M. Scholz et al. / Bioorg. Med. Chem. 20 (2012) 4830–4837
4835
1733 (s,
4.1.2.2.6. 1-(1-Carboxy-1,7-dicarba-closo-dodecaboran(12)yl)-5-
methoxy-2-methyl-1H-indole-3-acetic acid benzyl ester
(2m). Yield: 0.53 g (86% from 0.40 g 2); elemental Anal. Calcd
for C22H29B10NO4: C, 55.10; H, 6.09. Found: C, 54.70; H, 6.13;
mp: 57–58 °C; ESI MS (+) (CH3COCH3/CHCl3/Na+): m/z: 537.1
(100%, [M+CH3COCH3]+); 1H NMR (CDCl3, ppm): 7.31–7.26 (vbr,
6H, CHaromat together with solvent residual peak), 6.91 (s, 1H,
CHaromat), 6.82 (d, 1JHH = 8 Hz, 1H, CHaromat), 5.11 (s, 2H, CH2 benzyl),
m
(C@O)).
4.1.2.2.9. 1-(1-Carboxy-1,2-dicarba-closo-dodecaboran(12)yl)-5-
methoxy-2-methyl-1H-indole-3-acetic acid tert-butyl ester
(3o). Yield: 0.37 g (76% from 0.30 g 3); elemental Anal. Calcd
for C19H31B10NO4: C, 51.22; H, 7.01. Found: C, 51.54; H, 6.99;
mp: 109–110 °C; ESI MS (+) (CH3COCH3): m/z: 485.3 (100%,
3
[M+K]+); 1H NMR (CDCl3, ppm): 7.31 (d, JHH = 8 Hz, 1H, CHindole),
4
3
4
6.95 (d, JHH = 2 Hz, 1H, CHindole), 6.85 (dd, JHH = 8 Hz, JHH = 2 Hz,
1H, CHindole), 4.37 (s, 1H, CclusterH), 3.85 (s, 3H, OCH3), 3.52 (s, 2H,
CH2), 3.20–1.50 (m, vbr, 10H, C2H10B10), 2.31 (s, 3H, CH3), 1.41 (s,
1
3.77 (s, 3H, OCH ), 3.66 (s, 2H, CH2), 3.05 (s, 1H, CclusterH), 3.50–1.50
9H, C(CH3)3); 11B NMR (CDCl3, ppm): ꢁ1.2 (d, JBH = 180 Hz, 1B,
3
(m, vbr, 10H, C2H10B10), 2.26 (s, 3H, CH3); 11B NMR (CDCl3, ppm):
ꢁ4.8 (vbr, 1B, C2H10B10), ꢁ5.8 (vbr, 1B, C2H10B10), ꢁ10.5 (d,
1JBH = 154 Hz, 4B, C2H10B10), ꢁ13.1 (d, 1JBH = 180 Hz, 2B,
C2H10B10), ꢁ15.3 (vbr, 2B, C2H10B10); 13C NMR (CDCl3, ppm):
170.7 (s, vbr, CO), 167.3 (s, CO), 155.5 (s, vbr, CindoleO), 135.7 (s,
C2H10B10), ꢁ2.6 (d, 1B, C2H10B10), ꢁ8.5 (d, JBH = 154 Hz, 2B,
1
C2H10B10), ꢁ11.9 (vbr, 3B, C2H10B10), ꢁ13.1 (vbr, 3B, C2H10B10);
13C NMR (CDCl3, ppm): 169.9 (s, vbr, CO), 166.5 (s, CO), 155.9 (s,
vbr, CindoleO), 134.8 (s, vbr, Cindole), 130.2 (s, vbr, Cindole), 130.1 (s,
1
vbr, Cindole), 113.2 (d, JCH = 161 Hz, CindoleH), 112.1 (s, vbr, Cindole),
Caromat), 134.9 (s, Caromat), 130.4 (s, vbr, Caromat), 129.4 (s, vbr,
