JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
407
temperature and then refluxed for 6 h. On completion (as moni- N-(1,3-Benzothiazol-2-yl)-4-methyl-2-[N-(4-nitrobenzenesulfonyl)-
tored by TLC), the amide products were precipitated out from
the reaction mixture by adding 40 ml n-hexane. The carboxa-
mides (17a–l) were obtained via suction filtration, washed with
n-hexane and dried over fused silica gel or concentrated using
rotary evaporator and dried over vacuum in the case of oily
products.
1-phenylformamido] pentanamide (17d)
Yield (0.4824 g, 87.78%), mp, 197.20–198.10 ꢀC, FTIR (KBr, cmꢁ1):
3415 (NH), 3101 (C–H aromatic), 2958 (C–H aliphatic), 1692, 1654
(C¼O), 1620 (C¼N), 1607, 1568, 1437 (C¼C), 1531, 1497 (NO2),
1349, 1312 (2S¼O), 1182, 1166 (SO2N), 1092, 1003 (C–N). 1H NMR
(DMSO-d6, 400 MHz) d: 8.34 (d, J ¼ 8.72 Hz, 2H, ArH), 7.98 (d,
J ¼ 8.68 Hz, 2H, ArH), 7.90 (d, J ¼ 7.80 Hz, 1H, ArH), 7.58 (t,
J ¼ 7.76 Hz, 1H, ArH), 7.44 (t, J ¼ 7.76 Hz, 1H, ArH), 7.27 (d,
J ¼ 7.76 Hz, 1H, ArH), 7.19 (t, J ¼ 7.32 Hz, 2H, ArH), 7.15–7.07 (m,
2H, ArH), 6.94 (t, J ¼ 7.56 Hz, 1H, ArH), 6.52 (s, 1H, NH), 3.72 (t,
J ¼ 2.76 Hz, 1H, CH–C¼O), 1.41–1.34 (m, 1H, CH), 1.22–1.18 (m, 2H,
CH2), 0.82–0.76 (m, 6H, 2CH3). 13C NMR (DMSO-d6, 400 MHz) d:
173.37, 167.85 (C¼O), 153.31 (C¼N), 149.90, 147.29, 137.86, 133.37,
131.30, 129.79, 129.41, 129.08, 128.72, 128.65, 125.91, 124.82,
121.35, 118.24 (15 aromatic carbons), 54.71, 31.48, 23.13, 14.48
(four aliphatic carbons). HRMS (m/z): 552.1138 (Mþ), calculated,
552.1137.
N-(1,3-Benzothiazol-2-yl)-2-[N-(4-nitrobenzenesulfonyl)-1-
phenylformamido] acetamide (17a)
Yield (0.3888 g, 78.37%), mp, 146.20–146.80 ꢀC, FTIR (KBr, cmꢁ1):
3347 (NH), 3106 (C–H aromatic), 1727, 1698 (C¼O), 1640 (C¼N),
1606, 1585, 1469, 1444 (C¼C), 1525 (NO2), 1353, 1304 (2S¼O),
1199, 1164 (SO2N), 1092, 1072, 1013 (C–N). 1H NMR (DMSO-d6,
400 MHz) d: 8.36–8.30 (m, 3H, ArH), 8.02–7.98 (m, 3H, ArH),
7.91–7.89 (m, 1H, ArH), 7.64 (d, J ¼ 7.32 Hz, 1H, ArH), 7.45 (t,
J ¼ 7.56 Hz, 1H, ArH), 7.31 (d, J ¼ 7.80 Hz, 1H, ArH), 7.21 (t,
J ¼ 7.1 Hz, 2H, ArH), 7.02 (t, J ¼ 7.10 Hz, 2H, ArH), 3.66 (s, 2H, CH2).
13C NMR (DMSO-d6, 400 MHz) d: 170.66, 167.52 (C¼O), 149.86,
146.99, 146.17, 133.39, 129.94, 129.78, 129.09, 128.91, 128.64,
126.38, 124.89, 124.73, 122.06, 121.84, 117.49 (15 aromatic car-
bons), 48.82 (aliphatic carbon). HRMS (m/z): 497.0612 (M þ H), cal-
culated: 497.0618.
