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1H), 7.95 (t, J ¼ 7.6 Hz,1H), 7.67 (d, J ¼ 4.8 Hz, 2H), 7.07 (d, J ¼ 8.0 Hz,
1H). 13C NMR (100 MHz, DMSO-d6) (ppm): 161.3, 160.5, 159.3, 146.9,
142.2, 136.6, 134.9, 133.8, 131.9, 129.7, 128.3, 127.8, 127.0, 124.9,
123.4, 119.8, 114.2, 111.1.
129.9, 125.0, 123.7, 119.1, 118.8, 118.1, 114.8, 109.8, 40.2, 30.2, 20.5,
13.9. IR (KBr): 2947, 2867, 1855, 1386, 759 cmꢂ1; HR-MS: C22H17NO3
calculated: 343.1208, found: 343.1206.
5.1.9.4. N-(20-piperazidine-ethyl)-benzo[k,l]xanthene-3,4-
naphthalimide (13d). Yellow solid, yield: 82%, m.p. 198e200 ꢀC. 1H
NMR (400 MHz, CDCl3eCD3OD) (ppm): 8.58 (d, J ¼ 8.0 Hz, 1H), 8.53
(d, J ¼ 8.4 Hz,1H), 8.08 (d, J ¼ 7.6 Hz,1H), 7.96 (d, J ¼ 7.6 Hz,1H), 7.54
(t, J ¼ 7.2 Hz, 1H), 7.37 (brs, 2H), 7.28 (t, J ¼ 7.6 Hz, 1H), 4.31 (t,
J ¼ 6.8 Hz, 2H), 3.93e3.87 (m, 2H), 3.01 (brs, 4H), 2.74 (brs, 4H). 13C
NMR (100 MHz, CDCl3eCD3OD) (ppm): 164.2, 163.9, 156.1, 151.9,
134.0, 133.9, 133.4, 132.3, 130.0, 125.2, 123.8, 118.9, 118.7, 118.1, 115.0,
110.0, 55.6, 51.5, 44.3, 37.0. IR (KBr): 2921, 2855, 1688, 1660, 1590,
5.1.7. 4-(2-Aminophenoxy)-1,8-naphthalic anhydride (11) [35]
A mixture of compound 10 (0.25 g, 0.0008 mol) and iron powder
(0.12 g, 0.002 mol) was refluxed in glacial acetic acid (10 mL) for 1 h.
The brown solution was cooled and water (30 mL) was added. The
precipitate was filtered and washed with water. Yellow solid, yield:
94%, m.p. 172e174 ꢀC (m.p. 171e172 ꢀC in literature). 1H NMR
(400 MHz, DMSO-d6) (ppm): 8.89 (d, J ¼ 8.4 Hz, 1H), 8.60 (d,
J ¼ 5.2 Hz, 1H), 8.46 (d, J ¼ 8.0 Hz, 1H), 7.96 (t, J ¼ 7.2 Hz, 1H), 7.10 (t,
J ¼ 7.6 Hz, 1H), 7.05 (d, J ¼ 7.6 Hz, 1H), 6.93 (d, J ¼ 8.0 Hz, 1H), 6.84
(d, J ¼ 8.4 Hz, 1H), 6.68 (t, J ¼ 7.6 Hz, 1H), 5.19 (s, 2H). 13C NMR
(100 MHz, DMSO-d6) (ppm): 161.6, 160.7, 160.6, 141.4, 139.6, 135.6,
133.7, 132.0, 130.8, 127.4, 127.4, 123.6, 122.2, 119.2, 117.1, 117.0, 112.0,
109.6.
765 cmꢂ1
399.1576.
. HR-MS: C24H21N3O3 calculated: 399.1583, found:
5.1.10. 4-Phenoxy-3-nitro-dicarboxylic anhydride (14) [23]
A mixture of 4 (9.8 g, 0.030 mol), phenol (1.8 mL, 0.0175 mol)
and sodium hydride (1.3 g, 0.054 mol) was refluxed in pyridine
(220 mL) for 5 h. The solution was concentrated, filtered, and
washed with water. Pale yellow solid, yield: 97%, m.p. 289.0e
289.9 ꢀC (m.p. 287 ꢀC in literature). 1H NMR (400 MHz, DMSO-d6)
(ppm): 8.99 (s, 1H), 8.73 (d, J ¼ 7.2 Hz, 1H), 8.52 (d, J ¼ 8.4 Hz, 1H),
8.04 (t, J ¼ 8.0 Hz, 1H), 7.40 (t, J ¼ 7.6 Hz, 2H), 7.17 (t, J ¼ 7.2 Hz, 1H),
6.99 (d, J ¼ 8.0 Hz, 2H). 13C NMR (100 MHz, DMSO-d6) (ppm): 160.3,
159.5, 158.4, 149.6, 140.7, 135.7, 133.1, 131.4, 130.8, 130.3, 128.0,
126.9, 124.3, 120.9, 118.1, 116.0.
