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130.7, 129.1, 128.8, 127.9, 127.5, 126.7, 123.2, 43.4; MS (ESI) m/z 295.1
[MþH]þ; HRMS (ESI) calcd for [C17H14N2OSþH]þ 295.0899, found
295.0900.
14.7; MS (ESI) m/z 248.1 [MþH]þ; HRMS (ESI) calcd for
[C13H13NO4þH]þ 248.0917, found 248.0920.
4.2.20. Methyl2-(4-(trifluoromethyl)phenyl)oxazole-4-carboxylate
(4d). White solid; mp: 123e124 ꢀC; IR (KBr) 3135, 3087, 2968, 1728,
4.2.13. N-Benzyl-2-(4-methoxyphenyl)thiazole-4-carboxamide
(2m). White solid; mp 128e130 ꢀC; IR (KBr) 3345, 2938, 2825,1648,
1442, 1414, 1384, 1328, 1257, 1201, 1176, 1151, 1074, 849 cmꢁ1 1H
;
1610, 1480, 1304, 1253, 1110, 838,706 cmꢁ1
;
1H NMR (300 MHz,
NMR (300 MHz, CDCl3)
d
8.34 (s, 1H), 8.24 (d, 2H, J¼8.4 Hz), 7.75 (d,
CDCl3)
d
8.07 (s, 1H), 7.82 (s, 1H), 6.93e7.88 (m, 4H), 7.29e7.39 (m,
168.2,
2H, J¼8.4 Hz), 3.98 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 161.4, 161.1,
5H), 4.68 (d, 2H), 3. 86 (s, 3H); 13C NMR (75 MHz, CDCl3)
d
144.3, 134.8, 133.0, 132.6, 129.5, 127.2, 126.0, 125.9, 125.9, 125.8,
125.5, 121.8, 52.3; MS (ESI) m/z 272.0 [MþH]þ; HRMS (ESI) calcd for
[C12H8F3NO3þH]þ 272.0538, found 272.0529.
161.6,160.6,150.3,138.2,128.7,128.2,127.9,127.5,125.6,122.3,114.4,
55.5, 43.4; MS (ESI) m/z 325.1 [MþH]þ; HRMS (ESI) calcd for
[C18H16N2O2SþH]þ 325.1005, found 325.0999.
4.2.21. Methyl 2-(4-chlorophenyl)oxazole-4-carboxylate (4e). White
solid; mp: 152e154 ꢀC; IR (KBr) 3103, 2914, 2849, 1736, 1642, 1492,
4.2.14. N-Benzyl-2-(3,4-dimethoxyphenyl)thiazole-4-carboxamide
(2n). White solid; mp 98e100 ꢀC; IR (KBr) 3398, 3091, 2920,
1370, 1314, 1282, 1214, 1117, 1093, 1062, 844 cmꢁ1 1H NMR
;
2849, 1659, 1465, 1437, 1268, 1243, 1024, 762 cmꢁ1 1H NMR
;
(300 MHz, CDCl3)
NMR (75 MHz, CDCl3)
d C
8.29 (s, 1H), 7.44e8.06 (m, 4H), 3.96 (t, 3H); 13
(300 MHz, CDCl3)
7.26e7.37 (m, 5H), 4.68 (d, 2H), 3. 93 (s, 6H); 13C NMR (75 MHz,
CDCl3) 168.3, 161.1, 151.3, 150.4, 149.3, 138.3, 128.7, 127.8, 127.5,
d 8.08 (s, 1H), 7.80 (s, 1H), 6.88e7.47 (m, 3H),
d
168.4, 161.6, 143.9, 137.5, 130.0, 129.2, 128.5,
128.1, 52.3; MS (ESI) m/z 238.0 [MþH]þ; HRMS (ESI) calcd for
[C11H8ClNO3þH]þ 238.0259, found 238.0265.
d
125.9, 122.6, 120.1, 111.1, 109.2, 56.1, 55.0, 43.3; MS (ESI) m/z 355.1
[MþH]þ; HRMS (ESI) calcd for [C19H18N2O3SþH]þ 355.1104, found
355.1106.
