Urea → O-(tert-Butyloxycarbonyl-N,O-dimethyl-L-tyrosyl)-N-benzyloxycarbonyl-L-threonine phenacyl ester

Participants

Reaction Conditions

Reaction Steps

2.00 g (5.38 mmol) of (8), 1.67 g (5.4 mmol) of (9) and 70 mg (0.54 mmol) of DMAP were dissolved in 20 ml of CH2Cl2 and cooled to -30° C., and 1.13 g (5.5 mmol) of DCC were added. The mixture .was allowed to reach RT overnight, the urea was filered off, the filtrate was concentrated, the residue was taken up in ether and left to stand for 1 h, and the urea was again filtered off. Sufficiently pure peptolide (10) was obtained by filtration through silica gel with PE/EA 7/3. Yield: 3.5 g (5.28 mmol, 98%), α!D20 =28.7° (c=0.96, CHCl3)

Provenance & Evidence