5.1.8. Benzo[k,l]xanthene-3,4-dicarboxylic anhydride (12) [35]
11 (0.5 g, 0.0017 mol) was dissolved in glacial acetic acid (12 mL)
and then hydrochloric acid (1 mL) and sodium nitrite solution
(1.14 g, 0.016 mol in 4 mL water) were added at 0 ꢀC. After 1 h
copper sulfate solution (1.12 g, 0.007 mol in 20 mL water) was
added. The reaction mixture was refluxed further for 0.5 h and
cooled. The precipitate was filtered, washed with water and crys-
tallized from DMF. Yellow solid, yield: 93.2%. M.p. 156e159 ꢀC (m.p.
155e160 ꢀC in literature).
5.1.11. 4-Phenoxy-3-amino-dicarboxylic anhydride (15) [23]
14 (5.24 g, 0.016 mol) was added to SnCl2$2H2O (29 g, 0.129 mol)
in hydrochloric acid (36%,100 mL). The reaction mixture was stirred
at 85 ꢀC for 2 h. Then the reaction was cooled and filtered. The
residue was washed with water and recrystallized from pyridine.
Yellow solid, yield: 79.7%, m.p. 261.2e262.3 ꢀC (m.p. 258e259 ꢀC in
literature). 1H NMR (400 MHz, DMSO-d6) (ppm): 8.25 (s, 1H), 8.17
(d, J ¼ 6.8 Hz, 1H), 7.94 (d, J ¼ 8.0 Hz, 1H), 7.68 (t, J ¼ 7.6 Hz, 1H), 7.33
(t, J ¼ 7.2 Hz, 2H), 7.07 (t, J ¼ 6.0 Hz, 1H), 6.87 (d, J ¼ 7.6 Hz, 2H), 6.02
(s, 2H). 13C NMR (100 MHz, DMSO-d6) (ppm): 161.4, 160.8, 157.6,
141.0, 136.5, 130.4, 128.3, 128.0, 127.5, 127.1, 125.1, 124.3, 123.0, 119.7,
117.0, 115.6.
5.1.9. General procedure for the preparation of 13ae13d
12 (0.29 g, 0.001 mol) was dissolved in 20 mL ethanol. After
adding corresponding primary amine (0.003 mol), the mixture was
stirred and refluxed for 2e3 h, then the solution was evaporated in
vacuum and the residue was purified on silica gel chromatography.
5.1.9.1. N-(N0,N0-dimethylamine-ethyl)-benzo[k,l]xanthene-3,4-
naphthalimide (13a). Yellow solid, yield: 85%, m.p. 191e192 ꢀC. 1H
NMR (400 MHz, CDCl3) (ppm): 8.60 (d, J ¼ 8.0 Hz, 1H), 8.56 (d,
J ¼ 8.0 Hz,1H), 8.04 (d, J ¼ 8.0 Hz,1H), 7.89 (d, J ¼ 7.6 Hz,1H), 7.54 (t,
J ¼ 7.6 Hz,1H), 7.36 (d, J ¼ 8.0 Hz, 2H), 7.26 (d, J ¼ 8.4 Hz,1H), 4.37 (t,
J ¼ 7.2 Hz, 2H), 2.74 (t, J ¼ 7.2 Hz, 2H), 2.44 (s, 6H). 13C NMR
(100 MHz, CDCl3) (ppm): 164.0, 163.7, 155.8, 151.9, 133.8, 133.4,
133.2, 132.1, 130.0, 125.0, 123.7, 119.9, 118.8, 118.1, 114.9, 114.8, 109.9,
5.1.12. Benzo[b]furano[2,1-c] dicarboxylic anhydride (16) [23]
The solution of NaNO2 (0.545 g, 0.008 mol) in concentrated
sulfuric acid (32.7 mL) was added dropwise with glacial acetic acid
(4.87 mL) at ꢂ5 to 0 ꢀC and then added with 15 (2 g, 0.007 mol) in
batches. After 2 h, the solution was added dropwise to the mixed
solution (74 g copper sulfate, 100 mL glacial acetic acid, 800 mL
water) and then continued to reflux for 0.5 h. The resulting sus-
pension was cooled, filtered and washed with water. The solid was
purified on silica gel chromatography (petroleum ether/ethyl ace-
tate, 5:1). Yellow solid, yield: 61%, m.p. 147e149 ꢀC (m.p. 145e
146 ꢀC in literature). 1H NMR (400 MHz, DMSO-d6) (ppm): 9.43 (s,
1H), 8.93 (d, J ¼ 8.4 Hz, 1H), 8.63 (d, J ¼ 7.2 Hz, 1H), 8.52 (d,
J ¼ 7.6 Hz, 1H), 8.09 (t, J ¼ 8.0 Hz, 1H), 7.99 (d, J ¼ 8.4 Hz, 1H), 7.70 (t,
J ¼ 8.0 Hz, 1H), 7.59 (t, J ¼ 7.6 Hz, 1H).
