Paper
Organic & Biomolecular Chemistry
1.3 Hz, 2H), 7.62–7.56 (m, 2H), 7.49 (td, J = 8.0, 1.2 Hz, 1H), 1-(4-Fluorophenyl)-2-(2-phenylbenzo[d]imidazo[2,1-b]thiazol-3-
7.41 (t, J = 7.9 Hz, 2H), 7.18 (d, J = 8.4 Hz, 2H), 7.03 (d, J = 8.4 yl)ethane-1,2-dione (3m)
Hz, 2H); 13C NMR (125 MHz, CDCl3) δ 191.5, 183.0, 158.9,
155.3, 135.7, 134.3, 133.9, 133.0, 131.5, 131.0, 129.8, 129.4,
128.5, 128.0, 126.8, 126.0, 125.2, 123.7, 118.7; HRMS (ESI)
(m/z) calcd for C23H14ClN2O2S [M + H]+ 417.0459; found 417.0462.
1
Yellow solid; yield 81%; m. p. 201–203 °C; H NMR (500 MHz,
CDCl3) δ 9.17 (d, J = 7.2 Hz, 1H), 7.78–7.74 (m, 3H), 7.56 (s,
1H), 7.47 (s, 1H), 7.27–7.24 (m, 3H), 7.10–7.05 (m, 4H); 13C
NMR (125 MHz, CDCl3) δ 189.7, 182.8, 166.1(JC–F = 257 Hz),
160.4, 155.3, 133.8, 13 2.6, 132.1 (JC–F = 9 Hz), 130.1, 129.8
(JC–F = 15 Hz), 129.5, 127.8, 126.7, 125.9, 125., 123.6, 118.5,
115.6 (JC–F = 21 Hz); HRMS (ESI) (m/z) calcd for C23H14FN2O2S
[M + H]+ 401.0755; found 401.0760.
1-(2-(2-Bromophenyl)benzo[d]imidazo[2,1-b]thiazol-3-yl)-2-
phenylethane-1,2-dione (3h)
1
Yellow solid; yield 53%; m. p. 199–201 °C; H NMR (500 MHz,
CDCl3) δ 9.23 (d, J = 8.3 Hz, 1H), 7.81 (d, J = 7.7 Hz, 1H),
7.62–7.58 (m, 3H), 7.55–7.48 (m, 2H), 7.33 (t, J = 7.7 Hz, 2H),
7.24–7.18 (m, 2H), 7.07–7.02 (m, 2H); 13C NMR (125 MHz,
CDCl3) δ 191.7, 182.9, 158.2, 155.1, 134.3, 133.8, 133.2, 133.0,
132.2, 132.1, 130.8, 130.0, 129.3, 128.3, 126.8, 126.2, 126.1,
125.9, 124.7, 123.7, 118.8; 13C NMR (125 MHz, CDCl3) δ 191.7,
182.9, 158.2, 155.1, 134.3, 133.8, 133.2, 133.0, 132.2, 132.1,
130.8, 130.0, 129.3, 128.3, 126.8, 126.2, 126.1, 125.9, 124.7,
123.7, 118.8; HRMS (ESI) (m/z) calcd for C23H13BrN2O2S
[M + H]+ 459.9881; found 460.9976.
1-(3-Chlorophenyl)-2-(2-phenylbenzo[d]imidazo[2,1-b]thiazol-3-
yl)ethane-1,2-dione (3n)
Light yellow solid; yield 76%; m. p. 183–185 °C; 1H NMR
(500 MHz, CDCl3) δ 9.19 (d, J = 8.5 Hz, 1H), 7.80 (d, J = 8.0 Hz,
1H), 7.61–7.56 (m, 3H), 7.53–7.47 (m, 2H), 7.32 (t, J = 7.7 Hz,
1H), 7.30–7.22 (m, 4H), 7.10 (t, J = 7.6 Hz, 2H); 13C NMR
(100 MHz, CDCl3) δ 190.1, 182.4, 160.7, 155.5, 134.8, 134.7,
133.9, 132.5, 130.2, 129.8, 129.7, 129.6, 129.0, 127.9, 127.5,
126.8, 126.0, 124.9, 123.7, 118.6; HRMS (ESI) (m/z) calcd for
C23H14ClN2O2S [M + H]+ 417.0459; found 417.0461.
