R. Akunuri et al.
Bioorganic Chemistry 116 (2021) 105288
MHz, DMSO‑d6): δ 152.9, 149.6, 144.0, 138.6, 131.6, 131.0, 130.6,
128.1, 121.1, 117.0, 116.9, 111.3, 74.6, 12.9; HRMS (ESI): m/z calcu-
lated for [M+2]+ C16H15BrN3O 346.0398; found 346.0386.
1H), 7.53 (d, J = 7.9 Hz, 1H), 7.51–7.46 (m, 2H), 7.46–7.42 (m, 2H),
7.40 (dd, J = 8.2, 0.8 Hz, 1H), 7.13 (ddd, J = 8.2, 7.0, 1.1 Hz, 1H), 6.98
(ddd, J = 8.0, 7.1, 1.0 Hz, 1H), 6.83 (dd, J = 2.2, 0.7 Hz, 1H), 5.24 (s,
2H), 2.25 (s, 3H); 13C NMR (125 MHz, DMSO‑d6): δ 149.5, 137.7, 137.5,
133.9, 132.8, 130.2, 128.8, 127.8, 123.4, 121.0, 119.7, 112.2, 104.1,
75.0, 12.7; HRMS (ESI): m/z calculated for [M+H]+ C17H16ClN2O
343.0446; found 343.0490.
4.4.17. (E)-1-(1H-pyrrolo[2,3-b]pyridin-3-yl)ethan-1-one O-(4-
chlorobenzyl) oxime (5q)
Off-white solid; yield 75%; 1H NMR (500 MHz, DMSO‑d6): δ 11.95 (s,
1H), 8.34 (dd, J = 7.9, 1.5 Hz, 1H), 8.25 (dd, J = 4.7, 1.6 Hz, 1H), 7.92
(d, J = 2.3 Hz, 1H), 7.48 (d, J = 8.5 Hz, 2H), 7.44 (d, J = 8.5 Hz, 2H),
7.12 (dd, J = 7.9, 4.7 Hz, 1H), 5.20 (s, 2H), 2.25 (s, 3H); 13C NMR (125
MHz, DMSO‑d6): δ 152.9, 149.6, 144.0, 138.1, 132.6, 131.0, 130.2,
128.7, 128.1, 117.0, 116.9, 111.3, 74.5, 12.9; HRMS (ESI): m/z calcu-
lated for [M+H]+ C16H15ClN3O 300.0904; found 300.0949.
4.4.24. (Z)-1H-indole-3-carbaldehyde O-(4-chlorobenzyl) oxime (Z-9a)
1
Off-white solid; yield 23%; H NMR (500 MHz, CDCl3): δ 8.35 (s,
1H), 8.28 (s, 1H), 8.14 (d, J = 7.8 Hz, 1H), 7.49 (d, J = 8.4 Hz, 2H), 7.37
(d, J = 8.0 Hz, 1H), 7.36–7.32 (m, 3H), 7.29–7.26 (m, 1H), 7.25–7.20
(m, 1H), 5.17 (s, 2H); 13C NMR (125 MHz, CDCl3): δ 144.9, 137.2, 136.6,
131.5, 130.0, 127.0, 124.5, 123.5, 122.3, 121.7, 121.3, 111.1, 110.5,
75.2; HRMS (ESI): m/z calculated for [M+H]+ C16H14ClN2O 285.0795;
found 285.0811.
4.4.18. (E)-1-(1-methyl-1H-indol-3-yl)ethan-1-one O-(4-chlorobenzyl)
oxime (5r)
Off-white solid; yield 82%; 1H NMR (500 MHz, DMSO‑d6): δ 8.08 (d,
J = 7.9 Hz, 1H), 7.78 (s, 1H), 7.48 (d, J = 8.5 Hz, 2H), 7.46–7.42 (m,
3H), 7.21 (t, J = 8.2 Hz, 1H), 7.10 (t, J = 8.0 Hz, 1H), 5.19 (s, 2H), 3.80
(s, 3H), 2.24 (s, 3H); 13C NMR (125 MHz, DMSO‑d6): δ 152.8, 138.2,
137.9, 132.5, 131.9, 130.2, 128.7, 125.0, 123.2, 122.6, 120.7, 111.6,
110.3, 74.5, 33.1, 13.4; HRMS (ESI): m/z calculated for [M+H]+
C18H18ClN2O 313.1108; found 313.1115.
