4.2. General synthesis of target compounds 13
Various substituted amines 10a-10v (2 mmol) and NaHCO3 (7.4 mmol) were added to 1/1 ethyl acetate/water mixture (5 mL). Subsequently, bromoacetyl bromide (4.6 mmol) was added dropwise to the mixture under ice bath conditions. After dropping, the mixture was stirred at room temperature for 1 h. Progress of the reaction was detected by TCL. Upon completion, the organic layer was separated and the water layer was extracted. The combined organic layer phases were dried and concentrated to obtain 11a-11v. Then compounds 11 (0.6 mmol) was added to a mixture of compound 12 (0.5 mmol) and K2CO3 (0.75 mmol) in N, N-dimethylformamide (5 mL). The mixture was stirred at room temperature for 5 h. Upon completion, the reaction solution was quenched by pouring it into water (50 mL). The suspension was filtered, and the cake was purified by column chromatography (methanol/dichloromethane, 1/200 - 1/50) to obtain target compounds 13.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-(trifluoromethyl) phenyl) acetamide (13a)
White solid, yield 73%, mp:208-212°C, 1H NMR (400 MHz, DMSO-d6) δ 10.73 (s, 1H), 8.20 (s, 1H), 8.02 (s, 1H), 7.69 (d, J = 7.1 Hz, 1H), 7.62 (d, J = 7.5 Hz, 2H), 7.55 – 7.47 (m, 1H), 7.37 (s, 3H), 7.25 – 6.47 (m, 7H), 5.21 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.33, 158.69, 157.69, 156.73, 156.42, 155.71, 144.25, 139.80, 130.62, 130.48, 130.03 (q, J = 31 Hz), 128.22, 124.50 (q, J = 271 Hz), 124.31, 123.24, 120.46 (q, J = 3 Hz), 119.54, 119.43, 115.73 (q, J = 3 Hz), 97.76, 50.15. HRMS(ESI) m/z calcd for C26H19F3N6O2 [M + H]+ 505.1594, found 505.1587.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-nitrophenyl) acetamide (13b)
White solid, yield 71%, mp:236-240°C, 1H NMR (400 MHz, DMSO-d6) δ 10.96 (s, 1H), 8.61 (s, 1H), 8.26 (s, 1H), 7.97 – 7.89 (m, 2H), 7.72 – 7.61 (m, 3H), 7.44 (t, J = 7.9 Hz, 2H), 7.35 – 6.87 (m, 7H), 5.29 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.51, 158.67, 157.68, 156.70, 156.44, 155.69, 148.44, 144.28, 140.11, 130.86, 130.63, 130.48, 128.17, 125.65, 124.32, 119.53, 119.43, 118.67, 113.79, 97.74, 50.16. HRMS(ESI) m/z calcd for C25H19N7O4 [M + H]+ 482.1571, found 482.1568.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-bromophenyl) acetamide (13c)
White solid, yield 71%, mp:188-190°C, 1H NMR (400 MHz, DMSO-d6) δ 10.64 (s, 1H), 8.26 (s, 1H), 7.93 (s, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.58 – 7.39 (m, 4H), 7.37 - 7.25 (m, 3H), 7.22 – 7.11 (m, 5H), 5.24 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.06, 158.67, 157.66, 156.72, 156.41, 155.66, 144.19, 140.60, 131.39, 130.63, 130.47, 128.21, 126.72, 124.32, 122.09, 122.00, 119.53, 119.43, 118.42, 97.71, 50.12. HRMS(ESI) m/z calcd for C25H19BrN6O2 [M + H]+ 515.0826, found 515.0821.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-chlorophenyl) acetamide (13d)
