Compound 6

Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

A round-bottomed flask was charged with (1R,3S,5R)-N-((R)-1-(3-chloro-2-fluorophenyl)ethyl)-2-azabicyclo[3.1.0]hexane-3-carboxamide trifluoroacetate salt (19) (21.7 g, 49.2 mmol) and DMF (300 mL). To this solution was added 2-(3-carbamoyl-1H-pyrazolo[3,4-c]pyridin-1-yl)acetic acid (17) (16.5 g, 49.2 mmol), HBTU (22.4 g, 59.1 mmol) and Hünig’s base (40.0 mL, 229 mmol). After stirring at room temperature for 18 h, the solvent (DMF) was evaporated in vacuo and the residual oil was diluted with CH₂Cl₂ to afford a white precipitate. The solid was filtered off, washed with CH₂Cl₂ and dried at 50 °C in vacuo for 1h to give the crude product as a beige solid (22.7g). This material was then dissolved in CH₂Cl₂:MeOH, 9:1 (v/v), the organics were washed with a saturated aqueous NaHCO₃ solution (250 mL), dried and evaporated in vacuo to afford an off-white solid (19.0 g (80% yield); HPLC purity >99% at 215 nm). To this material (10.0 g) was added AcOEt (125 mL) and the mixture was gradually heated up to 55 °C at a rate of 1°C/min with stirring (PolyBLOCK^® reactor, HEL Inc., USA) to provide a solution. After 30 min of stirring at 55 °C, the mixture was cooled at a rate of 0.5°C/min to 5°C where it was held for 30 minutes. This procedure was repeated several times by gradually reducing the maximum heat temperature by about 2 °C/cycle, and the resulting solid was collected by vacuum filtration. Drying at 40 °C in vacuo for 72 h provided 1-(2-((1R,3S,5R)-3-(((R)-1-(3-chloro-2-fluorophenyl)ethyl)carbamoyl)-2-azabicyclo[3.1.0]hexan-2-yl)-2-oxoethyl)-1H-pyrazolo[3,4-c]pyridine-3-carboxamide (6) (9.2 g) as white powder. Melting point 205.9 °C; TLC (CH₂Cl₂:MeOH, 9:1 v/v): RF = 0.60; HPLC t_R = 2.56 min (purity >99% at 215 nm); [α]²⁵_D (deg cm³g^-1 dm^-1) = –95.7 (c = 1 g cm^-3 in MeOH); ¹H NMR (500 MHz, DMSO-d₆) δ 9.14 (s, 1H), 8.39 (d, J = 7.7, 1H), 8.38 (d, J = 5.6 Hz, 1H), 8.07 (d, J = 5.6 Hz, 1H), 7.88 (s, 1H), 7.54 (s, 1H), 7.43 (t, J = 6.9 Hz, 1H), 7.28 (t, J = 6.9 Hz, 1H), 7.09 (t, J = 7.9 Hz, 1H), 5.90 (d, J = 17.4 Hz, 1H), 5.62 (d, J = 17.3 Hz, 1H), 5.05 (m, 1H), 4.30 (dd, J = 9.0, 4.7 Hz, 1H), 3.71 (m, 1H), 2.25 (m, 1H), 2.14 (m, 1H), 1.89 (m, 1H), 1.33 (d, J = 7.0 Hz, 3H), 1.03 (m, 1H), 0.79 (m, 1H); ¹³C NMR (126 MHz, DMSO-d₆) δ 170.0, 166.0, 163.0, 154.4 (d, J = 246 Hz), 140.0, 138.3, 137.6, 135.8, 133.3 (d, J = 14 Hz), 128.8, 126.0 (d, J = 4 Hz), 125.9, 125.2 (d, J = 4 Hz), 119.4 (d, J = 18 Hz), 115.2, 63.2, 51.9, 42.7, 36.8, 31.6, 21.1, 18.1, 17.6; ¹⁹F NMR (376 MHz, DMSO-d₆) δ –122.6; IR (neat): 3406, 3239, 3204, 1682, 1652, 1610, 1552, 1467, 1455 cm^-1; HRMS (m/z): [M+H]⁺ calcd for C₂₃H₂₂ClFN₆O₃, 485.1498; found, 485.1498; analysis (% calcd, % found for C₂₃H₂₂ClF₃N₆O₃): C (56.97, 56.64), H (4.57, 4.42), N (17.33, 17.28).

PubChemID:

318123757

MDL Molfile:

41589_2016_BFnchembio2208_MOESM11_ESM.mol

ChemDraw:

41589_2016_BFnchembio2208_MOESM12_ESM.cdx