[CH3:1][C:2]([C:5]1[NH:9][C:8]2[CH2:10][CH2:11][CH2:12][CH2:13][C:14](=[O:15])[C:7]=2[N:6]=1)([CH3:4])[CH3:3].[Cl:16][C:17]1[CH:24]=[CH:23][C:20]([CH2:21]Br)=[CH:19][CH:18]=1.C1(C)C=CC=CC=1.[NH4+].[Cl-]>[Br-].C([N+](CCCC)(CCCC)CCCC)CCC.[OH-].[Na+]>[Cl:16][C:17]1[CH:24]=[CH:23][C:20]([CH2:21][N:6]2[C:7]3[C:14](=[O:15])[CH2:13][CH2:12][CH2:11][CH2:10][C:8]=3[N:9]=[C:5]2[C:2]([CH3:1])([CH3:3])[CH3:4])=[CH:19][CH:18]=1Tetrabutylammonium bromide (1.33 g) was added to a stirred mixture of Intermediate 13 (1.7 g), 4-chlorobenzyl bromide (1.86 g) in sodium hydroxide 20% aq. (12 mL) and toluene (6 mL). The RM was stirred at room temp under nitrogen atm for 3 hours. An excess of sat. NH4Cl aq. solution was added and the mixture was extracted with EtOAc (3×30 ml). The organics were combined, dried (hydrophobic frit) and concentrated under vacuum. The residue was purified on silica using a cyclohexane:ethyl acetate 0-100% gradient. The desired fractions were combined and concentrated under vacuum to give crude material. It was purified by reverse phase chromatography using an acetonitrile-0.1% NH3:water—with an amonium carbonate buffer modifier (pH=10) 5%-95% gradient. The desired fractions were combined and concentrated under vacuum to yield the title compound (650 mg). LC/MS MH+ 331 Rt 2.04 min (5 minute run).
Loading…