White solid, yield 83%, mp:236-238°C, 1H NMR (400 MHz, DMSO-d6) δ 10.58 (s, 1H), 8.26 (s, 1H), 7.65 (dd, J = 27.0, 5.5 Hz, 4H), 7.41 (d, J = 18.7 Hz, 4H), 7.32 – 6.43 (m, 7H), 5.23 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 165.80, 158.67, 157.66, 156.72, 156.39, 155.64, 144.15, 138.03, 130.62, 130.47, 129.26, 128.23, 127.64, 124.31, 121.21, 119.62, 119.53, 119.42, 97.72, 50.12. HRMS(ESI) m/z calcd for C25H19ClN6O2 [M + H]+ 471.1331, found 471.1328.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-fluorobenzyl) acetamide (13e)
White solid, yield 77%, mp:229-232°C, 1H NMR (400 MHz, DMSO-d6) δ 8.75 (t, J = 5.6 Hz, 1H), 8.26 (s, 1H), 7.67 (d, J = 8.4 Hz, 2H), 7.44 (t, J = 7.8 Hz, 2H), 7.37 (q, J = 7.4 Hz, 1H), 7.25 – 6.68 (m, 10H), 5.07 (s, 2H), 4.34 (d, J = 5.8 Hz, 2H). 13C NMR (100 MHz, DMSO-d6) δ 167.17, 162.74 (d, J = 242 Hz), 158.65, 157.62, 156.74, 156.30, 155.50, 144.12, 142.60 (d, J = 7.2 Hz), 130.67 (d, J = 9 Hz), 130.62, 130.47, 128.30, 124.30, 123.58 (d, J = 2.5 Hz), 119.51, 119.42, 114.24 (d, J = 22 Hz), 114.02 (d, J = 22 Hz), 97.81, 49.70, 42.15. HRMS(ESI) m/z calcd for C26H21FN6O2 [M + H]+ 469.1783, found 469.1780.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-fluorophenethyl) acetamide (13f)
White solid, yield 79%, mp:186-190°C, 1H NMR (400 MHz, DMSO-d6) δ 8.38 - 8.33 (m, 1H), 8.25 (s, 1H), 7.66 (d, J = 8.4 Hz, 2H), 7.44 (t, J = 7.7 Hz, 2H), 7.28 – 7.23 (m, 2H), 7.22 – 6.8 (m, 9H), 4.96 (s, 2H), 3.32 - 3.27 (m, 2H), 2.72 (t, J = 6.3 Hz, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.78, 161.31 (d, J = 240 Hz), 158.62, 157.61, 156.74, 156.30, 155.49, 144.01, 135.92 (d, J = 3 Hz), 130.95 (d, J = 8 Hz), 130.62, 130.47, 128.32, 124.30, 119.50, 119.41, 115.42 (d, J = 21 Hz), 97.72, 49.04, 40.87, 34.48. HRMS(ESI) m/z calcd for C27H23FN6O2 [M + H]+ 483.1940, found 483.1936.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-fluorophenyl) acetamide (13g)
White solid, yield 79%, mp:216-218°C, 1H NMR (400 MHz, DMSO-d6) δ 10.49 (s, 1H), 8.26 (s, 1H), 7.68 (d, J = 8.4 Hz, 2H), 7.62 - 7.59 (m, 2H), 7.44 (t, J = 7.7 Hz, 2H), 7.33 – 6.62 (m, 9H), 5.22 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 170.82, 158.67, 158.61 (d, J = 238 Hz), 157.65, 156.72, 156.38, 155.63, 144.12, 135.48 (d, J = 2.6 Hz), 130.62, 130.47, 128.24, 124.31, 121.42 (d, J = 7.8 Hz), 119.52, 119.42, 115.92 (d, J = 22.2 Hz), 97.73, 50.05. HRMS(ESI) m/z calcd for C25H19FN6O2 [M + H]+ 455.1626, found 455.1617.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-bromophenyl) acetamide (13h)
White solid, yield 80%, mp:238-240°C, 1H NMR (400 MHz, DMSO-d6) δ 10.71 (s, 1H), 8.25 (s, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.59 - 7.54 (m, 3H), 7.51 (d, J = 8.8 Hz, 2H), 7.44 (t, J = 7.9 Hz, 2H), 7.25 – 7.06 (m, 6H), 5.24 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 165.86, 158.65, 157.64, 156.71, 156.38, 155.63, 144.12, 138.58, 132.09, 130.63, 130.47, 128.22, 124.31, 121.55, 119.52, 119.42, 115.58, 97.69, 50.11. HRMS(ESI) m/z calcd for C25H19BrN6O2 [M + H]+ 515.0826, found 515.0819.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-methylbenzyl) acetamide (13i)
