PAPER
Heterocyclizations of N-Arylmaleimides and 6-Aminouracils
3165
N-(4-Chlorophenyl)-2,4,7-trioxo-1,2,3,4,5,6,7,8-octahydropyri-
do[2,3-d]pyrimidine-5-carboxamide (3b)
Yellow solid; mp >300 °C.
1,3-Dimethyl-2,4,7-trioxo-N-phenyl-1,2,3,4,5,6,7,8-octahydro-
pyrido[2,3-d]pyrimidine-5-carboxamide (3f)
Colorless solid; mp 275–276 °C.
2
2
1H NMR (200 MHz, DMSO-d6): d = 2.59 (dd, JAB = 15.7 Hz,
1H NMR (200 MHz, DMSO-d6): d = 2.62 (dd, JAB = 16.3 Hz,
3JAX = 1.3 Hz, 1 H, 6-Ha), 2.90 (dd, 3JBX = 7.7 Hz, 1 H, 6-Hb), 3.19
(s, 3 H, CH3), 3.38 (s, 3 H, CH3), 3.93 (dd, 1 H, 5-Hx), 7.00–7.55 (m,
5 Harom), 9.86 (br s, 1 H, NH), 10.53 (br s, 1 H, NHpyr).
3JAX = 1.3 Hz, 1 H, 6-Ha), 2.93 (dd, 3JBX = 7.5 Hz, 1 H, 6-Hb), 3.80
(dd, 1 H, 5-Hx), 7.32–7.60 (m, 4 Harom), 10.04 (br s, 1 H, NH), 9.6–
10.4 (br s, 2 H, NH), 11.03 (br s, 1 H, NHpyr).
13C NMR (50 MHz, DMSO-d6): d = 170.2, 168.5, 163.0, 149.6,
147.1, 138.4, 128.3, 123.1, 119.1, 85.1, 35.6, 32.9.
13C NMR (50 MHz, DMSO-d6): d = 170.1, 169.7, 161.1, 150.5,
147.3, 138.4, 128.3, 123.2, 119.3, 86.8, 36.5, 33.0, 30.0, 27.5.
MS (EI, 70 eV): m/z (%) = 335 (2, [M+ – 1]), 333 (2, [M+ – 1]), 179
MS (EI, 70 eV): m/z (%) = 327 (2), 328 (3, [M+ – 1]), 208 (6).
(29), 178 (67), 150 (59), 149 (32).
Anal. Calcd for C16H16N4O4: C, 58.53; H, 4.91; N, 17.06. Found: C,
58.5; H, 5.1; N, 17.0.
Anal. Calcd for C14H11ClN4O4: C, 50.24; H, 3.31; N, 16.74. Found:
C, 50.1; H, 3.3; N, 16.8.
N-(2-Methoxyphenyl)-1,3-dimethyl-2,4,7-trioxo-1,2,3,4,5,6,7,8-
octahydropyrido[2,3-d]pyrimidine-5-carboxamide (3g)
Colorless solid; mp 265–266 °C.
N-(2,4-Dimethylphenyl)-2,4,7-trioxo-1,2,3,4,5,6,7,8-octahydro-
pyrido[2,3-d]pyrimidine-5-carboxamide (3c)
Colorless solid; mp 275–276 °C.
1H NMR (200 MHz, DMSO-d6): d = 2.11 (s, 3 H, CH3), 2.22 (s, 3
H, CH3), 2.65 (dd, 2JAB = 16.4 Hz, 3JAX = 1.3 Hz, 1 H, 6-Ha), 2.83
(dd, 3JBX = 7.6 Hz, 1 H, 6-Hb), 3.87 (dd, 1 H, 5-Hx), 6.9–7.44 (m, 3
Harom), 9.04 (br s, 1 H, NH), 9.7–10.3 (br s, 2 H, NH), 11.09 (br s, 1
H, NHpyr).
2
1H NMR (200 MHz, DMSO-d6): d = 2.67 (dd, JAB = 16.4 Hz,
3JAX = 3.3 Hz, 1 H, 6-Ha), 2.75 (dd, 3JBX = 5.6 Hz, 1 H, 6-Hb), 3.24
(s, 3 H, CH3), 3.37 (s, 3 H, CH3), 3.83 (s, 3 H, CH3O), 4.06 (dd, 1
H, 5-Hx), 6.85–8.05 (m, 4 Harom), 9.16 (br s, 1 H, NH), 10.54 (br s,
1 H, NHpyr).
13C NMR (50 MHz, DMSO-d6): d = 169.7, 169.6, 161.4, 150.3,
148.4, 146.8, 127.5, 123.5, 120.2, 119.7, 111.2, 86.5, 55.8, 35.9,
31.9, 30.0, 27.5.
MS (EI, 70 eV): m/z (%) = 358 (3), 357 (18, [M+ – 1]), 208 (7), 207
(45), 206 (100), 149 (16), 148 (19).
13C NMR (50 MHz, DMSO-d6): d = 169.9, 168.7, 163.4, 149.8,
147.2, 133.5, 133.4, 130.4, 129.6, 126.1, 122.9, 85.1, 35.0, 32.5,
20.0, 17.0.
MS (EI, 70 eV): m/z (%) = 327 (2, [M+ – 1]), 326 (3, [M+ – 2]), 179
(33), 178 (100), 177 (74), 150 (73), 149 (60).
Anal. Calcd for C17H18N4O5: C, 56.98; H, 5.06; N, 15.63. Found: C,
57.1; H, 4.9; N, 15.7.
Anal. Calcd for C16H16N4O4: C, 58.53; H, 4.91; N, 17.06. Found: C,
58.6; H, 5.1; N, 17.0.
