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was around 8. The compound was then extracted using EtOAc and
3.11. Synthesis of compound 5b: 3-(4-methoxybenzyl)-2-
the EtOAc fraction was then washed with water, dried over sodium
sulfate, concentrated and purified using column chromatography
(4% MeOH/ dichloromethane) to afford the compound 3b
(315 mg, 45%). 1H NMR (400 MHz, MeOD) d 9.07 (s, 1H), 8.44 (d,
J = 6.9 Hz, 1H), 8.18–8.16 (m, 1H), 8.16–8.15 (m, 1H), 8.11–8.06
(m, 1H), 7.72–7.62 (m, 2H), 7.60–7.52 (m, 3H). 13C NMR
phenyl-3H-imidazo[4,5-c]quinoline
To a solution of 3b (50 mg, 0.2 mmol) in 1 mL of anhydrous THF,
were added DBU (62 mg, 0.41 mmol) and 1-(chloromethyl)-4-
methoxybenzene (128 mg, 0.82 mmol). The solution was then
heated in a sealed vessel at 80 °C for an hour. After cooling to room
temperature, and removing the solvent under vacuum, the residue
was dissolved in EtOAc and washed with water, dried over sodium
sulfate, concentrated and purified using column chromatography
(8% EtOAc/dichloromethane) to obtain the compound 5b (36 mg,
33%). 1H NMR (400 MHz, CDCl3) d 8.92 (s, 1H), 8.73–8.69 (m, 1H),
8.24–8.20 (m, 1H), 7.82–7.77 (m, 2H), 7.74–7.69 (m, 2H), 7.59–
7.53 (m, 3H), 7.06 (d, J = 8.8 Hz, 2H), 6.90–6.84 (m, 2H), 5.60 (s,
2H), 3.80 (s, 3H). 13C NMR (101 MHz, CDCl3) d 159.52, 154.86,
144.69, 144.54, 136.63, 130.42, 129.67, 129.62, 129.55, 129.11,
129.01, 128.30, 127.66, 127.53, 127.45, 126.86, 122.42, 121.87,
114.64, 55.33, 48.60. MS (ESI) calcd for C24H19N3O, (M+H)+:
366.1601; observed: 366.1491.
(101 MHz, MeOD)
d 143.22, 130.45, 129.06, 128.84, 128.14,
127.48, 126.74, 126.63, 121.39. MS (ESI) calcd for C16H11N3,
(M+H)+: 246.1026; observed: 246.1025.
3.8. Compounds 3c and 3d were synthesized similarly as
described for compound 3b
3c (409 mg, 58%): 1H NMR (500 MHz, MeOD) d 8.93 (s, 1H), 8.25
(s, 1H), 7.98 (t, J = 8.2 Hz, 1H), 7.63–7.52 (m, 2H), 3.02–2.87 (m,
1H), 2.09–2.01 (m, 2H), 1.83 (dd, J = 10.4, 7.3 Hz, 2H), 1.69
(dd, J = 14.8, 8.0 Hz, 1H), 1.67–1.59 (m, 2H), 1.46–1.35 (m, 2H),
1.34–1.22 (m, 1H). 13C NMR (126 MHz, MeOD) d 144.54, 129.56,
128.68, 127.95, 122.57, 40.03, 32.89, 27.16, 26.91. MS (ESI) calcd
for C16H17N3, (M+H)+: 252.1495; observed: 252.1565.
3.12. Compounds 5c and 5d were synthesized similarly as
described for compound 5b
3d (355 mg, 38%): 1H NMR (500 MHz, MeOD) d 8.93 (s, 1H), 8.22
(s, 1H), 8.00 (d, J = 8.5 Hz, 1H), 7.62–7.53 (m, 2H), 2.91 (t, J = 7.7 Hz,
2H), 1.83–1.75 (m, 2H), 1.36–1.22 (m, 4H), 1.14–1.17 (m, 8H), 0.75
(t, J = 6.9 Hz, 3H). 13C NMR (126 MHz, MeOD) d 158.61, 144.52,
129.56, 128.72, 128.00, 122.49, 33.02, 30.55, 30.41, 30.37, 30.32,
29.92, 29.41, 23.74, 14.45. MS (ESI) calcd for C19H25N3, (M+H)+:
296.2121; observed: 296.2178.