56.9, 45.6, 37.9, 29.7. IR (KBr): 2937, 2770, 1645, 1594, 1380 cmꢂ1
HR-MS: C22H18N2O3 calculated: 358.1317, found: 358.1321.
.
5.1.9.2. N-(N0,N0-dimethylamine-propyl)-benzo[k,l]xanthene-3,4-
naphthalimide (13b). Yellow solid, yield: 78%, m.p. 194e195 ꢀC. 1H
NMR (400 MHz, DMSO-d6) (ppm): 8.31 (d, J ¼ 8.0 Hz, 2H), 8.18 (d,
J ¼ 8.4 Hz, 1H), 8.03 (d, J ¼ 7.6 Hz,1H), 7.59 (t, J ¼ 7.6 Hz, 1H), 7.36 (d,
J ¼ 8.4 Hz, 2H), 7.25 (d, J ¼ 8.4 Hz,1H), 4.05 (t, J ¼ 6.4 Hz, 2H), 3.12 (t,
J ¼ 4.0 Hz, 2H), 2.73 (s, 6H), 2.05 (t, J ¼ 7.6 Hz, 2H). 13C NMR
(100 MHz, DMSO-d6) (ppm): 163.5, 163.2, 155.3, 151.5, 133.7, 133.1,
133.0, 129.4, 125.8, 124.8, 119.5, 118.7, 118.2, 118.1, 116.1, 114.6, 110.3,
54.9, 42.5, 37.4, 23.4. IR (KBr): 2929, 2766, 1588, 1657, 1382,
769 cmꢂ1
372.1473.
; HR-MS: C23H20N2O3 calculated: 372.1474, found
5.1.13. General procedure for the preparation of 17ae17d
16 (0.29 g, 0.001 mol) was dissolved in 20 mL ethanol. After
adding corresponding primary amine (0.003 mol), the mixture was
stirred and refluxed for 2 h. Then the solution was evaporated in
vacuum and the residue was purified on silica gel chromatography.
5.1.9.3. N-(n-butyl)-benzo[k,l]xanthene-3,4-naphthalimide
(13c).
Yellow solid, yield: 75%, m.p. 181e182 ꢀC. 1H NMR (400 MHz, CDCl3)
(ppm): 8.62 (d, J ¼ 7.6 Hz, 1H), 8.58 (d, J ¼ 8.4 Hz, 1H), 8.06 (d,
J ¼ 7.6 Hz, 1H), 7.91 (d, J ¼ 7.2 Hz, 1H), 7.54 (t, J ¼ 7.6 Hz, 1H), 7.35 (t,
J ¼ 8.0 Hz, 2H), 7.27 (d, J ¼ 10.0 Hz, 1H), 4.21 (t, J ¼ 7.2 Hz, 2H), 1.79e
1.71 (m, 2H), 1.53e1.44 (m, 2H), 1.01 (t, J ¼ 6.8 Hz, 3H). 13C NMR
(100 MHz, CDCl3) (ppm): 155.7, 151.9, 133.7, 133.3, 133.1, 132.0,
5.1.13.1. N-(N0,N0-dimethylamine-ethyl)-benzo[b]furano[2,1-c]naph-
thalimide (17a). Yellow solid, yield: 91%, m.p. 156e157 ꢀC. 1H NMR
(400 MHz, CDCl3) (ppm): 9.15 (s, 1H), 8.74 (d, J ¼ 8.4 Hz,1H), 8.67 (d,