White solid, yield 78%, mp:222-226°C, 1H NMR (400 MHz, DMSO-d6) δ 10.33 (s, 1H), 8.38 (d, J = 2.0 Hz, 1H), 8.26 (s, 1H), 8.09 (dd, J = 8.5, 2.4 Hz, 1H), 7.47 - 7.43 (m, 4H), 7.29 – 6.93 (m, 9H), 5.21 (s, 2H), 2.25 (s, 3H). 13C NMR (100 MHz, DMSO-d6) δ 165.34, 158.66, 157.65, 156.73, 156.36, 155.64, 144.08, 136.59, 133.00, 130.62, 130.47, 129.69, 128.28, 124.31, 119.65, 119.52, 119.43, 97.74, 50.09, 20.91. HRMS(ESI) m/z calcd for C26H22N6O2 [M + H]+ 451.1877, found 451.1871.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-cyanophenyl) acetamide (12j)
White solid, yield 69%, mp:228-230°C, 1H NMR (400 MHz, DMSO-d6) δ 10.92 (s, 1H), 8.26 (s, 1H), 7.90 - 7.72 (m, 5H), 7.68 (d, J = 8.4 Hz, 2H), 7.44 (t, J = 7.8 Hz, 2H), 7.32 – 7.05 (m, 6H), 5.29 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.54, 158.67, 157.67, 156.71, 156.43, 155.64, 144.24, 143.23, 133.90, 130.63, 130.47, 128.16, 124.32, 119.72, 119.53, 119.42, 105.87, 97.71, 50.23. HRMS(ESI) m/z calcd for C26H19N7O2 [M + H]+ 462.1673, found 462.1668.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-(trifluoromethyl) phenyl)acetamide (13k)
White solid, yield 67%, mp:228-230°C, 1H NMR (400 MHz, DMSO-d6) δ 10.83 (s, 1H), 8.26 (s, 1H), 7.79 (d, J = 8.6 Hz, 2H), 7.75 – 7.66 (m, 4H), 7.44 (t, J = 7.9 Hz, 2H), 7.24 – 7.08 (m, 7H), 5.28 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.34, 158.69, 157.70, 156.72, 156.42, 155.68, 144.23, 142.61, 130.61, 130.47, 128.22, 126.67 (q, J = 3 Hz), 124.78 (q, J = 269 Hz), 124.31, 124.12 (q, J = 32 Hz), 119.63, 119.54, 119.43, 97.76, 50.21. HRMS(ESI) m/z calcd for C26H19F3N6O2 [M - H]− 503.1454, found 503.1449.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-nitrophenyl) acetamide (13l)
White solid, yield 63%, mp:198-202°C, 1H NMR (400 MHz, DMSO-d6) δ 11.10 (s, 1H), 8.35 – 8.21 (m, 4H), 7.83 (d, J = 9.0 Hz, 2H), 7.68 (d, J = 8.5 Hz, 2H), 7.44 (t, J = 7.6 Hz, 2H), 7.24 – 7.09 (m, 6H), 5.33 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.71, 158.67, 157.69, 156.70, 156.45, 155.67, 145.13, 144.28, 142.97, 130.62, 130.47, 128.16, 125.57, 124.32, 119.54, 119.47, 119.42, 97.73, 50.28. HRMS(ESI) m/z calcd for C25H19N7O4 [M + H]+ 482.1571, found 482.1567.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-chloro-4-fluorophenyl)acetamide (13m)
White solid, yield 74%, mp:226-230°C, 1H NMR (400 MHz, DMSO-d6) δ 10.68 (s, 1H), 8.26 (s, 1H), 7.89 (dd, J = 6.8, 2.1 Hz, 1H), 7.68 (d, J = 8.5 Hz, 2H), 7.51 – 7.36 (m, 5H), 7.23 – 6.92 (m, 6H), 5.23 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 165.97, 158.66, 157.68, 156.71, 156.40, 155.68, 153.74 (d, J = 242 Hz), 144.22, 136.28 (d, J = 3 Hz), 130.61, 130.46, 128.21, 124.30, 121.13, 120.02 (d, J = 7 Hz), 119.70 (d, J = 18 Hz), 119.52, 119.42, 117.55 (d, J = 21 Hz), 97.74, 50.07. HRMS(ESI) m/z calcd for C25H18ClFN6O2 [M + H]+ 489.1237, found 489.1232.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-chloro-4-cyanophenyl)acetamide (13n)
