4-Methylmorpholine → HCID 131718971, compound

Participants

Reaction Conditions

Reaction Steps

Z-Pro (2.18 g, 8.3 mmol) and Trp-Tle-Leu-OEt (prepared by catalytic hydrogenation of Z-Trp-Tle-Leu-OEt over palladium on charcoal) (3.47 g, 7.6 mmol), and NMM (0.92 mL) are dissolved in 35 mL DMF, cooled to 0° C., and treated with TBTU (2.66 g, 8.3 mmol). The reaction is stirred at 0° C. for 1 hour then removed from the ice bath and stirred at room temperature for 2 hours. The mixture is poured into 350 mL of a saturated solution of sodium bicarbonate which is then extracted with 350 mL of ethyl acetate. The combined organic extracts are washed with 350 mL of 1 M KHSO4, water and brine, and then dried over sodium sulfate. The solvents are removed and the residue chromatographed on silica gel (1.5% MeOH in chloroform) to give Z-Pro-Trp-Tle-Leu-OEt (Seq ID No: 7) (4.7 g). FABMS M+1 690

Provenance & Evidence