May 2011
591
tert-Butyl [4-(4-Benzyl-5-bromo-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48i) Treat-
ments of 43ai (440 mg, 0.85 mmol) with TBABr3 (408 mg, 0.85 mmol) car-
ried out in the same manner as described for 48a gave 48i (444 mg, 88%) as
a white solid after purification by column chromatography (SiO2, C6H14/
EtOAcꢁ4/1—2/1). IR (ATR): 3384, 2951, 1710, 1631, 1566, 1250, 1153,
1072, 826, 710 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.25 (9H, s), 0.55—0.59 (2H,
m), 1.56 (9H, s), 3.15 (2H, t, Jꢁ7.6 Hz), 3.85 (2H, br s), 5.78 (2H, br s), 6.71
(1H, br s), 7.12—7.25 (5H, m), 7.37 (1H, d, Jꢁ5.5 Hz), 8.20 (1H, br s).
LR-MS (ESIꢄ) m/z: 598 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for
C28H37BrN5O3Si (MꢄHꢄ) 598.18490, Found 598.18466.
tert-Butyl [4-(4-Benzyl-3,5-dibromo-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48j) Treat-
ments of 48i (200 mg, 0.33 mmol) with TBABr3 (182 mg, 0.38 mmol) car-
ried out in a similar manner to that described for 48a gave 48j (211 mg,
93%) as a white solid after purification by column chromatography (SiO2,
C6H14/EtOAcꢁ2/1). IR (ATR): 3372, 2950, 1710, 1635, 1569, 1250, 1147,
1060, 834 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.22 (9H, br s), 0.55 (2H, t, Jꢁ8.3
Hz), 1.56 (9H, s), 3.08 (2H, br s), 3.92 (2H, br s), 5.40 (2H, br s), 7.15 (1H, t,
Jꢁ7.3 Hz), 7.23 (2H, t, Jꢁ7.3 Hz), 7.30 (2H, d, Jꢁ7.3 Hz), 7.51 (1H, d, Jꢁ
5.5 Hz), 8.30 (1H, br s). LR-MS (ESIꢄ) m/z: 676 [MꢄHꢄ]. HR-MS (ESIꢄ)
m/z: Calcd for C28H36Br2N5O3Si (MꢄHꢄ) 676.09542, Found 676.09520.
tert-Butyl [4-(5-Bromo-4-phenethyl-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48k) The
same treatments of 47a (299 mg, 0.56 mmol) with TBABr3 (284 mg, 0.59
mmol) as those described for 48a gave 48k (290 mg, 91%) as a pale yellow
amorphous solid after purification by column chromatography (SiO2, C6H14/
EtOAcꢁ5/1—4/1). IR (ATR): 3391, 2949, 1713, 1630, 1567, 1248, 1153,
1087, 859, 833, 697 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.26 (9H, s), 0.54—0.58
(2H, m), 1.57 (9H, s), 2.79 (2H, br s), 2.90 (2H, t, Jꢁ7.6 Hz), 3.09—3.13
(2H, m), 5.76 (2H, br s), 6.66 (1H, br s), 7.11—7.15 (1H, m), 7.20—7.26
(4H, m), 7.39 (1H, d, Jꢁ5.5 Hz), 8.17 (1H, d, Jꢁ5.5 Hz). LR-MS (ESIꢄ)
m/z: 612 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for C29H39BrN5O3Si (MꢄHꢄ)
612.20055, Found 612.20057.
pale yellow amorphous solid after purification by column chromatography
(SiO2, C6H14/EtOAcꢁ1/1). IR (KBr): 3383, 2954, 1721, 1637, 1574, 1513,
1
1472, 1370, 1250, 1157, 1089, 861, 834, 770 cmꢃ1. H-NMR (CD3OD) d:
ꢃ0.22 (9H, s), 0.56 (2H, t, Jꢁ8.3 Hz), 1.57 (9H, s), 3.09 (2H, br s), 5.39
(2H, br s), 7.54 (1H, d, Jꢁ5.2 Hz), 8.31 (1H, br s). LR-MS (ESIꢄ) m/z: 664
[MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for C21H29Br3N5O3Si (MꢄHꢄ)
663.95898, Found 663.95572.
tert-Butyl [4-(4,5-Dichloro-1-(2-(trimethylsilyl)ethoxymethyl)-1H-
pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48c) To a solu-
tion of 43ac (274 mg, 0.64 mmol) in THF (7.0 ml) was added NCS (170 mg,
1.3 mmol). The mixture was stirred at room temperature for 2 d, and concen-
trated in vacuo. The residue was purified by column chromatography (SiO2,
C6H14/EtOAcꢁ4/1—3/1) to give 48c (59.6 mg, 19%) as a pale yellow amor-
phous solid. IR (ATR): 3383, 2952, 1714, 1629, 1568, 1481, 1248, 1152,
1078, 859, 832, 768 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.25 (9H, s), 0.59 (2H, t,
Jꢁ8.1 Hz), 1.57 (9H, s), 3.17 (2H, t, Jꢁ8.1 Hz), 5.83 (2H, br s), 6.91 (1H,
br s), 7.41 (1H, d, Jꢁ5.5 Hz), 8.22 (1H, br s). LR-MS (ESIꢄ) m/z: 498
[MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for C21H30Cl2N5O3Si (MꢄHꢄ)
498.14950, Found 498.14982.
tert-Butyl [4-(4-Bromo-5-chloro-1-(2-(trimethylsilyl)ethoxymethyl)-1H-
pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48d) Treatments
of 43ad (218 mg, 0.42 mmol) with NCS (56.2 mg, 0.42 mmol) carried out in
the same manner as described for 48c gave 48d (209 mg, 91%) as a light
brown amorphous solid after purification by column chromatography (SiO2,
C6H14/EtOAcꢁ1/1). IR (ATR): 3382, 2951, 1715, 1629, 1568, 1476, 1248,
1152, 1079, 858, 832, 768 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.25 (9H, s), 0.59
(2H, t, Jꢁ8.1 Hz), 1.57 (9H, s), 3.17 (2H, t, Jꢁ8.1 Hz), 5.84 (2H, br s), 6.95
(1H, br s), 7.41 (1H, d, Jꢁ5.5 Hz), 8.23 (1H, br s). LR-MS (ESIꢄ) m/z: 542
[MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for C21H30BrClN5O3Si (MꢄHꢄ)
542.09898, Found 542.09858.
tert-Butyl 4-(3,4-Dibromo-5-methyl-1-(2-(trimethylsilyl)ethoxymethyl)-
1
H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48e) Treat-
ments of 43ae (100 mg, 0.19 mmol) with TBABr3 (101 mg, 0.21 mmol) car-
ried out in the same manner as described for 48a gave 48e (113 mg, 98%) as
a colorless amorphous solid after purification by column chromatography
(SiO2, C6H14/EtOAcꢁ3/1—2/1). IR (ATR): 3376, 2952, 1718, 1634, 1568,
1248, 1151, 1077, 859, 830 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.24 (9H, s), 0.53
(2H, t, Jꢁ8.3 Hz), 1.57 (9H, s), 2.40 (3H, s), 2.99 (2H, br s), 5.29 (2H, br s),
7.52 (1H, d, Jꢁ5.5 Hz), 8.31 (1H, br s). LR-MS (ESIꢄ) m/z: 600 [MꢄHꢄ].