112.0 (dd, 1JCH = 161 Hz, 2JCH = 5 Hz, CindoleH), 101.5 (dd,
2
Caromat), 128.5 (m, vbr, CHphenyl), 128.2 (m, vbr, CHphenyl), 128.0
1JCH = 161 Hz, JCH = 5 Hz, CindoleH), 81.2 (s, vbr, C(CH3)3), 74.6 (s,
1
1
1
(m, vbr, CHphenyl), 112.8 (d, JCH = 161 Hz, CindoleH), 112.0 (dd,
vbr, Ccluster), 59.3 (d, JCH = 191 Hz, CclusterH), 55.7 (q, JCH = 151 Hz,
2
1
1
1JCH = 161 Hz, JCH = 5 Hz, CindoleH), 109.8 (s, vbr, Caromat), 101.0
OCH3), 31.9 (t, JCH = 131 Hz, CH2), 28.0 (q, vbr, JCH = 131 Hz,
1
2
1
(dd, JCH = 161 Hz, JCH = 5 Hz, CindoleH), 78.1 (s, Ccluster), 66.7 (t,
C(CH3)3), 11.4 (q, JCH = 131 Hz, CH3); IR (selected, KBr, cmꢁ1):
1JCH = 151 Hz, OCH2), 55.7 (q, JCH = 141 Hz, OCH3), 55.0 (d,
= 3080 (w), 3004 (w), 2978 (w), 2930 (w), 2831 (w), 2656 (w),
1
~
m
1JCH = 181 Hz, CclusterH), 30.5 (t, JCH = 131 Hz, CH2), 11.3 (q,
2574 (m, m(B–H)), 1731 (s, m(C@O)), 1719 (s, m(C@O)).
1
1JCH = 131 Hz, CH3); IR (selected, KBr, cmꢁ1):
= 3061 (w), 2996
4.1.2.2.10. 1-(1-Carboxy-1,7-dicarba-closo-dodecaboran(12)yl)-5-
methoxy-2-methyl-1H-indole-3-acetic acid tert-butyl ester (3m).
Yield: 0.14 g (87% from 0.10 g 3); elemental Anal. Calcd for
~
m
(w), 2925 (w), 2834 (w), 2609 (s, m(B–H)), 1733 (s, m(C@O)).
4.1.2.2.7. 1-(1-Carboxy-1,12-dicarba-closo-dodecaboran(12)yl)-5-
methoxy-2-methyl-1H-indole-3-acetic acid benzyl ester (2p). Yield:
0.30 g (97% from 0.20 g 2); elemental Anal. Calcd for C22H29B10NO4:
C, 55.10; H, 6.09. Found: C, 54.70; H, 6.13; mp: 77–78 °C; ESI MS
(+) (CH3COCH3): m/z: 537.3 (100%, [M+CH3COCH3]+); 1H NMR
(CDCl3, ppm): 7.31–7.26 (vbr, 5H, CHphenyl together with solvent
C
19H31B10NO4: C, 51.22; H, 7.01. Found: C, 51.41; H, 7.03; mp:
150–151 °C; ESI MS (+) (CH3COCH3/Na+): m/z: 503.1 (100%,
[M+CH3COCH3]+), 468.1 (29%, [M+Na]+); 1H NMR (CDCl3, ppm):
7.24 (d, JHH = 8 Hz, 1H, CHindole), 6.94 (d, JHH = 2 Hz, 1H, CHindole),
3
4
3
4
6.82 (dd, JHH = 8 Hz, JHH = 2 Hz, 1H, CHindole), 3.85 (s, 3H, OCH3),
3.51 (s, 2H, CH2), 3.06 (s, 1H, CclusterH), 3.30–1.40 (m, vbr, 10H,
C2H10B10), 2.27 (s, 3H, CH3), 1.41 (s, 9H, C(CH3)3); 11B NMR (CDCl3,
ppm): ꢁ4.7 (d, 1JBH = 154 Hz, 1B, C2H10B10), ꢁ5.9 (d, 1B, C2H10B10),
3
residual peak), 7.13 (d, 1H, JCH = 8 Hz, CHindole), 6.88 (d,
3
4
4JHH = 2 Hz, 1H, CHindole), 6.79 (dd, 1H, JCH = 8 Hz, JHH = 2 Hz,
CHindole), 5.11 (s, 2H, CH2 benzyl), 3.76 (s, 3H, OCH3), 3.63 (s, 2H,
CH2), 3.33–1.49 (m, vbr, 10H, C2H10B10), 2.90 (s, 1H, CclusterH),
1
1
ꢁ10.5 (d, JBH = 141 Hz, 4B, C2H10B10), ꢁ13.1 (d, JBH = 180 Hz, 2B,
1
1
2.16 (s, 3H, CH3); 11B NMR (CDCl3, ppm): ꢁ13.0 (d, JBH = 154 Hz,
C2H10B10), ꢁ15.2 (d, JBH = 180 Hz, 2B, C2H10B10); 13C NMR (CDCl3,
1
5B, C2H10B10), ꢁ15.1 (d, JBH = 167 Hz, 5B, C2H10B10); 13C NMR
ppm): 170.2 (s, CO), 167.3 (s, CO), 155.5 (s, vbr, CindoleO), 134.6
(m, vbr, Cindole), 130.4 (m, vbr, Cindole), 129.6 (m, vbr, Cindole),
(CDCl3, ppm): 170.7 (s, vbr, CO), 167.9 (s, CO), 155.3 (s, vbr,
1
1
CindoleO), 135.8 (s, vbr, Caromat), 134.8 (s, vbr, Caromat), 130.5 (s,
112.8 (d, JCH = 161 Hz, CindoleH), 111.7 (dd, JCH = 161 Hz,
2JCH = 6 Hz, CindoleH), 110.7 (m, vbr, Cindole), 101.1 (dd, 1JCH = 161 Hz,
2JCH = 6 Hz, CindoleH), 81.0 (m, vbr, C(CH3)3), 78.2 (vbr, Ccluster), 55.7
vbr, Caromat), 129.1 (s, vbr, Caromat), 128.5 (s, vbr, CHphenyl), 128.2
1
(s, vbr, CHphenyl), 128.0 (s, vbr, CHphenyl), 112.7 (d, JCH = 161 Hz,
1
2
1
1
CindoleH), 111.9 (dd, JCH = 161 Hz, JCH = 5 Hz, CindoleH), 109.3 (s,
(q, JCH = 141 Hz, OCH3), 55.0 (d, vbr, JCH = 181 Hz, CclusterH), 31.9
1
2
1
1
vbr, Cindole), 100.8 (dd, JCH = 161 Hz, JCH = 5 Hz, CindoleH), 85.3 (s,
(t, JCH = 121 Hz, CH2), 28.0 (q, JCH = 131 Hz, C(CH3)3), 11.3 (q,
1
3
1JCH = 131 Hz, CH3); IR (selected, KBr, cmꢁ1):
m
= 3056 (m,
m
m
(C–
(B–
~
vbr, Ccluster), 66.6 (tt, JCH = 141 Hz, JCH = 5 Hz, OCH2), 63.8 (d,
1JCH = 181 Hz, CHcluster), 55.7 (q, JCH = 141 Hz, OCH3), 30.5 (t,
H)), 2978 (s,
m
(C–H)), 2931 (s,
m
(C–H)), 2834 (m), 2609 (s,
1
1JCH = 131 Hz, CH2), 11.2 (q, JCH = 131 Hz, CH3); IR (selected, KBr,
H)), 2066 (m), 1847 (m), 1728 (s,
m(C@O)).
1
cmꢁ1):
= 3060 (w), 2929 (w), 2617 (s,
m
(B–H)), 1727 (s,
m(C@O)).
4.1.2.2.11. 1-(1-Carboxy-1,12-dicarba-closo-dodecaboran(12)yl)-
5-methoxy-2-methyl-1H-indole-3-acetic acid tert-butyl ester (3p).
Yield: 0.16 g (99% from 0.10 g 3); elemental Anal. Calcd for
~
m
4.1.2.2.8. 1-(1-Adamantyl)-5-methoxy-2-methyl-1H-indole-3-ace-
tic acid benzyl ester (2a). Yield: 0.55 g (72% from 0.50 g 2); ele-
mental Anal. Calcd for C30H33NO4: C, 76.41; H, 7.05. Found: C,
76.19; H, 7.05; mp: 108–109 °C; ESI MS (+) (CH3COCH3/Na+): m/
z: 494.3 (100%, [M+Na]+); 1H NMR (CDCl3, ppm): 7.29–7.26 (vbr,
5H, CHphenyl together with solvent residual peak), 7.14 (d,
C19H31B10NO4: C, 51.22; H, 7.01. Found: C, 51.14; H, 7.01; mp:
56–57 °C; ESI MS (+) (CH3COCH3): m/z: 503.3 (100%,
3
[M+CH3COCH3]+); 1H NMR (CDCl3, ppm): 7.12 (d, JHH = 8 Hz, 1H,
4
3
CHindole), 6.91 (d, JHH = 2 Hz, 1H, CHindole), 6.79 (d, JHH = 8 Hz,
4JHH = 2 Hz, 1H, CHindole), 3.84 (s, 3H, OCH3), 3.48 (s, 2H, CH2),
3.35–1.14 (m, vbr, 10H, C2H10B10), 2.89 (s, 1H, CclusterH), 2.18 (s,
3H, CH3), 1.41 (s, 9H, C(CH3)3); 11B NMR (CDCl3, ppm): ꢁ13.0 (d,
1JBH = 154 Hz, 5B, C2H10B10), ꢁ15.1 (d, 1JBH = 180 Hz, 5B,
C2H10B10); 13C NMR (CDCl3, ppm): 170.2 (s, vbr, CO), 167.9 (s,
CO), 155.3 (s, vbr, CindoleO), 134.5 (s, vbr, Cindole), 130.5 (s, vbr, Cin-
4
3JHH = 8 Hz, 1H, CHindole), 6.94 (d, JHH = 2 Hz, 1H, CHindole), 6.79
3
4
(dd, JHH = 8 Hz, JHH = 2 Hz, 1H, CHindole), 5.11 (s, 2H, CH2 benzyl),
3.77 (s, 3H, OCH3), 3.70 (s, 2H, CH2), 2.31 (s, 3H, CH3), 2.05 (s,
vbr, 9H, CH/CH2 adamantyl), 1.72 (s, vbr, 6H, CH2 adamantyl); 13C{1H}
NMR (CDCl3, ppm): 186.0 (CO), 171.2 (CO), 154.8 (CindoleO), 135.9
(Caromat), 134.4 (Caromat), 130.2 (Caromat), 129.3 (Caromat), 128.5
(CHphenyl), 128.2 (CHphenyl), 128.0 (CHphenyl), 112.6 (CindoleH),
111.5 (CindoleH), 107.7 (Caromat), 100.6 (CindoleH), 66.6 (OCH2), 55.7
(OCH3), 46.6 (Cadamantyl), 39.3 (CH2 adamantyl), 36.2 (CH2 adamantyl),
30.6 (CH2), 28.0 (CH adamantyl), 11.8 (CH3); IR (selected, KBr,
~
1
dole), 129.3 (s, vbr, Cindole), 112.7 (d, JCH = 161 Hz, CindoleH), 111.6
1
2
(dd, JCH = 161 Hz, JCH = 6 Hz, CindoleH), 110.2 (s, vbr, Cindole),
1
2
100.9 (dd, JCH = 161 Hz, JCH = 6 Hz, CindoleH), 85.4 (s, vbr, Ccluster),
1
80.9 (s, vbr, C(CH3)3), 63.8 (d, JCH = 181 Hz, CclusterH), 55.7 (q,
cmꢁ1):
m
= 3091 (w), 3062 (w), 3032 (w), 3005 (w), 2907 (s,
m(C–
1JCH = 141 Hz, OCH3), 31.9 (t, JCH = 121 Hz, CH2), 28.0 (q, vbr,
1
1
H)), 2850 (m), 2680 (w), 2658 (w), 2346 (w), 2067 (w), 1958 (w),
1879 (w), 1854 (w), 1831 (w), 1802 (w), 1734 (s, (C@O)), 1709
(s, (C@O)).
1JCH = 131 Hz, C(CH3)3), 11.2 (q, JCH = 131 Hz, CH3); IR (selected,
KBr, cmꢁ1):
1728 (s,
= 3059 (w), 2925 (m,
m
(C–H)), 2617 (s,
m
(B–H)),
~
m
m
m
m
(C@O)).