N-(2,4-Dimethylphenyl)-1,3-dimethyl-2,4,7-trioxo-
1,2,3,4,5,6,7,8-octahydropyrido[2,3-d]pyrimidine-5-carbox-
amide (3h)
N-(3-Chloro-4-methoxyphenyl)-2,4,7-trioxo-1,2,3,4,5,6,7,8-oc-
tahydropyrido[2,3-d]pyrimidine-5-carboxamide (3d)
Yellow solid; mp >300 °C.
Colorless solid; mp 269–270 °C.
2
1H NMR (200 MHz, DMSO-d6): d = 2.58 (dd, JAB = 17.2 Hz,
1H NMR (200 MHz, DMSO-d6): d = 2.11 (s, 3 H, CH3), 2.23 (s, 3
H, CH3), 2.70 (dd, 2JAB = 16.0 Hz, 3JAX = 1.3 Hz, 1 H, 6-Ha), 2.84
(dd, 3JBX = 7.2 Hz, 1 H, 6-Hb), 3.22 (s, 3 H, CH3), 3.37 (s, 3 H, CH3),
3.95 (dd, 1 H, 5-Hx), 6.9–7.4 (m, 3 Harom), 9.0 (br s, 1 H, NH), 10.5
(br s, 1 H, NHpyr).
13C NMR (50 MHz, DMSO-d6): d = 169.7, 169.6, 161.28, 161.27,
150.4, 147.1, 133.4, 130.4, 129.7, 126.1, 123.0, 86.8, 35.8, 32.6,
30.0, 27.4, 20.0, 17.0.
3JAX = 1.3 Hz, 1 H, 6-Ha), 2.92 (dd, 3JBX = 8.0 Hz, 1 H, 6-Hb), 3.76
(dd, 1 H, 5-Hx), 3.80 (s, 3 H, CH3O), 7.06–7.72 (m, 3 Harom), 9.91
(br s, 1 H, NH), 9.7–10.4 (br s, 2 H, NH), 11.0 (br s, 1 H, NHpyr).
13C NMR (50 MHz, DMSO-d6): d = 170.1, 168.8, 163.5, 149.8,
148.6, 145.5, 136.1, 121.0, 120.6, 119.3, 113.0, 85.3, 55.1, 35.3,
32.6.
MS (EI, 70 eV): m/z (%) = 364 (2, [M+]), 180 (27), 142 (100), 114
(50).
MS (EI, 70 eV): m/z (%) = 356 (2), 355 (3, [M+ – 1]), 207 (61), 206
(100), 149 (14), 148 (13).
Anal. Calcd for C15H13ClN4O5: C, 49.39; H, 3.59; N, 15.36. Found:
C, 49.4; H, 3.6; N, 15.2.
Anal. Calcd for C18H20N4O4 (%): C, 60.66; H, 5.66; N, 15.72.
Found: C, 60.7; H, 5.6; N, 15.8.
2,4,7-Trioxo-N-[4-(trifluoromethyl)phenyl]-1,2,3,4,5,6,7,8-oc-
tahydropyrido[2,3-d]pyrimidine-5-carboxamide (3e)
Colorless solid; mp >300 °C.
N-(4-Methoxyphenyl)-1,3-dimethyl-2,4,7-trioxo-1,2,3,4,5,6,7,8-
octahydropyrido[2,3-d]pyrimidine-5-carboxamide (3i)
Colorless solid; mp 279–280 °C.
2
1H NMR (200 MHz, DMSO-d6): d = 2.63 (dd, JAB = 17.0 Hz,
3JAX = 1.3 Hz, 1 H, 6-Ha), 2.95 (dd, 3JBX = 8.2 Hz, 1 H, 6-Hb), 3.84
(dd, 1 H, 5-Hx), 7.63–7.78 (m, 4 Harom), 10.29 (br s, 1 H, NH), 9.8–
10.5 (br s, 2 H, NH), 11.04 (br s, 1 H, NHpyr).
1H NMR (200 MHz DMSO-d6): d = 2.61 (dd, JAB = 16.3 Hz,
2
3JAX = 1.4 Hz, 1 H, 6-Ha), 2.89 (dd, 3JBX = 7.6 Hz, 1 H, 6-Hb), 3.19
(s, 3 H, CH3), 3.37 (s, 3 H, CH3), 3.70 (s, 3 H, CH3O), 3.88 (dd, 1
H, 5-Hx), 6.83–7.47 (m, 4 Harom), 9.71 (br s, 1 H, NH), 10.54 (br s,
1 H, NHpyr).
13C NMR (50 MHz, DMSO-d6): d = 171.0, 168.4, 163.0, 149.7,
147.4, 142.0, 126.6, 125.0 (1 C, q, 1JCF = 271.2 Hz, CF3), 124.4 (1
C, q, 2JCF = 32.2 Hz, CCF3), 120.1, 85.8, 36.8, 33.8.
MS (EI, 70 eV): m/z (%) = 368 (2, [M+]), 367 (3), 180 (25), 179
(100), 150 (38).
13C NMR (50 MHz, DMSO-d6): d = 169.65, 169.6, 161.0, 155.3,
150.5, 147.2, 131.6, 120.9, 113.7, 86.9, 55.0, 36.3, 33.1, 30.0, 27.4.
MS (EI, 70 eV): m/z (%) = 358 (7), 357 (30, [M+ – 1]), 356 (28), 208
(5), 207 (56), 206 (100), 149 (51), 148 (64).
Anal. Calcd for C15H11F3N4O4: C, 48.92; H, 3.01; N, 15.21. Found:
C, 49.1; H, 3.0; N, 15.3.
Anal. Calcd for C17H18N4O5: C, 56.98; H, 5.06; N, 15.63. Found: C,
57.1; H, 5.1; N, 15.6.
Synthesis 2011, No. 19, 3161–3167 © Thieme Stuttgart · New York