1-(2-(Benzo[d][1,3]dioxol-5-yl)benzo[d]imidazo[2,1-b]thiazol-3-
yl)-2-phenylethane-1,2-dione (3i)
1-(4-Methoxyphenyl)-2-(2-(4-methoxyphenyl)benzo[d]imidazo
[2,1-b]thiazol-3-yl)ethane-1,2-dione (3o)
Light yellow solid; yield 81%; m. p. 197–199 °C; 1H NMR
(500 MHz, CDCl3) δ 9.19 (d, J = 8.3 Hz, 1H), 7.79–7.76 (m, 3H),
7.61–7.54 (m, 2H), 7.50–7.41 (m, 3H), 6.79 (s, 1H), 6.69 (dd, J =
7.9, 1.5 Hz, 1H), 6.39 (d, J = 7.9 Hz, 1H), 5.88 (s, 2H); 13C NMR
(100 MHz, CDCl3) δ 191.2, 182.9, 159.5, 155.0, 148.3, 146.7,
134.4, 133.3, 132.5, 129.4, 129.1, 126.0, 124.9, 124.9, 124.5,
117.6, 109.7, 107.2, 101.2; HRMS (ESI) (m/z) calcd for
C24H15N2O4S [M + H]+ 427.0747; found 427.0764.
1
Yellow solid; yield 81%; m. p. 187–189 °C; H NMR (500 MHz,
CDCl3) δ 9.19 (d, J = 8.4 Hz, 1H), 7.77 (d, J = 7.8 Hz, 1H), 7.71
(d, J = 8.8 Hz, 2H), 7.55 (t, J = 7.47 Hz, 1H), 7.46 (t, J = 7.3 Hz,
1H), 7.26 (d, J = 8.68 Hz, 2H), 6.86 (d, J = 9.0 Hz, 2H), 6.56 (d,
J = 8.7 Hz, 2H), 3.88 (s, 3H), 3.74 (s, 3H); 13C NMR (100 MHz,
CDCl3) δ 190.2, 183.6, 164.2, 160.5, 160.2, 155.0, 134.0, 131.8,
131.5, 129.7, 126.6, 126.5, 125.7, 125.2, 125.1, 123.6, 118.6,
113.7, 113.2, 55.5, 55.2; HRMS (ESI) (m/z) calcd for
C25H19N2O4S [M + H]+ 443.1060; found 443.1067.
1-(4-Methoxyphenyl)-2-(2-phenylbenzo[d]imidazo[2,1-b]thiazol-
3-yl)ethane-1,2-dione (3k)
Light yellow solid; yield 79%; m. p. 151–153 °C; 1H NMR
(500 MHz, CDCl3) δ 9.18 (d, J = 8.5 Hz, 1H), 7.74 (d, J = 7.9 Hz,
1H), 7.70 (d, J = 8.8 Hz, 2H), 7.54 (t, J = 7.7 Hz, 1H), 7.45 (t, J =
7.6 Hz, 1H), 7.30 (d, J = 7.2 Hz, 2H), 7.23 (t, J = 7.4 Hz, 1H),
1-(3,4-Dimethoxyphenyl)-2-(2-(4-methoxyphenyl)benzo[d]
imidazo[2,1-b]thiazol-3-yl)ethane-1,2-dione (3p)
1
Yellow solid; yield 79%; m. p. 143–145 °C; H NMR (400 MHz,
CDCl3) δ 9.20 (d, J = 8.4 Hz, 1H), 7.77 (d, J = 7.9 Hz, 1H), 7.55
(t, J = 7.9 Hz, 1H), 7.47–7.42 (m, 2H), 7.18 (d, J = 8.5 Hz, 2H),
7.10 (s, 1H), 6.81 (d, J = 8.4 Hz, 1H), 6.61 (d, J = 8.5 Hz, 2H),
3.95 (s, 3H), 3.83 (s, 3H), 3.72 (s, 3H); 13C NMR (125 MHz,
CDCl3) δ 190.6, 183.4, 160.4, 160.3, 154.1, 149.0, 134.0, 131.6,
129.7, 126.8, 126.7, 125.7, 125.3, 125.2, 123.6, 118.7, 113.1,
110.1, 109.8, 56.1, 55.8, 55.1; HRMS (ESI) (m/z) calcd for
C26H21N2O5S [M + H]+ 473.1166; found 473.1171.
