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(br s, 1H), 8.40 (d, J ¼ 2.5 Hz, 1H), 7.79 (s, 1H), 7.64 (m, 2H),
7.55 (d, J ¼ 8.8 Hz, 1H), 7.47 (m, 3H), 7.10 (dd, J ¼ 8.8,
2.5 Hz, 1H), 4.85 (t, J ¼ 5.3 Hz, 1H), 4.51 (t, J ¼ 5.4 Hz,
2H), 3.77 (m, 2H). Anal. C22H16N2O4$3/4H2O (C, H), N:
calcd, 7.26; found, 6.76.
4.54 (t, J ¼ 5.2 Hz, 2H), 3.91 (s, 3H), 3.77 (m, 2H). Anal.
C23H16Cl2N2O4 (C, H, N).
5.1.11. 4-(2,6-Dichlorophenyl)-9-hydroxy-6-(2-hydroxy-
ethyl)pyrrolo[3,4-c]carbazole-1,3(2H,6H )-dione (14)
Demethylation of 77c (0.10 g, 0.22 mmol) with BBr3, fol-
lowing Procedure 4, gave 14 (49 mg, 50%) as an orange/yellow
5.1.8. 4-(2-Chlorophenyl)-6-(2-hydroxyethyl)-9-methoxypy-
rrolo[3,4-c]carbazole-1,3(2H,6H )-dione (77b)
1
powder; mp 254e257 ꢀC. H NMR [(CD3)2SO] d 11.10 (br s,
Alkylation of 2-[(E,Z )-2-(2-chlorophenyl)ethenyl]-5-me-
thoxy-1H-indole (70b) [9] (1.92 g, 6.77 mmol) with sodium
hydride (0.39 g of 60% dispersion in mineral oil, 8.12 mmol)
and 2-(2-bromoethoxy)tetrahydro-2H-pyran (1.56 g, 7.44
mmol) following Procedure 1, gave crude 2-[(E,Z )-2-(2-
chlorophenyl)ethenyl]-5-methoxy-1-[2-(tetrahydro-2H-pyran-2-
yloxy)ethyl]-1H-indole (75b) which was dissolved in MeOH/
THF (1:1, 120 mL) and treated with 2 N HCl (15 mL), stirring
at room temperature for 3 h. The solution was then diluted with
saturated aqueous NaHCO3 and concentrated under reduced
pressure to precipitate crude 2-{2-[(E,Z )-2-(2-chlorophenyl)
ethenyl]-5-methoxy-1H-indol-1-yl}ethanol (76b) (1.90 g,
86%), which was collected by filtration and dried in vacuo.
This solid was reacted directly with maleimide and aromatised
with MnO2 for 18 h, following Procedure 2 described above, to
give 77b (72%) as a yellow powder; mp 255e257 ꢀC. 1H NMR
[(CD3)2SO] d 11.10 (br s, 1H), 8.52 (d, J ¼ 2.6 Hz, 1H), 7.80 (s,
1H), 7.71 (d, J ¼ 9.0 Hz, 1H), 7.59e7.56 (m, 1H), 7.52e7.43
(m, 4H), 7.29 (dd, J ¼ 9.0, 2.6 Hz, 1H), 4.84 (t, J ¼ 5.0 Hz,
1H), 4.53 (t, J ¼ 5.2 Hz, 2H), 3.90 (s, 3H), 3.77 (m, 2H). Anal.
C23H17ClN2O4 (C, H, N).
1H), 9.35 (s, 1H), 8.36 (d, J ¼ 2.4 Hz, 1H), 7.80 (s, 1H), 7.61
(m, 3H), 7.50 (dd, J ¼ 8.7, 7.3 Hz, 1H), 7.13 (dd, J ¼ 8.8,
2.4 Hz, 1H), 4.82 (t, J ¼ 5.5 Hz, 1H), 4.49 (t, J ¼ 5.2 Hz, 2H),
3.75 (m, 2H). Anal. C22H14Cl2N2O4$1/2H2O (C, H, N).
5.1.12. 6-(3-Hydroxypropyl)-9-methoxy-4-phenylpyrrolo-
[3,4-c]carbazole-1,3(2H,6H )-dione (73a)
Alkylation of 5-methoxy-2-[(E,Z )-2-phenylethenyl]-1H-in-
dole (70a) [10] (6.85 g, 27.5 mmol) with 3-bromopropoxy-
tert-butyldimethylsilane, following Procedure 1, gave crude
1-(3-{[tert-butyl(dimethyl)silyl]oxy}propyl)-5-methoxy-2-
[(E,Z )-2-phenylethenyl]-1H-indole (71a) which was reacted
successively with maleimide and DDQ following Procedures
2 and 5, respectively, to give crude 6-(3-{[tert-butyl(dimethyl)-
silyl]oxy}propyl)-9-methoxy-4-phenylpyrrolo[3,4-c]carbazole-
1,3(2H,6H )-dione. This product was dissolved in MeOH
(300 mL) containing 1 N HCl (50 mL), and the solution was
kept at room temperature for 3 h, then partitioned between water
and EtOAc. The organic layer was dried and evaporated, and the
residue was chromatographed on silica gel, eluting with CH2Cl2
to CH2Cl2/EtOAc (7:3), to give 73a (2.55 g, 23%); mp (Et2O)
241e243 ꢀC. 1H NMR [(CD3)2SO] d 11.10 (br s, 1H), 8.56 (d,
J ¼ 2.6 Hz, 1H), 7.82 (s, 1H), 7.67 (m, 3H), 7.47 (m, 3H),
7.30 (dd, J ¼ 9.0, 2.6 Hz, 1H), 4.66 (t, J ¼ 4.9 Hz, 1H), 4.55
(t, J ¼ 6.9 Hz, 2H), 3.90 (s, 3H), 3.39 (m, 2H), 1.93 (m, 2H).