HR-MS (ESIꢄ) m/z: Calcd for C22H32Br2N5O3Si (MꢄHꢄ) 600.06412, Found
600.06419.
tert-Butyl [4-(3,5-Dibromo-4-phenethyl-1-(2-(trimethylsilyl)etho-
xymethyl)-1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate
(48l) Similar treatments of 48k (100 mg, 0.16 mmol) with TBABr3 (86.3
mg, 0.18 mmol) to those described for 48a gave 48l (111 mg, 98%) as a col-
orless amorphous solid after purification by column chromatography (SiO2,
C6H14/EtOAcꢁ4/1—3/1). IR (ATR): 3378, 2950, 1718, 1634, 1571, 1249,
1152, 1075, 831, 697 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.23 (9H, s), 0.54 (2H,
t, Jꢁ8.3 Hz), 1.57 (9H, s), 2.84 (4H, br s), 3.03 (2H, br s), 5.36 (2H, br s),
7.14—7.18 (1H, m), 7.21—7.28 (4H, m), 7.52 (1H, d, Jꢁ5.5 Hz), 8.32 (1H,
br s). LR-MS (ESIꢄ) m/z: 690 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for
C29H38Br2N5O3Si (MꢄHꢄ) 690.11107, Found 690.11073.
tert-Butyl [4-(5-Bromo-4-methyl-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48f) Treat-
ments of 43ag (221 mg, 0.50 mmol) with TBABr3 (265 mg, 0.55 mmol) car-
ried out in a similar manner to that described for 48a gave 48f (211 mg,
81%) as a pale yellow amorphous solid after purification by column chro-
matography (SiO2, C6H14/EtOAcꢁ5/1—4/1). IR (ATR): 3392, 2951, 1714,
tert-Butyl [4-(3,5-Dibromo-4-(2-(trifluoromethyl)phenethyl)-1-(2-
(trimethylsilyl)ethoxymethyl)-1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-
2-yl]carbamate (48m) Treatments of 47b (380 mg, 0.63 mmol) with TBABr3
(641 mg, 1.3 mmol) carried out in the same manner as described for 48a
gave 48m (447 mg, 93%) as a pale yellow amorphous solid after purification
by column chromatography (SiO2, C6H14/EtOAcꢁ4/1—3/1). IR (ATR):
1
1630, 1567, 1248, 1153, 1087, 859, 833, 766 cmꢃ1. H-NMR (CD3OD) d:
ꢃ0.26 (9H, s), 0.56 (2H, t, Jꢁ8.3 Hz), 1.57 (9H, s), 2.11 (3H, s), 3.12 (2H,
t, Jꢁ8.3 Hz), 5.74 (2H, br s), 6.73 (1H, br s), 7.38 (1H, d, Jꢁ5.5 Hz), 8.22
(1H, br s). LR-MS (ESIꢄ) m/z: 522 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for
C22H33BrN5O3Si (MꢄHꢄ) 522.15360, Found 522.15388.
3376, 2952, 1718, 1571, 1311, 1249, 1151, 1121, 831 cmꢃ1 1H-NMR
.
(CD3OD) d: ꢃ0.23 (9H, s), 0.55 (2H, t, Jꢁ8.1 Hz), 1.57 (9H, s), 2.85 (2H,
br s), 3.06 (4H, br s), 5.37 (2H, br s), 7.34—7.42 (2H, m), 7.52—7.55 (2H,
m), 7.65 (2H, d, Jꢁ7.6 Hz), 8.33 (1H, br s). LR-MS (ESIꢄ) m/z: 758 [Mꢄ
Hꢄ]. HR-MS (ESIꢄ) m/z: Calcd for C30H37Br2F3N5O3Si (MꢄHꢄ)
758.09845, Found 758.09866.
tert-Butyl [4-(3,5-Dibromo-4-(3-(trifluoromethyl)phenethyl)-1-(2-
(trimethylsilyl)ethoxymethyl)-1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-
2-yl]carbamate (48n) Treatments of 47c (345 mg, 0.57 mmol) with TBABr3
(579 mg, 1.2 mmol) carried out in a similar manner to that described for 48a
gave 48n (339 mg, 78%) as a pale yellow amorphous solid after purification
by column chromatography (SiO2, C6H14/EtOAcꢁ4/1—3/1). IR (ATR):
3379, 2952, 1718, 1571, 1329, 1250, 1154, 1124, 1072, 832 cmꢃ1. 1H-NMR
(CD3OD) d: ꢃ0.24 (9H, s), 0.53 (2H, t, Jꢁ8.3 Hz), 1.57 (9H, s), 2.87 (2H,
br s), 3.01 (4H, br s), 5.36 (2H, br s), 7.44—7.53 (5H, m), 8.32 (1H, br s).
