Vol 000
N. R. Gangarapu, A. Ranganatham, E. K. Reddy, H. D. Surendra,
A. M. Sajith, S. Yellappa, and K. B. Chandrasekhar
8.16–8.08 (m, 14H), 7.81–7.71 (m, 12H), 7.54 (dd, J = 4.1,
2.5 Hz, 24H), 7.13 (dd, J = 9.0, 4.7 Hz, 11H), 6.93 (dd,
J = 13.0, 5.4 Hz, 23H). 13C NMR (101 MHz, DMSO) δ
115.57, 115.82, 119.83, 120.05, 126.23, 127.33, 128.38,
129.09, 129.19, 130.25, 130.78, 132.33, 132.41, 134.51,
134.72, 135.21, 140.38, 143.53, 151.66, 158.51, 160.97,
167.12. UPLC-MS: m/z calculated for C23H15ClFN3O:
403.10; observed mass: 402.3 (M ꢀ 1); Elemental
Dimethyl-4,40-(3-(picolinamido)pyrazine-2,6-diyl)dibenzoate
(5g). Off white solid; yield 52 mg, 82%; melting range:
187–189°C; 1H NMR (400 MHz, DMSO) δ 11.13 (s,
1H), 9.28 (s, 1H), 8.76 (s, 1H), 8.72 (d, J = 4.3 Hz, 1H),
8.51 (d, J = 8.0 Hz, 1H), 8.47 (s, 1H), 8.14 (dd, J = 17.0,
7.9 Hz, 2H), 8.06–7.96 (m, 3H), 7.75 (t, J = 7.8 Hz, 1H),
7.69 (ddd, J = 7.2, 4.8, 1.4 Hz, 1H), 7.62 (t, J = 7.8 Hz,
1H), 3.92 (s, 3H), 3.89 (s, 3H). 13C NMR (101 MHz,
DMSO) δ 166.38, 163.42, 149.34, 149.14, 148.13,
144.70, 139.91, 138.60, 138.21, 136.46, 133.27, 131.91,
131.06, 130.83, 130.38, 130.15, 129.43, 127.76, 122.89,
52.76. UPLC-MS: m/z calculated for C26H20N4O5:
468.14; observed mass: 467.3 (M ꢀ 1); Elemental
Analysis: C, 68.41; H, 3.74; Cl, 8.78; N, 10.42.
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)-2-chloro-
5-fluorobenzamide (5c). White solid; yield 53 mg, 76%;
1
melting range: 153–155°C; H NMR (400 MHz, CDCl3)
δ 9.03 (s, 1H), 8.17–8.08 (m, 2H), 7.79–7.71 (m, 2H),
7.54 (dd, J = 4.1, 2.5 Hz, 4H), 7.13 (dd, J = 9.0, 4.7 Hz,
2H), 6.91 (d, J = 7.8 Hz, 2H). 13C NMR (100 MHz,
DMSO) δ 115.60, 115.77, 116.02, 120.06, 120.27,
126.06, 126.22, 126.34, 128.29, 129.39, 132.43, 132.51,
134.38, 138.17, 141.94, 144.53, 150.31, 150.45, 158.56,
166.99. UPLC-MS: m/z calculated for C25H13ClF7N3O:
539.06; observed mass: 539.1 (M ꢀ 1); Elemental
Analysis calculated for C25H13ClF7N3O: C, 55.61; H,
2.43; N, 7.81; found C, 55.63; H, 2.44; N, 7.80.
N-(3,5-bis(4-chlorophenyl)pyrazin-2-yl)picolinamide (5d).
White crystalline solid; yield 50 mg, 78%; melting range:
191–193°C; 1H NMR (400 MHz, DMSO) δ 11.09 (s,
1H), 9.22 (s, 1H), 8.75 (s, 1H), 8.28 (d, J = 8.0 Hz, 2H),
8.10–7.88 (m, 4H), 7.77–7.61 (m, 3H), 7.54 (d,
J = 7.8 Hz, 2H). 13C NMR (101 MHz, DMSO) δ 149.26,
147.84, 139.35, 138.63, 130.47, 129.56, 128.93, 127.80,
122.92. UPLC-MS: m/z calculated for C22H14Cl2N4O:
420.05; observed mass: 419.2 (M + 1); Elemental
Analysis: C, 62.72; H, 3.36; N, 13.31.
Analysis: C, 66.64; H, 4.32; N, 11.96.
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)
nicotinamide (5i). White solid; yield 48 mg, 78%; melting
1
range: 191–193°C; H NMR (400 MHz, DMSO) δ 11.48
(s, 1H), 9.33 (s, 1H), 9.04 (s, 1H), 8.75 (dd, J = 1.2 Hz,
8.8 Hz, 1H), 8.47 (d, J = 8.0 Hz, 2H), 8.20 (dd,
J = 8.0 Hz, 1H), 8.12 (dd, J = 8.0 Hz, 2H), 7.96 (dd,
J = 8.0 Hz, 2H), 7.83 (dd, J = 8.0 Hz, 2H), 7.57–7.53
(m, 1H). UPLC-MS: m/z calculated for C24H14F6N4O:
488.11; observed mass: 490.2 (M + 1); Elemental
Analysis: C, 59.04; H, 2.90; N, 11.48.
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)-6-
chloronicotinamide (5j). Pale brown solid; yield 51 mg,
77%; melting range: 186–188°C; 1H NMR (400 MHz,
DMSO) δ 8.74 (s, 1H), 8.23–8.21 (m, 2H), 8.04–8.01 (m,
3H), 7.89–7.87 (m, 3H), 7.80–7.78 (m, 2H), 6.72 (m,
2H). 13C NMR (101 MHz, CDCl3) δ 128.13, 128.29,
130.60, 130.82, 130.99, 132.81, 133.13, 133.54, 133.87,
134.19, 134.35, 141.78, 143.13, 144.82, 145.86, 146.59,
158.06. UPLC-MS: m/z calculated for C24H13ClF6N4O:
522.07; observed mass: 518.9 (M ꢀ 3); Elemental
N-(3,5-diphenylpyrazin-2-yl)picolinamide
(5e).
Pale
brown solid; yield 52 mg, 74%; melting range: 176–
1
177°C; H NMR (400 MHz, DMSO) δ 11.06 (s, 1H),
Analysis: C, 55.14; H, 2.52; N, 10.74.
9.27–9.15 (m, 1H), 8.78–8.69 (m, 1H), 8.33–8.21 (m,
2H), 8.09–7.99 (m, 2H), 7.98–7.90 (m, 2H), 7.74–7.61
(m, 3H), 7.61–7.49 (m, 2H). 13C NMR (101 MHz,
DMSO) δ 163.31, 149.29, 147.86, 144.24, 139.37,
138.65, 136.49, 135.31, 134.69, 134.44, 130.49, 129.58,
128.96, 127.86, 122.94, 117.39. UPLC-MS: m/z
calculated for C22H16N4O: 352.13; observed mass: 353.2
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)-2-
chloronicotinamide (5k). White solid; yield 50 mg, 75%;
1
melting range: 208–210°C; H NMR (400 MHz, DMSO)
δ 9.56 (s, 1H), 8.46–8.45 (m, 2H), 8.03–7.87 (m, 8H),
7.48–7.44 (m, 2H). 13C NMR (101 MHz, DMSO):
122.776, 123.059, 125.327, 125.477, 125.872, 127.522,
128.801, 129.037, 129.346, 129.755, 130.074, 131.663,
138.180, 139.069, 139.827, 141.533, 143.771, 146.482,
146.606, 147.065, 150.871, 163.662. UPLC-MS: m/z
calculated for C24H13ClF6N4O: 523.07; observed mass:
522.2 (M ꢀ 1); Elemental Analysis: C, 55.14; H, 2.52;
(M + 1); Elemental Analysis: C, 74.98; H, 4.58; N, 15.90.
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)
picolinamide (5f). White solid; yield 50 mg, 80%; melting
1
range: 183–185°C; H NMR (400 MHz, DMSO) δ 11.18
(s, 1H), 9.34 (S, 1H), 8.74 (S, 1H), 8.46 (d, J = 8.2 Hz,
2H), 8.11 (d, J = 8.4 Hz, 2H), 8.03–8.01 (m, 2H),
7.98–7.94 (m, 2H), 7.84 (d, J = 8.2 Hz), 7.71–7.68
(m, 1H). 13C NMR (101 MHz, DMSO): 122.48,
125.29, 125.89, 127.41, 127.54, 128.93, 138.18, 139.12,
139.99, 141.29, 144.51, 147.08, 148.72, 162.86. UPLC-
MS: m/z calculated for C24H14F6N4O: 488.10; observed
mass: 490.1 (M + 1); Elemental Analysis: C, 59.03; H,
2.90; N, 11.48.
N, 10.74.
N-(3,5-bis(4-(trifluoromethyl)phenyl)pyrazin-2-yl)-3-
(trifluoromethyl)benzamide (5l). White solid; yield 50 mg,
70%; melting range: 206–208°C; 1H NMR (400 MHz,
DMSO) δ 9.52 (s, 1H), 8.46 (d, J = 8.0 Hz, 2H), 7.98–
7.93 (m, 2H), 7.93–7.85 (m, 3H), 7.66 (m, 3H), 7.60 (m,
3H), 13.14 (s, 1H), 8.74 (s, 1H), 8.22 (d, J = 8.0 Hz,
1H), 8.03 (d, J = 8.0 Hz, 1H), 7.88 (d, J = 8.0 Hz, 1H),
7.79 (d, J = 8.0 Hz, 1H), 7.67 (d, J = 8.0 Hz, 1H), 7.50
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet