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M. Gao et al. / Chinese Chemical Letters 22 (2011) 823–826
Combined organic fractions were concentrated under vacuum and subsequently purified by flash chromatography on silica gel (EtOAc:n-
hexane, 1:10) to give the products 5a–j.
;
[17] The data of new compounds: 5b: mp: 141–142 8C. IR (NaCl): 3420, 3321, 1664, 1612 cmꢀ1 1H NMR (600 MHz, CDCl3): d 1.24 (t, 3H,
J = 6.6 Hz, CH3), 2.38 (s, 3H, CH3-CO), 4.12 (m, 2H, CH2), 5.33 (s, 1H, CH pyridazine), 6.21 (s, 2H, NH2), 7.22–7.84 (m, 9H, ArH); 13C NMR
(600 MHz, CDCl3): d 14.43, 24.88, 33.95, 59.66, 76.52, 125.73, 126.11, 126.83, 127.29, 127.65, 127.91, 129.03, 132.44, 139.66, 141.58,
147.37, 148,21, 150.31, 152.79, 168.95, 196.60; HRMS calcd. for C21H20N4O5[M+] 408.1434, found 408.1440. 5c: mp: 151–152 8C. IR
(NaCl): 3429, 3322, 1668, 1614 cmꢀ1. 1H NMR (600 MHz, CDCl3): d 1.25 (t, 3H, J = 7.2 Hz, CH3), 2.39 (s, 3H, CH3-CO), 4.13 (m, 2H, CH2),
5.41 (s, 1H, CH pyridazine), 6.28 (s, 2H, NH2), 7.26–7.66 (m, 7H, ArH), 8.01 (d, 2H, J = 8.4 Hz, ArH); 13C NMR (600 MHz, CDCl3): d 14.45,
24.86, 33.94, 59.68, 76.51, 125.77, 126.22, 126.83, 127.39, 127.61, 127.92, 129.03, 132.44, 139.66, 141.58, 147.39, 148.11, 150.31, 152.79,
168.90, 196.61; HRMS calcd. for C21H20N4O5[M+] 408.1434, found 408.1437. 5d: mp: 174–175 8C. IR (NaCl): 3430, 3321, 1664, 1610 cmꢀ1
;
1H NMR (600 MHz, CDCl3): d 1.23 (t, 3H, J = 6.6 Hz, CH3), 2.39 (s, 3H, CH3-CO), 4.11 (m, 2H, CH2), 5.44 (s, 1H pyridazine), 6.25 (s, 2H,
NH2), 7.26–7.56 (m, 7H, ArH), 8.13 (d, 2H, J = 8.4 Hz, ArH); 13C NMR (600 MHz, CDCl3): d 14.43, 24.84, 33.95, 59.61, 75.92, 125.73,
126.11, 126.83, 127.29, 127.64, 127.93, 129.02, 132.41, 139.62, 141.58, 141.91, 147.38, 150.30, 152.77, 168.88, 196.61; HRMS calcd for
C
21H20N4O5[M+] 408.1434, found 408.1436. 5e: mp: 171–172 8C. IR (NaCl): 3433, 3327, 1663, 1611 cmꢀ1; 1H NMR (600 MHz, CDCl3): d
1.24 (t, 3H, J = 6.6 Hz, CH3), 2.38 (s, 3H, CH3-CO), 4.12 (m, 2H, CH2), 5.32 (s, 1H pyridazine), 6.24 (s, 2H, NH2), 7.22–7.55 (m, 9H, ArH);
13C NMR (600 MHz, CDCl3): d 14.44, 24.83, 33.96, 59.62, 75.91, 125.75, 126.12, 126.86, 127.30, 127.62, 127.91, 129.02, 132.41, 139.62,
141.58, 141.91, 147.38, 150.30, 152.77, 168.81, 196.60; HRMS calcd. for C21H20ClN3O3[M+] 397.1198, found 397.1202. 5f: mp: 175–176 8C.