4.4.25. (E)-1H-indole-3-carbaldehyde O-(4-chlorobenzyl) oxime (E-9a)
1
Off-white solid; yield 61%; H NMR (500 MHz, CDCl3): δ 8.48 (s,
1H), 8.19 (d, J = 2.8 Hz, 1H), 7.77 (d, J = 4.9 Hz, 2H), 7.49 (d, J = 8.4
Hz, 2H), 7.42 (d, J = 7.6 Hz, 1H), 7.31 (d, J = 8.4 Hz, 2H), 7.28 (dd, J =
7.1, 1.1 Hz, 1H), 7.25–7.21 (m, 1H), 5.26 (s, 2H); 13C NMR (125 MHz,
CDCl3): δ 139.5, 137.2, 134.8, 131.6, 130.4, 129.6, 126.4, 123.0, 121.7,
121.1, 118.2, 111.4, 107.2, 75.7; HRMS (ESI): m/z calculated for
[M+H]+ C16H14ClN2O 285.0795; found 285.0816.
4.4.19. (E)-1-(1-methyl-1H-indol-3-yl)ethan-1-one O-(4-bromobenzyl)
oxime (5s)
Off-white solid; yield 80%; 1H NMR (500 MHz, DMSO‑d6): δ 8.07 (d,
J = 7.9 Hz, 1H), 7.79 (s, 1H), 7.57 (d, J = 8.3 Hz, 2H), 7.45 (d, J = 8.2
Hz, 1H), 7.42 (d, J = 8.3 Hz, 2H), 7.21 (t, J = 7.6 Hz, 1H), 7.10 (t, J =
7.5 Hz, 1H), 5.17 (s, 2H), 3.80 (s, 3H), 2.24 (s, 3H); 13C NMR (125 MHz,
DMSO‑d6): δ 152.8, 138.7, 137.9, 131.9, 131.6, 130.5, 124.9, 123.1,
122.6, 121.1, 120.7, 111.5, 110.3, 74.5, 33.1, 13.4; HRMS (ESI): m/z
calculated for [M+H]+ C18H18BrN2O 357.0603; found 357.0564.
4.4.26. (Z)-1H-indole-3-carbaldehyde O-(4-bromobenzyl) oxime (Z-9b)
1
Off-white solid; yield 20%; H NMR (500 MHz, CDCl3): δ 8.35 (s,
1H), 8.27 (s, 1H), 8.14 (d, J = 7.8 Hz, 1H), 7.40 (d, J = 8.4 Hz, 2H), 7.37
(d, J = 8.0 Hz, 1H), 7.35 (d, J = 2.7 Hz, 1H), 7.33 (d, J = 8.4 Hz, 2H),
7.28 (dd, J = 7.1, 1.2 Hz, 1H), 7.24–7.20 (m, 1H), 5.18 (s, 2H); 13C NMR
(125 MHz, CDCl3): δ 144.9, 136.7, 136.6, 133.5, 129.7, 128.5, 127.0,
124.5, 123.5, 122.3, 121.3, 111.1, 110.5, 75.2; HRMS (ESI): m/z
calculated for [M+H]+ C16H14BrN2O 329.0290; found 329.0301.
4.4.20. (E)-1-(1-benzyl-1H-indol-3-yl)ethan-1-one O-(4-bromobenzyl)
oxime (5t)
4.4.27. (E)-1H-indole-3-carbaldehyde O-(4-bromobenzyl) oxime (E-9b)
Off-white solid; yield 60%; 1H NMR (500 MHz, CDCl3): δ 8.42 (d, J =
47.1 Hz, 1H), 8.18 (d, J = 2.8 Hz, 1H), 7.77 (d, J = 5.0 Hz, 2H), 7.41 (d,
J = 7.6 Hz, 1H), 7.37 (d, J = 8.5 Hz, 2H), 7.35–7.31 (m, 2H), 7.29–7.25
(m, 1H), 7.25–7.20 (m, 1H), 5.28 (s, 2H); 13C NMR (125 MHz, CDCl3): δ
139.5, 136.7, 134.8, 133.6, 130.4, 129.2, 128.6, 126.4, 123.0, 121.1,
118.2, 111.4, 107.3, 75.6; HRMS (ESI): m/z calculated for [M+H]+
C16H14BrN2O 329.0290; found 329.0293.
Off-white solid; yield 89%; 1H NMR (500 MHz, DMSO‑d6): δ 8.08 (d,
J = 7.8 Hz, 1H), 8.00 (s, 1H), 7.58 (d, J = 8.3 Hz, 2H), 7.45 (d, J = 8.2
Hz, 1H), 7.42 (d, J = 8.3 Hz, 2H), 7.33–7.28 (m, 2H), 7.28–7.20 (m, 3H),
7.15 (t, J = 7.1 Hz, 1H), 7.08 (t, J = 7.2 Hz, 1H), 5.44 (s, 2H), 5.18 (s,
2H), 2.26 (s, 3H); 13C NMR (125 MHz, DMSO‑d6): δ 152.8, 138.7, 138.2,
137.2, 131.6, 131.4, 130.5, 129.0, 127.9, 127.4, 125.3, 123.3, 122.8,
121.1, 120.9, 112.3, 110.8, 74.5, 49.7, 13.5; HRMS (ESI): m/z calculated
for [M+H]+ C24H22BrN2O 433.0916; found 433.0854.
