Medicinal Chemistry Research
NMR (300 Mhz, DMSO-d , ppm) δ 0.93 (3H, d, J =
2-[2-(4-(Morpholine-4-yl)benzylidene)hydrazineyl]quinoxa-
line (5h) Yield 67%, m.p. 258.3–260.1 °C. IR νmax (cm ):
6
−
1
6
.4 Hz, CH ), 1.13–1.26 (2H, m, piperidine-H), 1.49–1.57
3
(
1H, m, piperidine-H), 1.69 (2H, d, J = 12.6 Hz, piperidine-
H), 2.73 (1H, t, J = 12.4 Hz, piperidine-H), 3.79 (2H, d, J =
2.8 Hz, piperidine-H), 6.96 (2H, d, J = 8.9 Hz, 1,4-dis-
ubstituted benzene), 7.42–7.47 (1H, m, quinoxaline), 7.57
2H, d, J = 9.0 Hz, 1,4-disubstituted benzene), 7.64–7.65
2H, m, quinoxaline), 7.88 (1H, d, J = 8.1 Hz, quinoxaline),
3207 (N–H) 3084 (aromatic C–H), 2993 (aliphatic C–H),
1
1612–1492 (C=N, C=C), 1309–1111 (C–N, C–O).
H
1
NMR (300 Mhz, DMSO-d , ppm) δ 3.20 (4H, t, J = 4.7 Hz,
6
morpholine-H), 3.75 (4H, t, J = 5.0 Hz, morpholine-H),
7.00 (2H, d, J = 9.0 Hz, 1,4-disubstituted benzene),
7.43–7.48 (1H, m, quinoxaline), 7.60–7.65 (2H, m, qui-
noxaline), 7.89 (1H, d, J = 8.3 Hz, 1,4-disubstituted benzene),
8.05 (1H, s, quinoxaline), 9.04 (1H, s, N=CH), 11.47 (1H, s,
(
(
8
.02 (1H, s, quinoxaline), 9.03 (1H, s, N=CH), 11.42 (1H, s,
1
3
NH). C NMR (75 MHz, DMSO-d , ppm) δ 22.23 (CH ),
6
3
13
3
1
1
3
0.71, 33.74, 48.40, 115.34, 124.48, 125.12, 126.43,
NH). C NMR (75 MHz, DMSO-d , ppm) δ 48.12, 66.45,
6
28.18, 129.20, 130.67, 136.96, 138.14, 141.63, 143.06,
115.02, 125.20, 125.61, 126.46, 128.11, 129.21, 130.69,
+
50.83, 152.19. HRMS (m/z): [M+H] calcd for C H N :
136.96, 138.18, 141.60, 142.84, 150.83, 152.14. HRMS (m/z):
21
23
5
+
46.2026; found: 346.2011.
[M+H] calcd for C H N O: 334.1662; found: 334.1646.
1
9 19 5
2
-[2-(4-(3,5-Dimethylpiperidin-1-yl)benzylidene)hydrazi-
2-[2-(4-(4-Methylpiperazin-1-yl)benzylidene)hydrazineyl]
neyl]quinoxaline (5f) Yield 66%, m.p. 191.1–193.6 °C. IR
νmax (cm ): 3201 (N–H) 3055 (aromatic C–H), 2989 (ali-
quinoxaline (5i) Yield 60%, m.p. 221.9–224.3 °C. IR ν
(cm ): 3207 (N–H) 3057 (aromatic C–H), 2926 (aliphatic
C–H), 1577–1481 (C=N, C=C), 1246–1132 (C–N). H
max
−
1
−1
1
phatic C–H), 1614–1456 (C=N, C=C), 1342–1105 (C–N).
1
H NMR (300 Mhz, DMSO-d , ppm) δ 0.66–0.78 (1H, m,
NMR (300 Mhz, DMSO-d , ppm) δ 2.22 (3H, s, CH ), 2.45
6
6
3
piperidine-H), 0.93 (6H, d, J = 6.5 Hz, CH ), 1.61–1.78
(4H, t, J = 4.9 Hz, piperazine-H), 3.23 (4H, t, J = 4.7 Hz,
piperazine-H), 6.98 (2H, d, J = 8.9 Hz, 1,4-disubstituted
benzene), 7.42–7.48 (1H, m, quinoxaline), 7.59 (2H, d, J =
8.9 Hz, 1,4-disubstituted benzene), 7.64–7.65 (2H, m, qui-
noxaline), 7.88 (1H, d, J = 8.1 Hz, quinoxaline), 8.03 (1H, s,
3
(
3H, m, piperidine-H), 2.25 (2H, t, J = 11.7 Hz, piperidine-
H), 3.77 (2H, d, J = 12.3 Hz, piperidine-H), 6.96 (2H, d, J =
.7 Hz, 1,4-disubstituted benzene), 7.42–7.47 (1H, m, qui-
8
noxaline), 7.56 (2H, d, J = 8.8 Hz, 1,4-disubstituted ben-
zene), 7.63–7.65 (2H, m, quinoxaline), 7.88 (1H, d, J =
13
quinoxaline), 9.04 (1H, s, N=CH), 11.45 (1H, s, NH).
