Y. Ono, et al.
BioorganicChemistry104(2020)104245
2-[(4″’-Hydroxyphenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-phenylqui-
1403, 1256, 1228, 1183, 1078, 1019, 994, 942, 838, 758, 742, 699,
noxaline (5b): 51% yield. IR (ATR): νmax 3141, 2928, 2171, 2159, 2040,
598, 524 cm−1
;
1H NMR (400 MHz, DMSO‑d6): δ 7.97 (2H, d,
1614, 1598, 1567, 1494, 1476, 1286, 1239, 1179, 1081, 981, 839, 767,
J = 9.2 Hz, H-2″ and H-6″), 7.87 [1H, d, J = 7.8 Hz, (H-5 or H-8)],
7.69 [1H, td, J = 6.0 Hz and 1.6 Hz, (H-6 or H-7)], 7.60–7.53 [2H, m,
(H-5 or H-8) and (H-6 or H-7)], 7.26 (2H, t, J = 8.0 Hz, H-9′ and H-11′),
7.14 (2H, d, J = 8.7 Hz, H-3″ and H-5″), 7.03 (2H, d, J = 7.8 Hz, H-8′
and H-12′), 6.83 (1H, t, J = 7.3 Hz, H-10′), 3.85 (3H, s, OMe), 3.53
(4H, t, J = 4.8 Hz, H-3′ and H-5′), 3.39 (4H, t, J = 4.8 Hz, H-2′ and H-
6′); 13C NMR (100 MHz, DMSO‑d6): δ 168.1, 163.1, 157.4, 153.4, 151.3,
148.9, 139.6, 139.2, 130.6, 129.6 (2C), 129.2 (2C), 128.8, 128.0,
127.8, 119.8, 116.2 (2C), 115.7, 115.6 (2C), 56.1, 49.9 (2C), 48.6 (2C);
HRESITOFMS: m/z 497.1759 [M + H]+ (calcd. for C27H25N6O2S,
497.1760).
762, 691, 639, 517 cm−1
;
1H NMR (400 MHz, DMSO‑d6): δ 8.11 [1H,
dd, J = 8.0 Hz and 1.1 Hz, (H-5 or H-8)], 7.87–7.81 [5H, m, H-2′, H-2″,
H-6′, H-6″, and (H-6 or H-7)], 7.78 [1H, td, J = 6.8 Hz and 1.2 Hz, (H-6
or H-7)], 7.71 [1H, dd, J = 8.2 Hz and 1.4 Hz, (H-5 or H-8)], 7.64–7.63
(3H, m, H-3′, H-4′, and H-5′), 6.96 (2H, d, J = 8.7 Hz, H-3″ and H-5″);
13C NMR (100 MHz, DMSO‑d6): δ 168.3, 161.9, 157.0, 152.7, 151.7,
141.1, 140.4, 136.6, 131.7, 131.0, 130.9, 129.52, 129.47 (2C), 129.38
(4C), 128.3, 116.9 (2C), 114.1; HRESITOFMS: m/z 399.0916 [M + H]+
(calcd. for C22H15N4O2S, 399.0916).
2-[(4″’-Aminophenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-phenylquinoxa-
line (5c): 44% yield. IR (ATR): νmax 3428, 3321, 2035, 1631, 1610,
2-[(4″’-Hydroxyphenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-phenylpiper-
azilquinoxaline (5h): 81% yield. IR (ATR): νmax 3205, 2920, 2849, 1609,
1595, 1493, 1481, 1232, 1169, 1139, 1020, 943, 765, 754, 688, 632,
600, 517 cm−1; 1H NMR (400 MHz, DMSO‑d6): δ 7.88–7.85 [3H, m, H-
2″, H-6″, and (H-5 or H-8)], 7.69 [1H, td, J = 6.4 Hz and 2.0 Hz, (H-6
or H-7)], 7.60–7.53 [2H, m, (H-5 or H-8) and (H-6 or H-7)], 7.26 (2H, t,
J = 7.2 Hz, H-9′ and H-11′), 7.03 (2H, d, J = 7.8 Hz, H-8′ and H-12′),
6.95 (2H, d, J = 8.7 Hz, H-3″ and H-5″), 6.83 (1H, t, J = 7.3 Hz, H-
10′), 3.54–3.35 (8H, m, H-2′, H-3′, H-5′, and H-6′); 13C NMR (100 MHz,
DMSO‑d6): δ 168.4, 162.0, 157.0, 153.4, 151.3, 149.0, 139.6, 139.2,
130.6, 129.6 (2C), 129.4, 128.8, 128.0, 127.8, 119.8, 116.9, 116.2
(2C), 114.1, 49.9 (2C), 48.6 (2C); HRESITOFMS: m/z 505.1406
[M + Na]+ (calcd. for C26H22N6O2SNa, 505.1423).