7.10 (t, J = 7.6 Hz, 2H), 6.86 (d, J = 8.8 Hz, 2H), 3.87 (s, 3H); 13
C
NMR (125 MHz, CDCl3) δ 189.9, 183.5, 164.2, 160.1, 154.9,
133.9, 132.7, 131.8, 130.0, 129.8, 129.3, 127.6, 126.6, 126.4,
125.7, 125.1, 123.5, 118.6, 113.7, 55.4; HRMS (ESI) (m/z) calcd
for C24H17N2O3S [M + H]+ 413.0954; found 413.0960.
1-(3,4-Dimethoxyphenyl)-2-(2-phenylbenzo[d]imidazo[2,1-b]
thiazol-3-yl)ethane-1,2-dione (3l)
1-(4-Fluorophenyl)-2-(2-(4-methoxyphenyl)benzo[d]imidazo
[2,1-b]thiazol-3-yl)ethane-1,2-dione (3q)
Light yellow solid; yield 76%; m. p. 173–175 °C; 1H NMR
(500 MHz, CDCl3) δ 9.20 (d, J = 8.3 Hz, 1H), 7.78 (dd, J = 8.0,
0.8 Hz, 1H), 7.56 (td, J = 7.3, 1.2 Hz, 1H), 7.48–7.44 (m, 2H), Light brown solid; yield 85%; m. p. 173–175 °C; 1H NMR
7.29 (dd, J = 6.8, 1.2 Hz, 2H), 7.23 (t, J = 7.4 Hz, 1H), 7.11–7.08 (400 MHz, CDCl3) δ 9.17 (d, J = 8.0 Hz, 1H), 7.78–7.73 (m, 3H),
(m, 3H), 6.83 (d, J = 8.5 Hz, 1H), 3.96 (s, 3H), 3.83 (s, 3H); 13C 7.56 (td, J = 7.4, 1.2 Hz, 1H), 7.46 (td, J = 7.0, 1.1 Hz, 1H), 7.20
NMR (100 MHz, CDCl3) δ 190.2, 183.3, 160.1, 154.9, 148.9, (d, J = 7.6, 2H), 7.06 (t, J = 8.5, 2H), 6.61 (d, J = 8.6, 2H), 3.73 (s,
133.9, 132.8, 130.0, 129.8, 129.1, 127.7, 126.6, 125.8, 125.4, 3H); 13C NMR (100 MHz, CDCl3) δ 189.9, 182.8, 166.1 (JC–F
=
125.2, 123.5, 118.6, 110.2, 109.8, 56.0, 55.8; HRMS (ESI) (m/z) 257 Hz), 160.6, 160.5, 155.4, 133.9, 132.1 (JC–F = 10 Hz), 131.6,
calcd for C25H19N2O4S [M + H]+ 443.1060; found 443.1068.
129.7, 126.7, 125.8, 125.0, 124.9, 123.6, 118.5, 115.7 (JC–F = 22 Hz),
Org. Biomol. Chem.
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