5c (9 mg, 12%): 1H NMR (400 MHz, CDCl3) d 8.88 (s, 1H), 8.70–
8.60 (m, 1H), 8.18 (dd, J = 6.6, 2.9 Hz, 1H), 7.72–7.60 (m, 2H), 7.04
(d, J = 8.8 Hz, 2H), 6.92–6.80 (m, 2H), 5.50 (s, 2H), 3.79 (s, 3H), 2.96
(s, 1H), 2.00–1.67 (m, 7H), 1.41 (s, 3H). 13C NMR (101 MHz, CDCl3) d
159.52, 135.86, 129.47, 127.60, 127.07, 126.42, 122.31, 121.95,
114.57, 55.33, 47.06, 36.74, 31.84, 26.25, 25.61. MS (ESI) calcd for
C
24H25N3O, (M+H)+: 372.2070; observed: 372.1990.
3.9. Synthesis of compound 4b: 2-methyl-1-(2-phenyl-3H-
imidazo[4,5-c]quinolin-3-yl)propan-2-ol
5d (21 mg, 30%): 1H NMR (400 MHz, CDCl3) d 8.89 (s, 1H), 8.66–
8.58 (m, 1H), 8.22–8.15 (m, 1H), 7.73–7.62 (m, 2H), 7.05 (d,
J = 8.7 Hz, 2H), 6.91–6.82 (m, 2H), 5.47 (s, 2H), 3.79 (s, 3H), 3.05–
2.95 (m, 2H), 1.87 (dt, J = 15.6, 7.7 Hz, 2H), 1.49–1.38 (m, 2H),
1.33–1.26 (m, 10H), 0.89 (t, J = 6.9 Hz, 3H). 13C NMR (101 MHz,
CDCl3) d 159.57, 156.76, 144.46, 144.11, 135.74, 129.54, 128.59,
127.69, 127.33, 127.14, 126.59, 122.20, 121.75, 114.57, 55.32,
47.36, 31.85, 29.54, 29.42, 29.29, 29.25, 28.28, 27.86, 22.66,
14.11. MS (ESI) calcd for C27H33N3O, (M+H)+: 416.2696; observed:
416.2560.
To a solution of 3b (50 mg, 0.2 mmol) in 1 mL of 2,2-dimethy-
loxirane, was added DBU (62 mg, 0.41 mmol) and the solution
was heated under microwave conditions (600 W, 80 °C, 1 h). After
cooling to room temperature, and removing the solvent under vac-
uum, the residue was dissolved in EtOAc and washed with water,
dried over sodium sulfate, concentrated and purified using column
chromatography (4% MeOH/dichloromethane) to obtain the com-
pound 4b (24 mg, 38%). 1H NMR (400 MHz, MeOD) d 9.34 (s, 1H),
8.65–8.51 (m, 1H), 8.17–8.13 (m, 1H), 7.87–7.79 (m, 2H),
7.78–7.69 (m, 2H), 7.67–7.63 (m, 3H), 4.59 (s, 2H), 1.00 (s, 6H).
13C NMR (101 MHz, MeOD) d 155.90, 143.40, 143.02, 139.02,
130.15, 129.95, 129.85, 129.76, 128.72, 128.04, 127.46, 126.80,
121.65, 121.37, 70.71, 55.09, 26.19. MS (ESI) calcd for C20H19N3O,
(M+H)+: 318.1601; observed: 318.1631.