1496, 1329, 1173, 1080, 980, 829, 759, 692, 597, 582, 513 cm−1
;
1H
NMR (400 MHz, DMSO‑d6): δ 8.11 [1H, dd, J = 8.2 Hz and 1.4 Hz, (H-5
or H-8)], 7.86–7.81 [3H, m, H-2′, H-6′, and (H-6 or H-7)], 7.78 [1H, td,
J = 7.6 Hz and 1.4 Hz, (H-6 or H-7)], 7.71 [1H, dd, J = 7.8 Hz and
1.4 Hz, (H-5 or H-8)], 7.67 (2H, d, J = 8.7 Hz, H-2″ and H-6″), 7.64
(3H, t, J = 3.2 Hz, H-3′, H-4′, and H-5′), 6.68 (2H, d, J = 8.7 Hz, H-3″
and H-5″), 6.06 (2H, s, NH2); 13C NMR (100 MHz, DMSO‑d6): δ 169.0,
155.8, 153.5, 152.6, 151.9, 141.1, 140.4, 136.6, 131.7, 131.0, 130.9,
129.52, 129.47 (2C), 129.37 (2C), 128.9 (2C), 128.2, 114.1 (2C), 109.6;
HRESITOFMS: m/z 398.1065 [M + H]+ (calcd. for C22H16N5OS,
398.1076).
2-[(4″’-Methoxyphenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-methylpiper-
azilquinoxaline (5d): 79% yield. IR (ATR): νmax 1613, 1586, 1537, 1495,
1468, 1422, 1469, 1454, 1024, 1003, 835, 732, 706, 622, 597,
519 cm−1; 1H NMR (400 MHz, CDCl3): δ 8.03 (2H, d, J = 8.7 Hz, H-2″
and H-6″), 7.84 [1H, dd, J = 8.2 Hz and 0.9 Hz, (H-5 or H-8)], 7.62
[1H, dd, J = 8.2 Hz and 1.4 Hz, (H-5 or H-8)], 7.57 [1H, td, J = 7.6 Hz
and 1.6 Hz, (H-6 or H-7)], 7.45 [1H, td, J = 7.2 Hz and 1.2 Hz, (H-6 or
H-7)], 7.01 (2H, d, J = 8.7 Hz, H-3″ and H-5″), 3.87 (3H, s, OMe), 3.50
(4H, t, J = 4.6 Hz, H-2′ and H-6′), 2.68 (4H, t, J = 4.6 Hz, H-3′ and H-
5′), 2.41 (3H, s, Me); 13C NMR (100 MHz, CDCl3): δ 168.4, 162.8,
157.5, 153.2, 148.4, 139.8, 139.6, 129.6, 129.0 (2C), 128.1, 127.8,
127.6 (2C), 116.2, 114.7, 55.6, 54.8 (2C), 49.7 (2C), 46.2; HRESITO-
FMS: m/z 435.1602 [M + H]+ (calcd. for C22H23N6O2S, 435.1603).