4.4.28. (E)-5-(((4-bromobenzyl)oxy)imino)-3,4,5,10-tetrahydroazepino
[3,4-b]indol-1(2H)-one (11a)
4.4.21. (E)-1-(1-benzyl-1H-indol-3-yl)ethan-1-one O-benzyl oxime (5u)
Off-white solid; yield 85%; 1H NMR (500 MHz, DMSO‑d6): δ 8.13 (d,
J = 7.8 Hz, 1H), 7.99 (s, 1H), 7.49–7.43 (m, 3H), 7.42–7.36 (m, 2H),
7.35–7.28 (m, 3H), 7.27–7.19 (m, 3H), 7.15 (t, J = 7.7 Hz, 1H), 7.09 (t, J
= 7.3 Hz, 1H), 5.44 (s, 2H), 5.21 (s, 2H), 2.26 (s, 3H); 13C NMR (125
MHz, DMSO‑d6): δ 152.5, 139.1, 138.2, 137.2, 131.3, 129.0, 128.7,
128.4, 128.0, 127.9, 127.4, 125.3, 123.4, 122.8, 120.9, 112.4, 110.8,
75.5, 49.7, 13.5; HRMS (ESI): m/z calculated for [M+H]+ C24H23N2O
355.1810; found 355.1813.
Off-white solid; yield 65%; 1H NMR (500 MHz, DMSO‑d6): δ 11.94 (s,
1H), 8.40 (t, J = 5.1 Hz, 1H), 8.08 (d, J = 7.8 Hz, 1H), 7.59 (d, J = 7.4
Hz, 2H), 7.43–738 (m, 3H), 7.26 (t, J = 7.0 Hz, 1H), 7.10 (t, J = 6.9 Hz,
1H), 5.23 (s, 2H), 3.33–3.28 (m, 2H), 3.07–2.99 (m, 2H); 13C NMR (125
MHz, DMSO‑d6): δ 164.4, 155.5, 138.3, 136.6, 131.7, 131.0, 130.6,
124.9, 124.9, 124.5, 121.4, 121.2, 112.7, 111.4, 75.0, 37.7, 31.2; HRMS
(ESI): m/z calculated for [M+H]+ C19H17BrN3O2 398.0504; found
398.0444.
4.4.22. (E)-1-(1H-indol-2-yl)ethan-1-one O-(4-chlorobenzyl) oxime (7a)
Off-white solid; yield 71%; 1H NMR (500 MHz, DMSO‑d6): δ 11.13
(s, 1H), 7.58 (d, J = 8.4 Hz, 2H), 7.53 (d, J = 7.9 Hz, 1H), 7.45–7.37 (m,
3H), 7.13 (t, J = 7.4 Hz, 1H), 6.98 (t, J = 7.4 Hz, 1H), 6.83 (d, J = 1.6 Hz,
1H), 5.22 (s, 2H), 2.25 (s, 3H); 13C NMR (125 MHz, DMSO‑d6): δ 149.5,
137.9, 137.7, 133.9, 131.7, 130.5, 127.8, 123.4, 121.3, 121.0, 119.7,
112.2, 104.1, 75.0, 12.7; HRMS (ESI): m/z calculated for [M+H]+
C17H16ClN2O 299.0951; found 299.0999.
4.4.29. (E)-5-(((4-chlorobenzyl)oxy)imino)-3,4,5,10-tetrahydroazepino
[3,4-b]indol-1(2H)-one (11b)
Off-white solid; yield 68%; 1H NMR (500 MHz, DMSO‑d6): δ 11.93 (s,
1H), 8.39 (t, J = 5.2 Hz, 1H), 8.08 (d, J = 8.1 Hz, 1H), 7.50 –7.43 (m,
5H), 7.26 (t, J = 7.6 Hz, 1H), 7.10 (t, J = 7.5 Hz, 1H), 5.25 (s, 2H),
3.33–3.29 (m, 2H), 3.07–2.99 (m, 2H); 13C NMR (125 MHz, DMSO‑d6): δ
164.4, 155.5, 137.8, 136.6, 132.7, 131.0, 130.3, 128.7, 125.0, 124.9,
124.5, 121.4, 112.7, 111.4, 74.9, 37.7, 31.2; HRMS (ESI): m/z calculated
for [M+H]+ C19H17ClN3O2 354.1009; found 354.0957.
4.4.23. (E)-1-(1H-indol-2-yl)ethan-1-one O-(4-bromobenzyl) oxime (7b)
Off-white solid; yield 73%; 1H NMR (500 MHz, DMSO‑d6): δ 11.13 (s,
9