Und 458.1210. four.1.28. two(3Hydroxy4methoxyphenyl)3(4trifluoromethoxybenzoyl)6methoxyindole (32)To a wellstirred remedy of compound 20 (0.92 g, 1.60 mmol) in THF (5 mL) at 0 was added TBAF (2.five mL, two.five mmol, 1 M in THF) dropwise. The reaction mixture was stirred for 30 min although warming to area temperature. The reaction mixture was quenched with water (ten mL) and extracted with EtOAc (3 10 mL). The combined organic extract was dried more than Na2SO4 and concentrated beneath decreased pressure. Purification by flash column chromatography making use of a prepacked 50 g silica column [solvent A: EtOAc; solvent B: hexanes; gradient: 12 A / 88 B (four CV), 12 A / 88 B 100 A / 0 B (ten CV), one hundred A / 0 B (4 CV); flow price: 50 mL/min; monitored at 254 and 280 nm] afforded the desired indole totally free phenol ligand 32 (0.43 g, 0.96 mmol, 60 , Rf = 0.33 (50:50 hexanes:EtOAc)) as a yellow powder. 1H NMR ((CD3)2CO, 500 MHz): ten.86 (br s, 1H, NH), 7.91 (d, J = eight.eight Hz, 1H, ArH), 7.69 (s, 1H, OH), 7.65 (d, J = eight.five Hz, 2H, ArH), 7.ten (d, J = 8.5 Hz, 2H, ArH), 7.03 (d, J = 2.2 Hz, 1H, ArH), 6.90 (s, 1H, ArH ), six.87 (dd, J = 8.8 Hz, 2.2 Hz, 1H, ArH), six.71 (m, 2H, ArH), 3.84 (s, 3H, OCH3), 3.77 (s, 3H, OCH3). 13C NMR ((CD3)2CO, 125 MHz): 191.six, 158.1, 151.three (q, Jcf = 2 Hz), 148.9, 147.2, 145.1, 140.five, 137.eight, 132.0, 125.7, 123.7, 122.72, 122.67, 121.7 (q, JCF = 254.75 Hz), 120.7, 116.9, 113.0, 112.3, 111.eight, 95.five, 55.1, 55.8. 19F NMR ((CD3)2CO, 470 MHz): 58.five (s, 6F, OCF3). HPLC: 14.80 min., purity at 254 nm 99 . HRMS (ESI): m/z calculated for C24H19F3NO5 [MH] 458.1210, located 458.1210.NIHPA Author Manuscript NIHPA Author Manuscript NIHPA Author ManuscriptBioorg Med Chem. Author manuscript; available in PMC 2014 November 01.MacDonough et al.Page4.1.29. 2(3Hydroxy4methoxyphenyl)three(3,4,5trimethoxybenzoyl)6hydroxyindole (33)To a wellstirred resolution of compound 21 (0.Dibutyl sulfide uses 40 g, 0.2152673-80-6 Price 59 mmol) in THF (ten mL) at 0 was added TBAF (1.PMID:23671446 00 mL, 1.00 mmol, 1 M in THF) dropwise. The reaction mixture was stirred for 30 min even though warming to room temperature. The reaction mixture was quenched with water (ten mL) and extracted utilizing EtOAc (three ten mL). The combined organic extract was dried more than Na2SO4 and concentrated under lowered pressure. Purification by flash column chromatography working with a prepacked 50 g silica column [solvent A: EtOAc; solvent B: hexanes; gradient: 12 A / 88 B (four CV), 12 A / 88 B 100 A / 0 B (10 CV), 100 A / 0 B (1.four CV); flow rate: 40 mL/min; monitored at 254 and 280 nm] afforded the preferred indole totally free phenol ligand 33 (0.11 g, 0.25 mmol, 42 , Rf = 0.03 (70:30 hexanes:EtOAc)) as a yellow powder. 1H NMR ((CD3)2SO, 500 MHz): 11.62 (br s, 1H, NH), 9.19 (br s, 1H, OH), 9.00 (br s, 1H, OH), 7.66 (d, J = 8.five Hz, 1H, ArH), 6.82 (d, J = two.0 Hz, 1H, ArH) six.78 (s, 2H, ArH), six.74 (d, J = 9.0 Hz, 2H, ArH), six.67 (t, J = two.5 Hz, 1H, ArH), 6.65 (t, J = 3.0 Hz, 1H, ArH), 3.69 (s, 3H, OCH3), three.61 (s, 6H, OCH3), 3.59 (s, 3H, OCH3). 13C NMR ((CD3)2SO, 125 MHz): 192.0, 155.2, 153.four, 148.five, 147.0, 143.7, 141.8, 138.0, 136.4, 126.five, 123.4, 122.7, 122.0, 116.9, 113.1, 112.three, 111.eight, 106.0, 97.four, 60.4, 56.18, 56.17. HPLC: 8.95 min., purity at 254 nm 90.7 . HRMS (ESI): m/z calculated for C25H24NO7 [MH] 450.1547, identified 450.1547. four.1.30. 2(3Hydroxy4methoxyphenyl)three(3,4,5trimethoxybenzoyl)four,5,6trimethoxyindole (34)To a wellstirred resolution of compound 22 (0.03 g, 0.05 mmol) in THF (ten mL) at 0 was added TBAF (0.1 mL, 0.1 mmol, 1 M in THF) dropwise. The reaction mixture was stirred for 30 min whilst warming to.