysteine-L-proline-O-benzyl ester

Participants

Reaction Steps

The compound of Example 43 (24.72, 95.06 mmole) and L-proline-O-benzyl ester hydrochloride (22.98 g, 95.06 mmole) are suspended in 140 mL of acetonitrile and 120 mL of DMF at 0° C., then BOP (42.0 g, 95.06 mmole) and NMM (28.84 g, 285.18 mmole) are added. The ice bath is removed after 30 minutes and the reaction is stirred for 18 hours at room temperature. The reaction mixture is reduced in volume under vacuum at 25° C. to give a residue. The residue is taken up in 200 mL ethyl acetate, and is washed successively with 1N hydrochloric acid (1×50 mL) saturated sodium bicarbonate 1×50 mL) and brine (1×50 mL). After drying with MgSO4, the solvent is evaporated under vacuum to give the title compound.

Provenance & Evidence