Trifluoroacetic acid → H-L-Ile-D-Pro-OBzl-TFA

HRID 1725101Notes

Reaction equation

HRID 1725101 reaction equation
[NH:1](C(OC(C)(C)C)=O)[C@H:2]([C:7]([N:9]1[CH2:23][CH2:22][CH2:21][C@@H:10]1[C:11]([O:13][CH2:14][C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1)=[O:12])=[O:8])[C@H:3]([CH2:5][CH3:6])[CH3:4].[C:31]([OH:37])([C:33]([F:36])([F:35])[F:34])=[O:32]>>[NH2:1][C@H:2]([C:7]([N:9]1[CH2:23][CH2:22][CH2:21][C@@H:10]1[C:11]([O:13][CH2:14][C:15]1[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=1)=[O:12])=[O:8])[C@H:3]([CH2:5][CH3:6])[CH3:4].[F:34][C:33]([C:31]([OH:37])=[O:32])([F:36])[F:35]

Participants

3

Reactant 2

HCID 6422Trifluoroacetic acid2×HCID 58726192HCID 58726192, compound

Product 1

HCID 131727275H-L-Ile-D-Pro-OBzl-TFA

Procedure

Boc-L-Ile-D-Pro-OBzl (21.5 g, 51.4 mmol) was dissolved in TFA (50 ml) and left with standing on ice for one hour. On completion of the reaction, TFA was removed by evaporation, and the residue was vacuum-dried to obtain H-L-Ile-D-Pro-OBzl-TFA. The compound was dissolved in DMF (100 ml), and Boc-D-Tyr(Me)-OH (16.7 g, 56.5 mmol) was then added. HBTU (29.4 g, 77 mmol), HOBt.H2O (7.87 g, 51 mmol), and triethylamine (25.2 ml, 180 mmol) were further added and stirred for 3 hours under ice-cooling. The reaction solution was concentrated, dissolved in ethyl acetate, and successively washed with an aqueous 10% citric acid solution, an aqueous 4% sodium bicarbonate solution, and saturated saline. The product was dried over MgSO4 and concentrated, and the resulting foam substance was purified by flash silica gel chromatography (4×30 cm, 1% methanol/chloroform) to obtain the foam title compound (22.0 g, 37 mmol, 72% yield). TLC: Rf=(CHCl3/MeOH=9/1).

Workup

  1. waitleft
  2. customwas removed by evaporation
  3. customthe residue was vacuum-dried

Sources & evidence

ORD record
ord-26a131f0ec664593a97203b285bdf3be
Source dataset
uspto-grants-2009_02
Patent number
US07488712B2

Reaction notes

Loading…