N-(1,3-Benzothiazol-2-yl)-3-methyl-2-[N-(4-nitrobenzenesulfonyl)-
1-phenylformamido] pentanamide (17e)
Yield (0.5514 g, 99.87%), mp, 158.30–158.90 ꢀC, FTIR (KBr, cmꢁ1):
3391 (NH), 3065 (C–H aromatic), 2957 (C–H aliphatic), 1693, 1640
(C¼O), 1613 (C¼N), 1602, 1583, 1469, 1455 (C¼C), 1529 (NO2),
1
N-(1,3-Benzothiazol-2-yl)-2-[N-(4-nitrobenzenesulfonyl)-1-
phenylformamido]-3-phenyl propanamide (17b)
1349, 1308 (2S¼O), 1164, 1143 (SO2N), 1092, 1067, 1020 (C–N). H
NMR (DMSO-d6, 400 MHz) d: 8.34 (d, J ¼ 8.68 Hz, 2H, ArH), 8.98 (d,
J ¼ 8.24 Hz, 2H, ArH), 7.91 (d, J ¼ 7.32 Hz, 1H, ArH), 7.59 (t,
J ¼ 7.80 Hz, 1H, ArH), 7.45 (t, J ¼ 7.76 Hz, 1H, ArH), 7.28 (d,
J ¼ 8.28 Hz, 1H, ArH), 7.20 (d, J ¼ 7.34 Hz, 2H, ArH), 7.13–7.08 (m,
2H, ArH), 6.95 (t, J ¼ 7.32 Hz,1H, ArH), 6.44 (s, 1H, NH), 3.73 (d,
J ¼ 5.15 Hz, 1H, CH–C¼O), 1.42–1.34 (m, 1H, CH), 1.22–1.18 (m, 2H,
CH2), 0.80–0.70 (m, 6H, 2CH3). 13C NMR (DMSO-d6, 400 MHz) d:
173.38, 167.86 (C¼O), 166.98 (C¼N), 153.33 (C–NO2), 149.89,
147.30, 137.86, 133.35, 131.45, 129.79, 129.41, 129.07, 128.72,
125.91, 125.83, 124.82, 121.36, 121.29, 118.22 (17 aromatic car-
bons), 54.74, 31.49, 24.49, 23.13, 14.47 (five aliphatic carbons).
HRMS (m/z): 553.1242 (M þ H), calculated, 553.1249.
Yield (0.4922 g, 83.98%), mp, 111.50–111.70 ꢀC, FTIR (KBr, cmꢁ1):
3414 (NH), 3087 (C–H aromatic), 2926 (C–H aliphatic), 1700, 1687
(C¼O), 1639 (C¼N), 1607, 1583, 1470, 1455 (C¼C), 1530, 1496
1
(NO2), 1349, 1310 (2S¼O), 1160 (SO2N), 1092, 1013 (C–N). H NMR
(DMSO-d6, 400 MHz) d: 8.14 (d, J ¼ 9.16 Hz, 2H, ArH), 7.91 (d,
J ¼ 7.32 Hz, 1H, ArH), 7.70 (d, J ¼ 8.72 Hz, 2H, ArH), 7.45 (d,
J ¼ 9.16 Hz, 2H, ArH), 7.29 (d, J ¼ 7.76 Hz, 1H, ArH), 7.21–7.15 (m,
3H, ArH), 7.12–7.07 (m, 5H, ArH), 6.95 (t, J ¼ 7.56 Hz, 1H, ArH), 3.96
(dd, J ¼ 3.64, 6.40 Hz, 1H, CH–C¼O), 2.96 (dd, J ¼ 4.56, 5.04 Hz, 1H,
CHa of CH2), 2.68 (dd, J ¼ 10.56, 10.52 Hz, 1H, CHb of CH2). 13C
NMR (DMSO-d6, 400 MHz) d: 172.72, 167.00 (C¼O), 153.30 (C¼N),
149.58, 147.16, 137.86, 137.22, 131.43, 129.79, 129.72, 129.41,
129.07, 128.71, 128.61, 128.44, 128.16, 126.87, 125.92, 125.82,
124.62, 121.33, 118.23 (19 aromatic carbons), 58.23, 38.09 (two ali-
phatic carbons). HRMS (m/z): 586.0991 (Mþ), calculated, 586.0981.