White solid, yield 69%, mp:219-222°C, 1H NMR (400 MHz, DMSO-d6) δ 11.10 (s, 1H), 8.26 (s, 1H), 8.02 (d, J = 1.8 Hz, 1H), 7.94 (d, J = 8.6 Hz, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.61 (dd, J = 8.7, 1.8 Hz, 1H), 7.44 (t, J = 7.9 Hz, 2H), 7.27 – 6.99 (m, 7H), 5.30 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.96, 158.68, 157.72, 156.71, 156.46, 155.71, 144.34, 144.28, 136.58, 135.83, 130.62, 130.47, 128.15, 124.33, 119.70, 119.54, 119.42, 118.37, 116.62, 106.37, 97.75, 50.28. HRMS(ESI) m/z calcd for C26H18ClN7O2 [M + H]+ 496.1283, found 496.1276.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3,4-dicyanophenyl) acetamide (13o)
White solid, yield 72%, mp:228-230°C, 1H NMR (400 MHz, DMSO-d6) δ 11.25 (s, 1H), 8.28 – 8.23 (m, 2H), 8.08 (d, J = 8.7 Hz, 1H), 8.00 – 7.95 (m, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.44 (t, J = 7.9 Hz, 2H), 7.30 – 6.62 (m, 7H), 5.32 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 167.13, 158.67, 157.71, 156.68, 156.46, 155.70, 144.38, 143.45, 135.66, 130.61, 130.46, 128.11, 124.32, 123.64, 123.55, 119.53, 119.41, 116.53, 116.23, 116.09, 108.77, 97.74, 50.27. HRMS(ESI) m/z calcd for C27H18N8O2 [M + H]+ 487.1625, found 487.1618.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-cyano-3-(trifluoromethyl)phenyl)acetamide (13p)
White solid, yield 76%, mp:228-230°C, 1H NMR (400 MHz, DMSO-d6) δ 11.27 (s, 1H), 8.27 (s, 2H), 8.13 (d, J = 8.5 Hz, 1H), 7.95 (d, J = 8.4 Hz, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.44 (t, J = 7.9 Hz, 2H), 7.29 – 6.67 (m, 7H), 5.33 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 167.17, 158.58, 157.72, 156.69, 156.34, 155.66, 144.42, 143.55, 137.16, 132.30 (q, J = 31 Hz), 130.63, 130.47, 128.09, 124.33, 122.85 (q, J = 272 Hz), 122.64, 119.55, 119.42, 117.01 (q, J = 5 Hz), 116.16, 102.54 (q, J = 2 Hz), 97.72, 50.29. HRMS(ESI) m/z calcd for C27H18F3N7O2 [M + H]+ 530.1547, found 530.1541.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(4-bromo-3-(trifluoromethyl)phenyl)acetamide (13q)
White solid, yield 72%, mp:184-187°C, 1H NMR (400 MHz, DMSO-d6) δ 10.83 (s, 1H), 8.20 (s, 1H), 8.11 (s, 1H), 7.77 (d, J = 8.6 Hz, 1H), 7.67 - 7.61 (m, 3H), 7.37 (t, J = 7.4 Hz, 2H), 7.27 – 6.64 (m, 7H), 5.21 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.46, 158.68, 157.70, 156.71, 156.44, 155.70, 144.29, 138.94, 136.14, 130.61, 130.47, 129.10 (q, J = 31 Hz), 128.18, 124.55, 124.31, 123.21 (q, J = 268 Hz), 119.54, 119.42, 118.63 (q, J = 6 Hz), 112.41, 97.75, 50.17. HRMS(ESI) m/z calcd for C26H18BrF3N6O2 [M + H]+ 583.0699, found 4583.0693.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(2-bromophenyl) acetamide (13r)