LR-MS (ESIꢄ) m/z: 758 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for
C30H37Br2F3N5O3Si (MꢄHꢄ) 758.09845, Found 758.09875.
tert-Butyl 4-(3,5-Dibromo-4-methyl-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48g) The
same treatments of 48f (100 mg, 0.19 mmol) with TBABr3 (101 mg, 0.21
mmol) as those described for 48a gave 48g (108 mg, 94%) as a colorless
amorphous solid after purification by column chromatography (SiO2, C6H14/
EtOAcꢁ3/1). IR (ATR): 3378, 2951, 1718, 1634, 1569, 1248, 1152, 1068,
858, 830 cmꢃ1. 1H-NMR (CD3OD) d: ꢃ0.24 (9H, s), 0.54 (2H, t, Jꢁ8.3 Hz),
1.57 (9H, s), 2.11 (3H, br s), 3.05 (2H, br s), 5.37 (2H, br s), 7.51 (1H, d, Jꢁ
5.5 Hz), 8.31 (1H, br s). LR-MS (ESIꢄ) m/z: 600 [MꢄHꢄ]. HR-MS (ESIꢄ)
m/z: Calcd for C22H32Br2N5O3Si (MꢄHꢄ) 600.06412, Found 600.06447.
tert-Butyl [4-(5-Bromo-4-phenyl-1-(2-(trimethylsilyl)ethoxymethyl)-
1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-2-yl]carbamate (48h) Simi-
lar treatments of 43ah (151 mg, 0.30 mmol) with TBABr3 (151 mg,
0.31 mmol) to those described for 48a gave 48h (167 mg, 96%) as a white
powder after purification by column chromatography (SiO2, C6H14/EtOAcꢁ
4/1). mp: 157—159 °C (from C6H14–EtOAc). IR (KBr): 3404, 2964, 1705,
1637, 1561, 1474, 1269, 1253, 1155, 1087, 859, 835, 755, 697 cmꢃ1 1H-
.
tert-Butyl [4-(3,5-Dibromo-4-(4-(trifluoromethyl)phenethyl)-1-(2-
(trimethylsilyl)ethoxymethyl)-1H-pyrrol-2-yl)-1H-imidazo[4,5-c]pyridin-
2-yl]carbamate (48o) The same treatments of 47d (259 mg, 0.43 mmol)
with TBABr3 (435 mg, 0.90 mmol) as those described for 48a gave 48o
(256 mg, 78%) as a pale yellow amorphous solid after purification by col-
umn chromatography (SiO2, C6H14/EtOAcꢁ4/1). IR (ATR): 3390, 2926,
NMR (CD3OD) d: ꢃ0.24 (9H, s), 0.61 (2H, t, Jꢁ7.9 Hz), 1.57 (9H, s), 3.20
(2H, t, Jꢁ7.9 Hz), 5.89 (2H, br s), 7.07 (1H, br s), 7.27 (1H, t, Jꢁ7.3 Hz),
7.39 (2H, t, Jꢁ7.3 Hz), 7.43 (1H, d, Jꢁ5.5 Hz), 7.64—7.67 (2H, m), 8.26
(1H, br s). LR-MS (ESIꢄ) m/z: 584 [MꢄHꢄ]. HR-MS (ESIꢄ) m/z: Calcd for
C27H35BrN5O3Si (MꢄHꢄ) 584.16925, Found 584.16867.