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8.23 (m, 2H), 8.17 (t, 1H, J1 = 8.00 Hz, J2 = 8.00 Hz),
7.93–7.90 (m, 2H). HRMS: C18H9N3O2 calculated:
299.0695. Found: 299.0696. IR (KBr), cmꢀ1: 3407,
2919, 1521, 1315, 1190, 1085.
(t, 1H, J1 = 8.40 Hz, J2 = 7.20 Hz), 6.88 (t, 1H, J1 = 6.40
Hz, J2 = 8.00 Hz), 3.56 (t, 2H, J1 = 3.20 Hz, J2 = 6.40 Hz,
–NCH2CH2N(CH3)2), 2.37 (s, 2H, –NCH2CH2N(CH3)2),
2.77 (s, 6H, –NCH2CH2N(CH3)2). HRMS: C22H19N5O2
calculated: 385.1539. Found: 385.1551. IR (KBr), cmꢀ1
:
4.2.3. Synthesis of 9-nitro-acenaphtho[1,2-b]quinoxaline
(A3). The compound was prepared on a 0.1 mmol scale
from acenaphthene quinone and 4-nitro-o-phenylenedi-
amine as described for A1 and crystallized in DMF/H2O
to yield the desired compound A3. Yield 80%.
Mp > 300 ꢁC. 1H NMR (400 MHz, DMSO-d6), d (ppm),
8.99 (d, 1H, J = 2.40 Hz), 8.57–8.52 (m, 3H), 8.44–8.39
(m, 3H), 8.02 (t, 2H, J1 = 8.00 Hz, J2 = 7.20 Hz). HRMS:
C18H9N3O2 calculated: 299.0695. Found: 299.0694. IR
(KBr), cmꢀ1: 3072, 2919, 1526, 1339, 1071.
3339, 2910, 1602, 1521, 1339, 1071.
4.2.8. Synthesis of 6-nitroquinoxaline (A7). To 40% oxal-
aldehyde (5 ml) in MeCN (50 ml) was added 4-nitro-o-
phenylenediamine (4.0 g) at 50 ꢁC slowly. The mixture
was kept stirring for 15 h and cooled down, diluted with
H2O (150 ml) to afford brown precipitate, which was
chromatographed over silica gel column using ethylace-
tate/petroleum ether (v/v) 5:1 as eluent to yield the
desired compound A7. Yield 85%. Mp 174 ꢁC. 1H
NMR (400 MHz, acetone-d6), d (ppm), 9.15 (s, 2H,
–NCH@CHN), 8.95 (d, 1H, J = 2.80 Hz), 8.64–8.61
(M, 1H), 8.37 (t, 1H, J1 = 4.00 Hz, J2 = 8.80 Hz). HRMS:
C8H5N3O2 calculated: 175.0382. Found: 175.0378. IR
(KBr), cmꢀ1: 3368, 3053, 1521, 1344, 1071, 1023.
4.2.4. Synthesis of 3-nitro-acenaphtho[1,2-b]quinoxaline-
9-ylamine (A6). The compound was prepared on a
0.1 mmol scale from 3-aminoacenaphthene quinone and
4-amino-o-phenylenediamine as described for A1 and
crystallized in DMF/H2O to yield the desired compound
A6. Yield 80%. Mp > 300 ꢁC. 1H NMR (400 MHz,
DMSO-d6), d (ppm), 8.28 (d, 1H, J = 1.2 Hz), 8.21 (d,
1H, J = 8.80 Hz), 8.16 (d, 1H, J = 8.40 Hz), 7.92–7.89
(m, 2H), 7.34–7.29 (m, 2H). MS-EI: [M]+ (269.0 m/z).
IR (KBr), cmꢀ1: 3407, 2919, 1631, 1578, 1382, 1099.
4.2.9. Synthesis of 6-aminoquinoxaline (A8). The com-
pound was prepared on a 0.1 mmol scale from A7. To
compound A7 3.30 g (10 mmol) in concentrated hydro-
chloric acid (25 ml), SnCl2 40 mmol was added and the
mixture was stirred for 4 h at 80 ꢁC and then allowed to
cool. The brown solid was precipitated and filtered, and
chromatographed over silica gel column using ethylace-
tate/petroleum ether (v/v) 2:1 as eluent to yield the desired
compound A8. Yield 67%. Mp 157 ꢁC. 1H NMR
4.2.5. Synthesis of 3-bromo-9-nitro-acenaphtho[1,2-b]quin-
oxaline (B). The compound was prepared on a 0.1 mmol
scale from 3-bromoacenaphthene quinone and 4-nitro-
o-phenylenediamine as described for A1 and crystallized
in DMF/H2O to yield the desired compound B. Yield
80%. MS-EI: [M]+ ( 377.0 m/z).