White solid, yield 82%, mp:184-186°C, 1H NMR (400 MHz, DMSO-d6) δ 10.64 (s, 1H), 8.26 (s, 1H), 7.93 (s, 1H), 7.68 (d, J = 8.6 Hz, 2H), 7.52 – 7.41 (m, 3H), 7.32 – 7.11 (m, 9H), 5.24 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.06, 158.67, 157.66, 156.72, 156.41, 155.66, 144.19, 140.60, 131.39, 130.63, 130.47, 128.21, 126.72, 124.32, 122.09, 122.00, 119.53, 119.43, 118.42, 97.71, 50.12. HRMS(ESI) m/z calcd for C25H19BrN6O2 [M + H]+ 515.0826, found 515.0823.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-chloro-2-fluorophenyl)acetamide (13s)
White solid, yield 69%, mp:200-204°C, 1H NMR (400 MHz, DMSO-d6) δ 10.34 (s, 1H), 8.20 (s, 1H), 7.79 (t, J = 7.4 Hz, 1H), 7.62 (d, J = 8.2 Hz, 2H), 7.37 (t, J = 7.6 Hz, 2H), 7.27 (t, J = 7.2 Hz, 1H), 7.21 - 6.81 (m, 8H), 5.27 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.43, 158.68, 157.69, 156.72, 156.42, 155.67, 149.68 (d, J = 245 Hz), 144.25, 130.62, 130.48, 128.22, 127.71 (d, J = 12 Hz), 126.25, 125.55 (d, J = 5 Hz), 124.31, 123.04, 120.38 (d, J = 16 Hz), 119.53, 119.43, 97.75, 49.89. HRMS(ESI) m/z calcd for C25H18ClFN6O2 [M + H]+ 489.1237, found 489.1232.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(2,3,4-trifluorophenyl)acetamide (13t)
White solid, yield 78%, mp:224-226°C, 1H NMR (400 MHz, DMSO-d6) δ 10.46 (s, 1H), 8.26 (s, 1H), 7.71 – 7.58 (m, 3H), 7.44 (t, J = 7.9 Hz, 2H), 7.34-7.27 (m, 1H), 7.22 – 6.79 (m, 7H), 5.31 (s, 2H). 13C NMR (100 MHz, DMSO-d6) δ 166.46, 158.67, 157.69, 156.72, 156.42, 155.67, 147.50 (d, J = 241 Hz), 144.26, 143.68 (d, J = 238 Hz), 139.66 (d, J = 232 Hz), 130.62, 130.48, 128.20, 124.31, 124.01 (d, J = 5.7 Hz), 119.53, 119.42, 119.01 (d, J = 8 Hz), 112.37 (dd, J = 17.7, 3.6 Hz), 97.75, 49.75. HRMS(ESI) m/z calcd for C25H17F3N6O2 [M + H]+ 491.1438, found 491.1432.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3-bromo-2-methylphenyl)acetamide (13u)
White solid, yield 74%, mp:264-268°C, 1H NMR (400 MHz, DMSO-d6) δ 9.99 (s, 1H), 8.29 (s, 1H), 7.68 (d, J = 8.5 Hz, 2H), 7.45 (q, J = 7.7 Hz, 3H), 7.37 (d, J = 8.8 Hz, 1H), 7.27 – 6.90 (m, 8H), 5.28 (s, 2H), 2.30 (s, 3H). 13C NMR (100 MHz, DMSO-d6) δ 166.09, 158.63, 157.66, 156.70, 156.34, 155.59, 144.21, 137.55, 132.68, 130.63, 130.48, 130.12, 128.23, 127.86, 125.56, 125.25, 124.32, 119.53, 119.42, 97.78, 49.83, 18.68. HRMS(ESI) m/z calcd for C26H21BrN6O2 [M + H]+ 529.0982, found 529.0976.
2-(4-Amino-3-(4-phenoxyphenyl)-1 H -pyrazolo[3,4- d ]pyrimidin-1-yl)- N -(3,5-dimethylphenyl) acetamide (13v)
White solid, yield 81%, mp:250-254°C, 1H NMR (400 MHz, DMSO-d6) δ 10.30 (s, 1H), 8.27 (s, 1H), 7.68 (d, J = 8.5 Hz, 2H), 7.44 (t, J = 7.9 Hz, 2H), 7.31 – 6.72 (m, 9H), 6.72 (s, 1H), 5.20 (s, 2H), 2.22 (s, 6H). 13C NMR (100 MHz, DMSO-d6) δ 165.47, 158.65, 157.62, 156.73, 156.35, 155.67, 144.07, 138.95, 138.27, 130.63, 130.46, 128.27, 125.55, 124.30, 119.51, 119.43, 117.39, 97.70, 50.11, 21.55. HRMS(ESI) m/z calcd for C27H24N6O2 [M + H]+ 465.2034, found 465.2031.