N-(1,3-Benzothiazol-2-yl)-3-methyl-2-[N-(4-nitrobenzenesulfonyl)-
1-phenylformamido] butanamide (17f)
Yield (0.5309 g, 98.66%), mp, 162.90–163.30 ꢀC, FTIR (KBr, cmꢁ1):
3398 (NH), 3110 (C–H aromatic), 2987, 2899 (C–H aliphatic), 1696,
1659 (C¼O), 1618 (C¼N), 1601, 1592, 1487 (C¼C), 1531, 1515
N-(1,3-Benzothiazol-2-yl)-3-(1H-indol-2-yl)-2-[N-(4-
nitrobenzenesulfonyl)-1-phenyl formamido]propanamide (17c)
1
(NO2), 1356, 1334 (2S¼O), 1168, 1139 (SO2N), 1094, 1071 (C–N). H
NMR (DMSO-d6, 400 MHz) d: 8.34 (d, J ¼ 7.80 Hz, 2H, ArH), 8.00 (d,
J ¼ 8.72 Hz, 1H, ArH), 7.61 (d, J ¼ 7.80 Hz, 1H, ArH), 7.29 (t,
J ¼ 8.70 Hz, 2H, ArH), 7.20 (t, J ¼ 7.56 Hz, 2H, ArH), 7.13–7.08 (m,
4H, ArH), 7.98 (t, J ¼ 7.34 Hz, 1H, ArH), 6.54 (s, 1H, NH), 3.60 (d,
J ¼ 5.96 Hz, 1H, CH-C¼O), 1.99–1.94 (m, 1H, CH), 0.81–0.76 (m, 6H,
2CH3). 13C NMR (DMSO-d6, 400 MHz) d: 172.42, 167.22 (C¼O),
160.11 (C¼N), 150.26 (C–NO2), 137.87, 133.87, 131.09, 130.83,
129.42, 129.09, 128.72, 128.45, 126.11, 125.83, 124.76, 121.56,
117.92 (15 aromatic carbons), 61.97, 31.51, 19.56, 18.24 (four ali-
phatic carbons). HRMS (m/z): 538.0980 (Mþ), calculated, 538.0981.
Yield (0.6209 g, 99.33%), mp, 140.00–140.40 ꢀC, FTIR (KBr, cmꢁ1):
3413, 3362 (2NH), 3004 (C–H aromatic), 2984 (C–H aliphatic), 1693,
1640 (C¼O), 1619 (C¼N), 1601, 1458, 1403 (C¼C), 1528 (NO2),
1349, 1312 (2S¼O), 1163 (SO2N), 1091, 1012 (C–N). 1H NMR
(DMSO-d6, 400 MHz) d: 10.80 (NH of indole), 8.66 (s, 1H, NH of
amide), 7.93 (d, J ¼ 7.36 Hz, 1H, ArH), 7.83 (d, J ¼ 8.68 Hz, 2H, ArH),
7.58 (d, J ¼ 7.80 Hz, 1H, ArH), 7.46 (t, J ¼ 8.24 Hz, 2H, ArH), 7.19 (t,
J ¼ 7.54 Hz, 4H, ArH), 7.12–7.04 (m, 5H, ArH), 6.97–6.80 (m, 3H,
ArH), 3.94 (dd, J ¼ 4.60, 2.76 Hz, 1H, CH–C¼O), 3.08 (dd, J ¼ 4.12,
3.68 Hz, 1H, CHa of CH2), 2.83 (dd, J ¼ 10.52, 10.08 Hz, 1H, CHb of
CH2). 13C NMR (DMSO-d6, 400 MHz) d: 173.44, 167.09 (C¼O),
153.38 (C¼N), 148.83, 146.49, 137.85, 137.55, 136.50, 129.40,
129.03, 128.70, 128.17, 127.34, 126.99, 125.81, 125.48, 124.96,
123.71, 121.32, 121.27, 121.12, 118.71, 118.24, 111.72, 109.21 (23
N-(1,3-Benzothiazol-2-yl)-4-hydroxy-1-(4-
nitrobenzenesulfonyl)pyrrolidine-2-carboxamide (17g)
aromatic carbons), 57.16, 28.19 (two aliphatic carbons). HRMS (m/z): Yield (0.4479 g, 99.96%), mp, 127.40–127.90 ꢀC, FTIR (KBr, cmꢁ1):
625.1110 (Mþ), calculated, 625.1109.
3492 (NH), 3389 (OH), 3118 (C–H aromatic), 2987, 2899 (C–H