4.2.22. Methyl 2-(4-bromophenyl)oxazole-4-carboxylate (4f). White
solid; mp: 154e156 ꢀC; IR (KBr) 3109, 2920, 2849, 1736, 1642,1484,
1369, 1314, 1279, 1262, 1117, 1092, 1011, 835 cmꢁ1 1H NMR
;
4.2.15. N-Benzyl-2-(4-(trifluoromethyl)phenyl)thiazole-4-
carboxamide (2o). White solid; mp: 105e108 ꢀC; IR (KBr) 3341,
(300 MHz, CDCl3)
NMR (75 MHz, CDCl3)
d C
8.29 (s, 1H), 7.60e7.99 (m, 4H), 3.96 (t, 3H); 13
d
166.7, 166.6, 143.9, 134.5, 132.2, 128.3, 125.9,
2927, 1654, 1544, 1485, 1409, 1254, 1065, 848, 703 cmꢁ1 1H NMR
;
125.2, 52.3; MS (ESI) m/z 282.1 [MþH]þ; HRMS (ESI) calcd for
(300 MHz, CDCl3)
d 8.19 (s, 1H), 7.80 (s, 1H), 7.66e8.03 (m, 4H),
[C11H8BrNO3þH]þ 281.9760, found 281.9761.
7.25e7.39 (m, 5H), 4.68 (d, 2H); 13C NMR (75 MHz, CDCl3)
d
165.8, 160.1, 151.5, 139.9, 136.4, 131.1, 130.7, 128.6, 127.8, 127.5,
4.2.23. N-Benzyl-2-(4-methoxyphenyl)oxazole-4-carboxamide
(4g). White solid; mp: 134e136 ꢀC; IR (KBr) 3305, 3116, 3080, 1650,
1612, 1592, 1514, 1498, 1452, 1439, 1384, 1331, 1256, 1183, 1166, 1101,
127.4, 127.1, 126.4, 125.8, 125.7, 42.8; MS (ESI) m/z 363.1 [MþH]þ;
HRMS (ESI) calcd for [C18H13F3N2OSþH]þ 363.0773, found
363.0772.
1027, 838 cmꢁ1 1H NMR (300 MHz, CDCl3)
; d 8.21 (s, 1H), 7.95 (d,
2H, J¼8.7 Hz), 7.27e7.38 (m, 6H), 6.96 (d, 2H, J¼8.7 Hz), 4.64 (d, 2H,
4.2.16. N-Benzyl-2-(4-nitrophenyl)thiazole-4-carboxamide
J¼6.0 Hz), 3.86 (s, 3H); 13C NMR (75 MHz, CDCl3)
d 161.8, 161.5,
(2p). Yellow solid; mp 146e148 ꢀC; IR (KBr) 3410, 2920, 1650, 1597,
160.7, 140.4, 138.0, 137.0, 128.7, 128.3,127.9, 127.5, 119.3, 114.3, 55.4,
43.1; MS (ESI) m/z 309.1 [MþH]þ; HRMS (ESI) calcd for
[C18H16N2O3þH]þ 309.1230, found 309.1234.
1480, 1345, 1257, 1104, 850, 701 cmꢁ1 1H NMR (300 MHz, CDCl3)
;
d
8.19 (s, 1H), 7.89 (s, 1H), 8.09e8.32 (m, 4H), 7.26e7.37 (m, 5H),
4.60 (d, 2H); 13C NMR (75 MHz, CDCl3)
d
165.0, 160.8, 151.6, 148.8,
139.9, 138.3, 128.7, 128.0, 127.8, 127.3, 126.8, 124.9, 42.8; MS (ESI) m/
z 340.1 [MþH]þ; HRMS (ESI) calcd for [C17H13N3O3SþH]þ 340.0750,
found 340.0742.
4.2.24. N-Benzyl-2-p-tolyloxazole-4-carboxamide (4h). White solid;
mp: 137e138 ꢀC; IR (KBr) 3341, 3133, 3038, 2920, 2855, 1655, 1593,
1519, 1500, 1458, 1384, 1325, 1255, 1109, 1060, 828 cmꢁ1 1H NMR
;
(300 MHz, CDCl3)
d
8.24 (s, 1H), 7.91 (d, 2H, J¼8.4 Hz), 7.28e7.39 (m,
4.2.17. Methyl 2-phenyloxazole-4-carboxylate (4a). White solid;
mp: 81e81.5 ꢀC; IR (KBr) 3156, 3103, 3003, 2950, 2855, 1718, 1571,
1442,1317,1258,1204,1143,1127,1057,1001, 780, 713, 691 cmꢁ1; 1H
8H), 4.65(d, 2H, J¼6.0 Hz), 2.41 (s, 3H); 13C NMR (75 MHz, CDCl3)
d
161.7, 160.7, 141.5, 140.6, 138.1, 137.1, 129.6, 128.7, 127.9, 127.6,
126.6, 123.9, 43.1, 21.5; MS (ESI) m/z 293.1 [MþH]þ; HRMS (ESI)
NMR (300 MHz, CDCl3)
d
8.30 (s, 1H), 8.10e8.14 (m, 3H), 7.46e7.50
161.5, 160.8, 127.2,
calcd for [C18H16N2O2þH]þ 293.1281, found 293.1285.