3.13. Synthesis of compound 6b: 3-(2-phenyl-3H-imidazo[4,5-
c]quinolin-3-yl)propan-1-ol
To a solution of 3b (60 mg, 0.25 mmol) in 2 mL of anhydrous
DMF, were added DBU (62 mg, 0.41 mmol) and 3-bromopropan-
1-ol (139 mg, 1.0 mmol). The solution was then heated in a sealed
vessel at 80 °C for 2 h. After cooling to room temperature, and
removing the solvent under vacuum, the residue was dissolved
in EtOAc and washed with water, dried over sodium sulfate, con-
centrated and purified using column chromatography (20%ace-
tone/dichloromethane) to obtain the compound 6b (13 mg, 18%).
1H NMR (400 MHz, MeOD) d 9.30 (s, 1H), 8.60 (dt, J = 5.0, 2.2 Hz,
1H), 8.21–8.17 (m, 1H), 7.89–7.85 (m, 2H), 7.79–7.71 (m, 2H),
7.67 (dd, J = 4.2, 2.4 Hz, 3H), 4.74–4.60 (m, 2H), 3.55 (t, J = 4.6 Hz,
2H), 2.12–2.03 (m, 2H). 13C NMR (101 MHz, MeOD) d 155.37,
143.79, 143.53, 136.59, 130.46, 129.65, 129.38, 129.15, 128.78,
128.22, 127.59, 126.93, 121.70, 121.40, 58.02, 42.26, 32.70. MS
(ESI) calcd for C19H17N3O, (M+H)+: 304.1444; observed: 304.1440.
3.10. Compounds 4c and 4d were synthesized similarly as
described for compound 4b
4c (42 mg, 65%): 1H NMR (400 MHz, MeOD) d 9.19 (s, 1H), 8.70–
8.56 (m, 1H), 8.14–8.05 (m, 1H), 7.74–7.61 (m, 2H), 4.43 (s, 2H),
3.33 (dt, J = 3.3, 1.6 Hz, 1H), 2.07–1.80 (m, 7H), 1.62–1.42 (m,
3H), 1.32 (s, 6H). 13C NMR (101 MHz, MeOD) d 162.55, 143.37,
143.26, 137.65, 128.97, 127.93, 127.12, 126.50, 121.56, 121.47,
70.32, 53.88, 36.16, 31.55, 26.26, 25.84, 25.53. MS (ESI) calcd for
C
20H25N3O, (M+H)+: 324.2070; observed: 324.2084.
4d (11 mg, 18%): 1H NMR (400 MHz, MeOD) d 9.17 (s, 1H), 8.58
(d, J = 6.4 Hz, 1H), 8.14–8.09 (m, 1H), 7.69 (dd, J = 6.8, 3.2 Hz, 2H),
4.40 (s, 2H), 3.13 (t, J = 6.4 Hz, 2H), 2.02–1.88 (m, 2H), 1.49 (d,
J = 6.3 Hz, 2H), 1.39 (d, J = 15.1 Hz, 2H), 1.38–1.20 (m, 14H), 0.92–
0.86 (m, 3H). 13C NMR (101 MHz, MeOD) d 158.89, 143.39,
143.19, 137.44, 129.30, 127.99, 127.27, 126.65, 121.52, 121.46,
70.72, 54.40, 31.66, 29.27, 29.22, 29.15, 29.05, 27.97, 27.32,
3.14. Compounds 6c and 6d were synthesized similarly as
described for compound 6b
6c (12 mg, 16%): 1H NMR (400 MHz, MeOD) d 9.18 (s, 1H), 8.66–
8.59 (m, 1H), 8.12 (dt, J = 4.8, 2.8 Hz, 1H), 7.72–7.67 (m, 2H), 4.61
(t, J = 7.2 Hz, 2H), 3.64 (dd, J = 12.7, 7.0 Hz, 2H), 3.27–3.16 (m,
26.51, 22.37, 13.24. MS (ESI) calcd for
368.2696; observed: 368.2733.
C
23H33N3O, (M+H)+: