Med Chem Res (2011) 20:854–864
861
8-Amino-7-phenyl-7,11-dihydro-10H-benzo[7,8]chromeno
[2,3-d]pyrimidin-10-one (7c) 182–185°C (ethanol),
Brown solid, Yield 55%, IR (KBr) m (cm-1): 3448 (–NH
stretching at NH2), 3311 (–NH stretching at pyrimidine
ring), 1657 ([C=O stretching), 1605, 1510 (–NH bending
at NH2), 1575 (C=N pyrimidine ring), 1444, 1416 (C–N at
Calcd. for C20H13N3O2: C, 73.38; H, 4.00; N, 12.84;
Found: C, 73.43; H, 3.95; N, 12.90.
General preparation of 4-amino-5-phenyl-1,5-dihydro-
2H-substitutedchromeno[2,3-d]pyrimidin-2-one 7(a–e)
1
pyrimidine ring), 1264 (C–O–C at pyran ring); H-NMR
Mixture of compound 4(a–e) (2 mmol) and urea (2 mmol)
with catalytic amount of sodium ethoxide in ethanol was
refluxed on sand bath for 6–7 h (monitored by TLC tolu-
ene:methanol; (7:3)). After completion of the reaction, the
reaction mixture was poured in crushed ice and neutralized
with diluted hydrochloric acid. The precipitated product
was collected by the filtration and washed with water. The
crude product was purified by crystallization from absolute
ethanol and purified by column chromatography (silica gel)
using hexane and ethylacetate (2:5) as the eluent to afford
the corresponding product. 7(a–e).
(300MHz, CDCl3) d (ppm): 4.75 (s, 1H, pyran –CH), 8.05
(s, 2H, –NH2), 8.16 (s, 1H, –NH at pyrimidine ring),
7.03–7.89 (m, 11H, Ar–H); m/z: 341.12 (100.0%), 342.12
(23.0%), 343.12 (3.1%), 342.11 (1.1%); 13C-NMR
(300MHz, CDCl3) d (ppm): 136.0 and 151.0 (C–O–C at
pyran ring), 32.7 (–CH at pyran ring), 164.6 (C–NH2),
148.4 ([C=O), 123.2, 122.7, 123.8, 123.6, 124.2, 125.8,
126.9, 127.4, 128.6, 129.9, 130.4, 130.2 (aromatic car-
bons); Anal. Calcd. for C21H15N3O2: C, 73.89; H, 4.43; N,
12.31; Found: C, 73.85; H, 4.48; N, 12.36.
11-Amino-12-phenyl-8,12-dihydro-9H-benzo[5,6]chromeno
[2,3-d]pyrimidin-9-one (7d) 240–244°C (ethanol), Brown
solid, Yield 74%, IR (KBr) m (cm-1): 3446 (–NH stretching
at NH2), 3322 (–NH stretching at pyrimidine ring), 1643
([C=O), 1615, 1505 (–NH bending at NH2), 1579 (C=N at
pyrimidine ring), 1452, 1419 (C–N at pyrimidine ring),
4-Amino-5-phenyl-1,5-dihydro-2H-chromeno[2,3-d]pyrim-
idin-2-one (7a) 178–182°C (ethanol), Yellow solid, Yield
58%, IR (KBr) m (cm-1): 3446 (–NH stretching at NH2),
3301 (–NH stretching at pyrimidine ring), 1653 ([C=O),
1605, 1509 (–NH bending at NH2), 1579 (C=N at pyrim-
idine ring), 1454, 1400 (C–N at pyrimidine ring), 1448,
1
1
1267 (C–O–C at pyran ring); H-NMR (300MHz, CDCl3)
1260 (C–O–C at pyran ring); H-NMR (300MHz, CDCl3)
d (ppm): 4.78 (s, 1H, pyran –CH), 7.95 (s, 2H, –NH2), 8.05
(s, 1H, –NH at pyrimidine ring), 6.89–7.35 (m, 11H, Ar–
H); m/z: 341.12 (100.0%), 342.12 (23.0%), 343.12 (3.1%),
342.11 (1.1%); 13C-NMR (300MHz, CDCl3) d (ppm):
136.0 and 151.0 (C–O–C at pyran ring), 32.7 (–CH at pyran
ring), 164.6 (C–NH2), 158.4 ([C=O), 123.2, 122.7, 123.8,
123.6, 124.2, 125.8, 126.9, 127.4, 128.6, 129.9, 130.4,
130.2 (aromatic carbons); Anal. Calcd. for C21H15N3O2: C,
73.89; H, 4.43; N, 12.31; Found: C, 73.93; H, 4.38; N,
12.28.