Anal. C24H20N2O4 (C, H, N).
5.1.9. 4-(2-Chlorophenyl)-6-(2-hydroxyethyl)-
9-hydroxypyrrolo[3,4-c]carbazole-1,3(2H,6H )-dione (13)
Deprotection of 77b with BBr3, following Procedure 4, gave
13 (87%) as a yellow/orange powder; mp 265 ꢀC (dec). 1H NMR
[(CD3)2SO] d 11.04 (br s, 1H), 9.33 (br s, 1H), 8.38 (d,
J ¼ 2.4 Hz, 1H), 7.75 (s, 1H), 7.60e7.56 (m, 2H), 7.52e7.43
(m, 4H), 7.12 (dd, J ¼ 8.8, 2.4 Hz, 1H), 4.83 (t, J ¼ 5.5 Hz,
1H), 4.49 (t, J ¼ 5.2 Hz, 2H), 3.77 (dt, J ¼ 5.5, 5.2 Hz, 2H).
Anal. C22H15ClN2O4$1/2H2O (C, H, N).
5.1.13. 9-Hydroxy-6-(3-hydroxypropyl)-
4-phenylpyrrolo-[3,4-c]carbazole-1,3(2H,6H )-dione (15)
Demethylation of 73a (60 mg, 0.15 mmol) with BBr3 at
room temperature for 3 h, following Procedure 4, gave 15
(45 mg, 78%); mp 274e276 ꢀC. 1H NMR [(CD3)2SO]
d 11.05 (br s, 1H), 9.33 (s, 1H), 8.41 (d, J ¼ 2.4 Hz, 1H),
7.77 (s, 1H), 7.64 (m, 2H), 7.56 (d, J ¼ 8.8 Hz, 1H), 7.46
(m, 3H), 7.12 (dd, J ¼ 8.8, 2.4 Hz, 1H), 4.64 (t, J ¼ 4.9 Hz,
1H), 4.51 (t, J ¼ 6.9 Hz, 2H), 3.39 (m, 2H), 1.92 (m, 2H).
Anal. C23H18N2O4 (C, H, N).
5.1.10. 4-(2,6-Dichlorophenyl)-6-(2-hydroxyethyl)-9-metho-
xypyrrolo[3,4-c]carbazole-1,3(2H,6H )-dione (77c)
Alkylation of 2-[(E )-2-(2,6-dichlorophenyl)ethenyl]-5-
methoxy-1H-indole (70c) [9] (3.0 g, 10.6 mmol) with 2-(2-
bromoethoxy)tetrahydro-2H-pyran, according to Procedure 1,
gave crude 2-[(E )-2-(2,6-dichlorophenyl)ethenyl]-5-methoxy-
1-[2-(tetrahydro-2H-pyran-2-yloxy)ethyl]-1H-indole
(75c).
5.1.14. 4-(2,6-Dichlorophenyl)-6-(3-hydroxypropyl)-
Treatment of this with 2 N HCl in MeOH/THF, following Pro-
cedure 3, gave crude 2-{2-[(E )-2-(2,6-dichlorophenyl)
ethenyl]-5-methoxy-1H-indol-1-yl}ethanol (76c) which was
reacted directly with maleimide (1.26 g) according to Proce-
dure 2 and aromatised with DDQ following Procedure 5. Trit-
uration in MeOH then gave 77c as a yellow solid (2.14 g,
9-methoxypyrrolo[3,4-c]carbazole-1,3(2H,6H )-dione (73c)
Alkylation of 2-[(E )-2-(2,6-dichlorophenyl)ethenyl]-5-me-
thoxy-1H-indole (70c) [9] (3.0 g, 9.43 mmol) with 3-bromo-
propoxy-tert-butyldimethylsilane, according to Procedure 1,
gave crude 1-(3-{[tert-butyl(dimethyl)silyl]oxy}propyl)-2-[(E )-
2-(2,6-dichlorophenyl)ethenyl]-5-methoxy-1H-indole
(71c)
1
44%); mp 229e231 ꢀC. H NMR [(CD3)2SO] d 11.17 (br s,
which was dissolved in MeOH/CH2Cl2 (3:1, 300 mL) and
treated with 1 N HCl (60 mL). This solution was stirred at
room temperature for 2 h, then diluted with saturated
aqueous NaHCO3 and concentrated under reduced pressure
1H), 8.50 (d, J ¼ 2.6 Hz, 1H), 7.86 (s, 1H), 7.72 (d,
J ¼ 9.0 Hz, 1H), 7.62 (m, 2H), 7.51 (dd, J ¼ 8.9, 7.4 Hz,
1H), 7.31 (dd, J ¼ 9.0, 2.6 Hz, 1H), 4.83 (t, J ¼ 5.3 Hz, 1H),