IR (NaCl): 3440, 3318, 1668, 1629 cmꢀ1; 1H NMR (600 MHz, CDCl3): d 1.23 (t, 3H, J = 7.2 Hz, CH3), 2.38 (s, 3H, CH3-CO), 4.12 (m, 2H,
CH2), 5.32 (s, 1H pyridazine), 6.20 (s, 2H, NH2), 7.22–7.54 (m, 8H, ArH); 13C NMR (600 MHz, CDCl3): d 14.43, 24.88, 33.99, 59.64, 75.93,
125.76, 126.12, 126.86, 127.30, 127.62, 127.91, 129.02, 132.41, 139.62, 141.58, 141.91, 147.38, 150.30, 152.77, 168.85, 196.61; HRMS calcd
for C21H19Cl2N3O3[M+] 431.0803, found 431.0810. 5g: mp: 155–156 8C. IR (NaCl): 3460, 3298, 1683, 1633 cmꢀ1 1H NMR (600 MHz,
;
CDCl3): d 1.24 (t, 3H, J = 6.6 Hz, CH3), 2.38 (s, 3H, CH3-CO), 4.12 (m, 2H, CH2), 5.30 (s, 1H pyridazine), 6.22(s, 2H, NH2), 7.22–7.53 (m, 9H,
ArH); 13C NMR (600 MHz, CDCl3): d 14.44, 24.86, 33.96, 59.66, 75.95, 125.76, 126.12, 126.86, 127.30, 127.62, 127.91, 129.02, 132.42,
139.65, 141.59, 141.92, 147.37, 150.30, 152.77, 168.85, 196.60; HRMS calcd. for C21H20BrN3O3[M+] 441.0688, found 441.0693. 5h: mp:
165–166 8C. IR (NaCl): 3470, 3298, 1688, 1634 cmꢀ1; 1H NMR (600 MHz, CDCl3): d 1.23 (t, 3H, J = 7.2 Hz, CH3), 2.37 (s, 3H, CH3-CO),
4.12 (m, 2H, CH2), 5.32 (s, 1H pyridazine), 6.20 (s, 2H, NH2), 7.22–7.54 (m, 9H, ArH); 13C NMR (600 MHz, CDCl3): d 14.43, 24.86, 33.95,
59.64, 75.90, 120.52, 125.76, 126.12, 126.86, 127.30, 127.62, 127.91, 129.02, 132.42, 139.65, 141.59, 141.92, 147.37, 150.30, 152.77, 168.88,
1
196.61; HRMS calcd. for C22H20N4O3[M+] 388.1535, found 388.1542. 5i: mp: 175–174 8C. IR (NaCl): 3477, 3299, 1688, 1644 cmꢀ1; H
NMR (600 MHz, CDCl3): d 1.24 (t, 3H, J = 6.6 Hz, CH3), 2.36 (s, 3H, CH3-CO), 3.75 (s, 3H, OCH3), 4.12 (m, 2H, CH2), 5.29 (s, 1H
pyridazine), 6.20 (s, 2H, NH2), 7.20–7.51 (m, 9H, ArH); 13C NMR (600 MHz, CDCl3): d 14.43, 24.86, 33.95, 55.1, 59.64, 75.90, 120.52,
125.76, 126.12, 126.86, 127.30, 127.62, 127.91, 129.02, 132.42, 141.59, 147.37, 150.30, 159.1, 152.77, 168.88, 196.61; HRMS calcd. for
C
22H23N3O4[M+] 393.1689, found 393.1696. 5j: mp: 214–215 8C. IR (NaCl): 3426, 3290, 1664, 1627 cmꢀ1; 1H NMR (600 MHz, CDCl3): d
1.24 (t, 3H, J = 6.6 Hz, CH3), 2.38 (s, 3H, CH3-CO), 3.75 (s, 3H, OCH3), 4.11 (m, 2H, CH2), 5.25 (s, 1H, OH), 5.29 (s, 1H pyridazine), 6.20 (s,
2H, NH2), 7.14–7.51 (m, 9H, ArH); 13C NMR (600 MHz, CDCl3): d 14.43, 24.85, 33.95, 59.62, 75.95, 125.73, 126.10, 126.86, 127.30, 127.62,
127.91, 129.02, 132.42, 139.65, 141.59, 141.92, 147.37, 150.30, 152.77, 168.85, 196.60; HRMS calcd. for C21H21N3O4[M+] 397.1532, found
379.1540.