(m, 2H), 3.96 (s, 3H); 13C NMR (75 MHz, CDCl3)
d
142.8, 142.8, 133.4, 130.2, 127.8, 127.8, 125.9, 125.4, 51.2; MS (ESI) m/
z 204.0 [MþH]þ; HRMS (ESI) calcd for [C11H9NO3þH]þ 204.0662,
found 204.0655.
4.2.25. N-Benzyl-2-(4-(trifluoromethyl)phenyl)oxazole-4-
carboxamide (4i). White solid; mp: 117e118 ꢀC; IR (KBr) 3320,
2938, 1654, 1621, 1597, 1525, 1504, 1435, 1415, 1325, 1259, 1171,
1127, 1083, 853, 790 cmꢁ1 1H NMR (300 MHz, CDCl3)
; d 8.32 (s,
4.2.18. Methyl 2-(4-methoxyphenyl)oxazole-4-carboxylate
(4b). White solid; mp: 111e112 ꢀC; IR (KBr) 3162, 3103, 3026,
2956, 2850, 1742, 1616, 1502, 1440, 1323, 1269, 1250, 1129, 1151,
1H), 8.15 (d, 2H, J¼8.4 Hz), 7.73 (d, 2H, J¼8.4 Hz), 7.31e7.39 (m,
6H), 4.67 (d, 2H, J¼6.0 Hz); 13C NMR (75 MHz, CDCl3)
d 160.2,
1123, 1018, 829 cmꢁ1; 1H NMR (300 MHz, CDCl3)
d 8.25 (s, 1H), 8.05
160.0, 141.7, 137.9, 137.7, 132.8, 132.4, 129.7, 128.8, 128.5, 127.9,
127.6, 126.9, 125.9, 125.9, 125.5, 121.9, 43.1; MS (ESI) m/z 347.1
[MþH]þ; HRMS (ESI) calcd for [C18H13F3N2O2þH]þ 347.0999,
found 347.1002.
(d, 2H, J¼7.2 Hz), 6.98 (d, 2H, J¼7.2 Hz), 3.95 (s, 3H), 3.87 (s, 3H); 13C
NMR (75 MHz, CDCl3) d 162.6, 162.0, 161.9, 143.3, 134.2, 128.6, 119.1,
114.2, 55.4, 52.1; MS (ESI) m/z 234.0 [MþH]þ; HRMS (ESI) calcd for
[C12H11NO4þH]þ 234.0759, found 234.0761.
4.2.26. N-Benzyl-2-(4-fluorophenyl)oxazole-4-carboxamide
(4j). White solid; mp: 122e123.5 ꢀC; IR (KBr) 3306, 2944,
1652,1610, 1595, 1520, 1499, 1384, 1325, 1240, 1113, 846, 815, 742,
4.2.19. Methyl 2-(4-ethoxyphenyl)oxazole-4-carboxylate
(4c). White solid; mp: 110e112 ꢀC; IR (KBr) 3144, 2920, 2843,
697 cmꢁ1 1H NMR (300 MHz, CDCl3)
; d 8.26 (s, 1H), 8.02 (t, 2H,
1753, 1615,1500, 1384, 1324, 1259, 1192, 1143, 1118, 1036, 830 cmꢁ1
;
1H NMR (300 MHz, CDCl3)
d
3.09 (t, 3H, J¼6.9 Hz), 3.95 (s, 3H), 4.09
J¼8.7 Hz), 7.30e7.39 (m, 6H), 7.16 (t, 2H, J¼8.7 Hz), 4.65 (d, 2H,
J¼6.0 Hz); 13C NMR (75 MHz, CDCl3)
d 166.1, 162.7,160.6, 160.4,
140.9, 140.9, 137.9,137.2, 128.9, 128.7,128.5,127.9,127.6,122.9, 122.9,
(q, 2H, J¼6.9 Hz), 6.94e8.05 (m, 4H), 8.24 (s, 1H); 13C NMR (75 MHz,
CDCl3) d 175.7, 162.7,161.9, 161.4, 143.3, 128.6, 118.9, 114.7, 63.7, 52.2,