C
8
.1 Hz, quinoxaline), 8.02 (1H, s, quinoxaline), 9.03 (1H, s,
NMR (75 MHz, DMSO-d , ppm) δ 46.21 (CH ), 47.74, 54.91,
6
3
13
N=CH), 11.42 (1H, s, NH). C NMR (75 MHz, DMSO-d6,
ppm) δ 19.60 (CH ), 27.23, 30.50, 42.29, 55.45, 115.18,
115.18, 125.14, 125.17, 126.43, 128.11, 129.21, 130.68,
136.97, 138.16, 141.60, 142.94, 150.82, 152.04. HRMS (m/z):
3
+
1
24.25, 125.11, 126.42, 128.24, 129.20, 130.66, 136.95,
[M+H] calcd for C H N : 347.1979; found: 347.1973.
2
0 22 6
1
38.14, 141.64, 143.10, 150.83, 151.83. HRMS (m/z):
+
[
M+H] calcd for C H25l5: 360.2183; found: 360.2167.
2-[2-(4-(4-Ethylpiperazin-1-yl)benzylidene)hydrazineyl]qui-
22
noxaline (5j) Yield 69%, m.p. 212.0–213.9 °C. IR ν
(cm ): 3167 (N–H) 3057 (aromatic C–H), 2967 (aliphatic
C–H), 1612–1489 (C=N, C=C), 1244–1128 (C–N). H
max
−
1
2
-[2-(4-(4-Benzylpiperidin-1-yl)benzylidene)hydrazineyl]
1
quinoxaline (5g) Yield 78%, m.p. 248.9–251.1 °C. IR ν
max
−
1
(
cm ): 3213 (N–H) 3082 (aromatic C–H), 2967 (aliphatic
NMR (300 Mhz, DMSO-d , ppm) δ 1.02 (3H, t, J = 7.1 Hz,
6
1
C–H), 1612–1492 (C=N, C=C), 1307–1099 (C–N). H
CH ), 2.35 (2H, q, J = 7.2 Hz, CH ), 2.46–2.49 (4H, m,
3
2
NMR (300 Mhz, DMSO-d , ppm) δ 1.21–1.32 (2H, m,
piperidine-H), 1.63–1.74 (3H, m, piperidine-H), 2.55 (2H,
piperazine-H), 3.21 (4H, t, J = 4.9 Hz, piperazine-H), 6.97
(2H, d, J = 8.7 Hz, 1,4-disubstituted benzene), 7.42–7.47
(1H, m, quinoxaline), 7.59 (2H, d, J = 8.7 Hz, 1,4-dis-
ubstituted benzene), 7.64–7.65 (2H, m, quinoxaline), 7.88
(1H, d, J = 8.1 Hz, quinoxaline), 8.03 (1H, s, quinoxaline),
6
d, J = 7.0 Hz, CH ), 2.70 (2H, t, J = 12.4 Hz, piperidine-H),
2
3
8
.80 (2H, d, J = 12.7 Hz, piperidine-H), 6.96 (2H, d, J =
.8 Hz, 1,4-disubstituted benzene), 7.19–7.21 (3H, m,
1
3
Monosubstituted benzene), 7.27–7.32 (2H, m, Mono-
substituted benzene), 7.42–7.47 (1H, m, quinoxaline), 7.56
9.04 (1H, s, N=CH), 11.46 (1H, s, NH). C NMR
(75 MHz, DMSO-d , ppm) δ 12.44 (CH ), 47.86 (CH ),
6
3
2
(
(
8
2H, d, J = 8.9 Hz, 1,4-disubstituted benzene), 7.64–7.65
2H, m, quinoxaline), 7.88 (1H, d, J = 8.2 Hz, quinoxaline),
52.08, 52.67, 115.12, 125.11, 125.16, 126.43, 128.10,
129.21, 130.67, 136.96, 138.16, 141.61, 142.94, 150.83,
152.07. HRMS (m/z): [M+H]+ calcd for C H N :
.02 (1H, s, quinoxaline), 9.02 (1H, s, N=CH), 11.42 (1H,
21
24
6
1
3
s, NH). C NMR (75 MHz, DMSO-d , ppm) δ 31.58,
361.2135; found: 361.2122.
6
3
1
1
7.77, 42.70, 48.33, 115.36, 124.52, 125.13, 126.26,
26.43, 128.17, 128.62, 129.21, 129.49, 130.67, 136.95,
2-[2-[4-(4-(4-Methoxyphenyl)piperazin-1-yl)benzylidene]
hydrazineyl]quinoxaline (5k) Yield 65%, m.p.
260.8–263.1 °C. IR νmax (cm ): 3196 (N–H) 3062 (aro-
matic C–H), 2956 (aliphatic C–H), 1606–1510 (C=N,
38.14, 140.65, 141.63, 143.03, 150.83, 152.14. HRMS (m/
+
−1
z): [M+H] calcd for C H N : 422.2339; found:
27
27
5
4
22.2321.