(400 MHz, acetone-d6),
d
(ppm), 8.60 (d, 1H,
J = 2.00 Hz), 8.48 (d, 1H, J = 2.00 Hz), 7.77 (d, 1H,
J = 9.2 Hz), 7.35–7.32 (m, 1H), 7.09 (d, 1H, J = 2.4 Hz),
5.53 (s, 2H, –NH2). HRMS: C8H7N3 calculated:
145.0640. Found: 145.0631. IR (KBr), cmꢀ1: 3395,
3310, 3190, 1648, 1616, 1505, 1310, 1032.
4.2.6. Synthesis of 3-(4-methyl-piperazin-1-yl)-9-nitro-ace-
naphtho[1,2-b]quinoxaline (A4). To 4-methyl-piperazine
2.21 g (10 mmol) in hot DMF (60 ml), 3-bromo-9-nitro-
acenaphtho[1,2-b]quinoxaline 1.25 g (11 mmol) was
added and the mixture was refluxed for 5 h and then al-
lowed to cool in water. A brown solid was precipitated
and filtered, and chromatographed over silica gel column
using CH2Cl2/methanol (v/v) 4:1 as eluent to yield the de-
sired compound A4. Yield 50%. Mp > 300 ꢁC. 1H NMR
(400 MHz, acetone-d6), d (ppm), 8.95 (d, 1H, J =
2.40 Hz), 8.56–8.50 (m, 2H), 8.46 (d, 1H, J = 8.40 Hz),
8.41 (d, 1H, J = 8.00 Hz), 8.38 (d, 1H, J = 9.20 Hz), 7.96
(t, 1H, J1 = 7.80 Hz, J2 = 7.80 Hz), 7.44 (d, 1H,
J = 8.00 Hz), 3.41 (s, 4H, –N(CH2CH2)2NCH3), 2.77 (s,
4H, –N(CH2CH2)2NCH3), 2.41 (s, 3H, –N(CH2CH2)2
NCH3). HRMS: C23H19N5O2 calculated: 397.1539.
Found: 397.1539. IR (KBr), cmꢀ1: 3436, 2947, 1612,
1492, 1432, 1349, 1229, 1006.
4.2.10. Synthesis of acenaphtho[1,2-b]quinoxaline-3,9-
diamine (A9). The compound was prepared on a
0.1 mmol scale from A1 as described for A8 to yield
the desired compound A9. Yield 40%. Mp > 300 ꢁC.
1H NMR (400 MHz, DMSO-d6), d (ppm), 8.36 (d, 1H,
J = 8.40 Hz), 8.25 (d, 1H, J = 6.80 Hz), 8.09 (d, 1H,
J = 7.60 Hz), 7.84 (d, 1H, J = 9.2 Hz), 7.74 (t, 1H,
J1 = 7.20 Hz, J2 = 8.00 Hz), 7.21–7.19 (m, 2H), 7.00 (d,
1H, J = 8.00 Hz). MS-EI: [M]+ (284.1 m/z). IR (KBr),
cmꢀ1: 3311, 2919, 1631, 1574, 1377, 1099.
4.2.11. Synthesis of acenaphtho[1,2-b]quinoxaline-3-yla-
mine (A10). The compound was prepared on a 0.1 mmol
scale from A2 as described for A8 to yield the desired com-
pound A10. Yield 50%. Mp > 300 ꢁC. 1H NMR
(400 MHz, acetone-d6), d (ppm), 8.49 (d, 1H, J = 8.40
Hz), 8.17 (d, 1H, J = 6.80 Hz), 7.83 (t, 1H, J1 = 7.60 Hz,
J2 = 8.00 Hz), 7.79–7.71 (m, 2H), 7.07 (d, 1H,
J = 8.00 Hz), 6.51 (s, 2H, –NH2). HRMS: C18H11N3 cal-
4.2.7. Synthesis of N,N-dimethyl-N0-(9-nitro-acenaph-
tho[1,2-b]quinoxalin-3-yl)-ethane-1,2-diamine (A5). The
compound was prepared on a 0.1 mmol scale from 3-bro-
mo-9-nitro-acenaphtho[1,2-b]quinoxaline and N,N-di-
methyl-ethane-1,2-diamine as described for A4 to yield
culated: 269.0953. Found: 269.0968. IR (KBr), cmꢀ1
3445, 3148, 2919, 1598, 1406, 1272, 1085.
:
1
the desired compound A5. Yield 40%. Mp > 300 ꢁC. H
NMR (400 MHz, DMSO-d6), d (ppm), 8.85 (dd, 1H,
J1 = 2.40 Hz, J2 = 2.40 Hz, J3 = 24.00 Hz), 8.62 (m,
1H), 8.48–8.38 (m, 2H), 8.29 (t, 1H, J1 = 10.00 Hz, J2 =
9.20 Hz), 8.22 (t, 1H, J1 = 9.60 Hz, J2 = 9.20 Hz), 7.84
4.2.12. Synthesis of acenaphtho[1,2-b]quinoxaline-9-yla-
mine (A11). The compound was prepared on a 0.1 mmol
scale from A3 as described for A8 to yield the desired
compound A11. Yield 50%. Mp > 300 ꢁC. 1H NMR