2-[(4″’-Hydroxyphenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-methlypiper-
azilquinoxaline (5e): 41% yield. IR (ATR): νmax 3650, 3629, 2844, 2366,
2357, 1611, 1560, 1452, 1405, 1366, 1346, 1269, 1161, 1139, 1077,
2-[(4″’-Aminophenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-phenylpier-
azilquinoxaline (5i): 77% yield. IR (ATR): νmax 3359, 3164, 3070, 2158,
2133, 1606, 1493, 1405, 1236, 1137, 1079, 1020, 907, 870, 834, 756,
575, 518, 501, 490 cm−1; 1H NMR (400 MHz, DMSO‑d6): δ 7.86 [1H, d,
J = 8.2 Hz, (H-5 or H-8)], 7.71–7.66 [3H, m, H-2″, H-6″, and (H-6 or H-
7)], 7.59–7.53 [2H, m, (H-5 or H-8) and (H-6 or H-7)], 7.25 (2H, t,
J = 7.2 Hz, H-9′ and H-11′), 7.02 (2H, d, J = 7.8 Hz, H-8′ and H-12′),
6.83 (1H, t, J = 7.3 Hz, H-10′), 6.68 (2H, d, J = 8.7 Hz, H-3″ and H-
5″), 6.05 (2H, s, NH2), 3.51–3.53 (4H, m, H-3′ and H-5′), 3.40–3.36
(4H, m, H-2′ and H-6′); 13C NMR (100 MHz, DMSO‑d6): δ 169.1, 155.9,
153.4, 153.4, 151.1, 149.1, 139.5, 139.2, 130.5, 129.6 (2C), 128.9
(2C), 128.8, 127.9, 127.8, 119.9, 116.2 (2C), 114.2 (2C), 109.6, 49.9
(2C), 48.6 (2C); HRESITOFMS: m/z 504.1585 [M + Na]+ (calcd. for
C
26H23N7OSNa, 504.1583).
3-N-Benzylpiperazil-2-[(4″’-methoxyphenyl)-1″,3″,4″-oxadiazol-2″-
1002, 941, 840, 746, 736, 713, 597, 526, 487 cm−1
;
1H NMR
thio]quinoxaline (5j): 97% yield. IR (ATR): νmax 1612, 1537, 1494,
(500 MHz, Acetone‑d6): δ 8.02 (1H, s, OH), 7.95 (2H, d, J = 8.6 Hz, H-
2″ and H-6″), 7.85 [1H, d, J = 8.0 Hz, (H-5 or H-8)], 7.67 [1H, td,
J = 5.4 Hz and 1.6 Hz, (H-6 or H-7)], 7.59–7.53 [2H, m, (H-5 or H-8)
and (H-6 or H-7)], 7.05 (2H, d, J = 8.6 Hz, H-3″ and H-5″), 3.47 (4H, s,
H-2′ and H-6′), 2.65 (4H, t, J = 4.0 Hz, H-3′ and H-5′), 2.34 (3H, s, Me);
13C NMR (125 MHz, Acetone‑d6): δ 168.4, 161.2, 156.9, 153.4, 149.0,
139.8, 139.3, 129.7, 129.0 (2C), 128.0, 127.7, 127.6, 116.3 (2C),
115.2, 54.6 (2C), 49.7 (2C), 45.5; HRESITOFMS: m/z 421.1417
[M + H]+ (calcd. for C21H21N6O2S, 421.1447).
1423, 1308, 1256, 1173, 1162, 1074, 1024, 999, 842, 763, 735, 696,
597, 523 cm−1
;
1H NMR (400 MHz, DMSO‑d6): δ 7.97 (2H, d,
J = 8.7 Hz, H-2″ and H-6″), 7.84 [1H, d, J = 8.2 Hz, (H-5 or H-8)],
7.67 [1H, td, J = 5.6 Hz and 2.4 Hz, (H-6 or H-7)], 7.57–7.51 [2H, m,
(H-5 or H-8) and (H-6 or H-7)], 7.36–7.33 (4H, m, H-9′, H-10′, H-12′,
and H-13′), 7.28 (1H, td, J = 8.5 Hz and 4.1 Hz, H-11′), 7.15 (2H, d,
J = 9.2 Hz, H-3″ and H-5″), 3.85 (3H, s, OMe), 3.59 (2H, s, H-7′), 3.39
(4H, s, H-2′ and H-6′), 2.63 (4H, s, H-3′ and H-5′); 13C NMR (100 MHz,
DMSO‑d6): δ 168.1, 163.1, 157.4, 153.4, 148.9, 139.6, 139.1, 138.3,
130.5, 129.5 (2C), 129.2 (2C), 128.8 (2C), 128.7, 127.9, 127.8, 127.6,
115.7, 115.6 (2C), 62.5, 56.1, 52.7 (2C), 50.0 (2C); HRESITOFMS: m/z
511.1901 [M + H]+ (calcd. for C28H27N6O2S, 511.1916).