d (ppm): 4.84 (s, 1H, pyran –CH), 8.15 (s, 2H, –NH2), 8.21
(s, 1H, –NH at pyrimidine ring), 6.78–7.45 (m, 9H, Ar–H);
m/z: 291.10 (100.0%), 292.10 (19.6%), 293.11 (2.0%);
13C-NMR (300MHz, CDCl3) d (ppm): 150.3 and 148.9 (C–
O–C at pyran ring), 33.8 (–CH at pyran ring), 163.3 (C–
NH2), 162.5 ([C=O), 122.5, 122.5, 123.6, 124.2, 125.3,
127.9, 128.4, 129.2, 130.3 131.0 (aromatic carbons); Anal.
Calcd. for C17H13N3O2: C, 70.09; H, 4.50; N, 14.42;
Found: C, 70.14; H, 4.46; N, 14.48.
4-Amino-8-hydroxy-5-phenyl-1,5-dihydro-2H-chromeno
[2,3-d]pyrimidin-2-one (7b) 190–193°C (ethanol),
Orange solid, Yield 61%, IR (KBr) m (cm-1): 3450 (–NH
stretching at NH2), 3306 (–NH stretching at pyrimidine
ring), 3215 (–OH), 1667 ([C=O), 1613, 1509 (–NH
stretching at NH2), 1580 (C=N pyrimidine ring), 1456,
1407 (C=N pyrimidine ring), 1437, 1265 (C–O–C at pyran
8-Amino-7-phenyl-7,11-dihydro-10H-pyrimido[50,40:5,6]pyr-
ano[3,2-h]quinolin-10-one (7e) 188–190°C (ethanol),
Green solid, Yield 78%, IR (KBr) m (cm-1): 3446 (–NH
stretching at NH2), 3311 (–NH stretching at pyrimidine
ring), 1649 ([C=O stretching), 1609, 1511 (–NH bending
at NH2), 1580(C=N Pyrimidine ring), 1454, 1405 (C–N at
pyrimidine ring), 1250 (C–O–C); 1H-NMR (300MHz,
CDCl3) d (ppm): 4.84 (s, 1H, pyran –CH), 8.24 (s, 2H,
–NH2), 8.11 (s, 1H, –NH at pyrimidine ring), 6.83–7.64 (m,
7H, Ar–H), 7.33–7.57 (m, 3H, Ar–H at pyridine ring); m/z:
342.11 (100.0%), 343.12 (21.9%), 344.12 (2.7%), 343.11
(1.5%); 13C-NMR (300MHz, CDCl3) d (ppm): 136.9 and
151.4 (C–O–C at pyran ring) 34.8 (–CH at pyran ring),
164.8 (C–NH2), 160.9 (C=0), 119.6, 128.0, 135.8, 137.2
(carbons at pyridine ring), 150.0 (C=N at pyridine ring),
128.6, 131.2, 131.8, 132.9, 133.6, 134.9, 135.4, 136.2
(aromatic carbons); Anal. Calcd. for C20H14N4O2: C,
1
ring); H-NMR (300MHz, CDCl3) d (ppm): 4.76 (s, 1H,
pyran –CH), 8.0 (s, 2H, –NH2), 8.12 (s, 1H, –NH at
pyrimidine ring), 6.85–7.30 (m, 8H, Ar–H), 9.09 (s, 1H,
–OH); m/z: 307.10 (100.0%), 308.10 (18.7%), 309.10
(2.4%), 308.09 (1.1%); 13C-NMR (300MHz, CDCl3) d
(ppm): 154.5 and 136.2 (C–O–C at pyran ring), 34.4 (–CH
at pyran ring), 164.6 (C–NH2), 161.3 ([C=O), 162.8 (C–
OH), 100.2, 110.5, 111.5, 123.6, 123.2, 125.3, 125.9,
128.4, 129.2, 130.3, 131.0 (aromatic carbons); Anal. Calcd.
for C17H13N3O3: C, 66.44; H, 4.26; N, 13.67; Found: C,
66.38; H, 4.31; N, 13.72.
123