2-[(4″’-Aminophenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-methylpier-
azilquinoxaline (5f): 77% yield. IR (ATR): νmax 3445, 3334, 3219, 1639,
1606, 1577, 1495, 1476, 1444, 1268, 1170, 1141, 1028, 1005, 759,
745, 598, 528, 514 cm−1; 1H NMR (400 MHz, Acetone‑d6): δ 7.85 [1H,
d, J = 8.2 Hz, (H-5 or H-8)], 7.77 (2H, d, J = 8.7 Hz, H-2″ and H-6″),
7.66 [1H, td, J = 6.4 Hz and 2.0 Hz, (H-6 or H-7)], 7.59–7.51 [2H, m,
(H-5 or H-8) and (H-6 or H-7)], 6.81 (2H, d, J = 8.7 Hz, H-3″ and H-5″),
5.51 (2H, s, NH2), 3.46 (4H, t, J = 4.6 Hz, H-2′ and H-6′), 2.64 (4H, t,
J = 4.8 Hz, H-3′ and H-5′), 2.33 (3H, s, Me); 13C NMR (100 MHz,
Acetone‑d6): δ 169.0, 155.8, 153.4, 152.6, 149.1, 139.7, 139.3, 129.6,
128.5 (2C), 127.9, 127.7, 127.6, 114.0 (2C), 111.2, 54.6 (2C), 49.7
(2C), 45.5; HRESITOFMS: m/z 442.1432 [M + Na]+ (calcd. for
3-N-Benzylpiperazil-2-[(4″’-hydroxyphenyl)-1″,3″,4″-oxadiazol-2″-
thio]quinoxaline (5k): 87% yield. IR (ATR): νmax 3175, 2570, 2359,
2047, 1609, 1555, 1490, 1288, 1170, 1124, 1074, 1003, 860, 840,
7638, 699, 682, 631, 540, 469 cm−1; 1H NMR (400 MHz, DMSO‑d6): δ
10.62–10.29 (1H, br, OH), 7.87–7.83 [3H, m, H-2″, H-6″, and (H-5 or
H-8)], 7.67 [1H, t, J = 6.0 Hz and 2.8 Hz, (H-6 or H-7)], 7.57–7.51 [2H,
m, (H-5 or H-8) and (H-6 or H-7)], 7.38–7.32 (4H, m, H-9′, H-10′, H-
12′, and H-13′), 7.28 (1H, td, J = 8.6 Hz and 4.4 Hz, H-11′), 6.96 (2H,
d, J = 8.7 Hz, H-3″ and H-5″), 3.58 (2H, s, H-2′ and H-6′), 2.62 (4H, t,
J = 4.4 Hz, H-3′ and H-5′), 2.08 (1H, s, H-7′); 13C NMR (100 MHz,
DMSO‑d6): δ 168.4, 161.9, 157.0, 153.4, 149.0, 139.6, 139.1, 138.4,
130.5, 129.5 (2C), 129.4 (2C), 128.8 (2C), 128.7, 127.9, 127.8, 127.6,
C
21H21N7OSNa, 442.1426).
2-[(4″’-Methoxyphenyl)-1″,3″,4″-oxadiazol-2″-thio]-3-N-phenylpiper-
azilquinoxaline (5g): 71% yield. IR (ATR): νmax 1611, 1597, 1494, 1476,
8