ACCEPTED MANUSCRIPT
7-(N-(1’-Methoxycarbonylethyl)carboxamido)indole (2f) (isolated in a 2/8 mixture of 2f/3f). δH (500
MHz, CDCl3) 10.29 (1 H, brs, indole-NH), 7.83 (1 H, d, 7.8 Hz, Ar-H), 7.48 (1 H, d, 7.8 Hz, Ar-H), 7.34 (1 H,
dd, 3.0 Hz, 2.3 Hz, indole-H), 7.15 (1 H, t, 7.8 Hz, Ar-H), 6.98 (1 H, d, 5.7 Hz, NH), 6.59 (1 H, dd, 3.0 Hz, 2.3
Hz, indole-H), 4.87 (1 H, qi, 7.2 Hz, N-CH) 3.83 (3 H, s, O-CH3), 1.58 (3 H, d, 7.2 Hz, CHCH3). δC (125.7
MHz, CDCl3) 173.7, 167.4, 135.8, 129.6, 129.3, 125.1, 119.3, 118.7, 115.3, 102.0, 52.6, 48.3, 18.6. MS m/z
(rel int.): 246 (48, M+), 187 (9), 171 (5), 144 (100), 116 (33), 102 (2), 89 (14), 63 (4).
7-(N-(1’-Methoxycarbonylethyl)glyoxylamido)indole (3f) (isolated in a 2/8 mixture of 2f/3f). Rf (5 %
MeOH, 20 % EtOAc, 75 % hexane) 0.40; δH (500 MHz, CDCl3) 10.43 (1 H, brs, indole-NH), 8.78 (1 H, d, 7.8
Hz, Ar-H), 7.98 (1 H, d, 7.8 Hz, Ar-H), 7.72 (1 H, d, 6.1 Hz, NH), 7.34 (1 H, dd, 3.0 Hz, 2.3 Hz, indole-H),
7.21 (1 H, t, 7.8 Hz, Ar-H), 6.65 (1 H, dd, 3.0 Hz, 2.3 Hz, indole-H), 4.76 (1 H, qi, 7.3 Hz, N-CH) 3.83 (3 H,
s, O-CH3), 1.57 (3 H, d, 7.3 Hz, CHCH3). δC (125.7 MHz, CDCl3) 187.1, 167.4, 162.1, 135.9, 129.6, 129.4,
129.3, 125.1, 119.4, 116.6, 103.2, 52.7, 48.1, 18.2. IR (KBr, ν (cm-1)): 3402 (indole-NH), 3261 (NH), 1745
(COO), 1664 (CO), 1636 (CON); MS m/z (rel int.): 274 (31, M+), 215 (4), 144 (100), 116 (36), 102 (6), 89
(15), 63 (4).
7-(N-(1’-Methoxycarbonyl-2’-methylpropyl)carboxamido)indole (2g), Yield: 107 mg (39 %); pale
yellow viscous material; [Found: C, 65.46; H, 6.47; N, 10.05; C15H18N2O3 requires C, 65.68; H, 6.61; N, 10.21
%]; Rf (5 % MeOH, 15 % EtOAc, 80 % hexane) 0.64; δH (500 MHz, CDCl3) 10.28 (1 H, brs, indole-NH), 7.84
(1 H, d, 7.8 Hz, Ar-H), 7.51 (1 H, d, 7.8 Hz, Ar-H), 7.34 (1 H, dd, 3.0 Hz, 2.3 Hz, indole-H), 7.16 (1 H, t, 7.7
Hz, Ar-H), 6.91 (1 H, d, 8.3 Hz, NH), 6.59 (1 H, dd, 3.0 Hz, 2.3 Hz, indole-H), 4.84 (1 H, dd, 8.6 Hz, 5.1 Hz,
N-CH) 3.82 (3 H, s, O-CH3), 2.37-2.30 (1 H, m, CH(CH3)2), 1.06 (3 H, d, 6.9 Hz, CHCH3), 1.04 (3 H, d, 6.9
Hz, CHCH3). δC (125.7 MHz, CDCl3) 172.7, 167.7, 135.4, 129.6, 125.6, 125.1, 119.2, 118.7, 115.5, 102.0,
57.2, 52.3, 31.7, 19.1, 18.1. IR (KBr, ν (cm-1)): 3427 (NH), 1734 (COO), 1646 (CON); MS m/z (rel int.): 274
(29, M+), 215 (7), 171 (11), 160 (17), 144 (100), 130 (2), 116 (37), 89 (13), 63 (2).
7-(N-(1’-Methoxycarbonyl-2’-methylpropyl)glyoxylamido)indole (3g), Yield: 136 mg (45 %); yellow
solid material, mp. 71 ˚C; [Found: C, 63.46; H, 6.12; N, 9.03; C16H18N2O4 requires C, 63.56; H, 6.00; N, 9.27
%]; Rf (5 % MeOH, 15 % EtOAc, 80 % hexane) 0.52; δH (500 MHz, CDCl3) 10.46 (1 H, brs, indole-NH), 8.77
(1 H, d, 7.7 Hz, Ar-H), 7.98 (1 H, d, 7.7 Hz, Ar-H), 7.69 (1 H, d, 8.8 Hz, NH), 7.36 (1 H, dd, 3.0 Hz, 2.3 Hz,
indole-H), 7.21 (1 H, t, 7.7 Hz, Ar-H), 6.59 (1 H, dd, 3.0 Hz, 2.3 Hz, indole-H), 4.71 (1 H, dd, 9.1 Hz, 5.1 Hz,
N-CH) 3.82 (3 H, s, O-CH3), 2.39-2.30 (1 H, m, CH(CH3)2), 1.06 (3 H, d, 6.9 Hz, CHCH3), 1.03 (3 H, d, 6.9
Hz, CHCH3). δC (125.7 MHz, CDCl3)187.3 171.7, 162.4, 135.9, 129.6, 129.4, 129.3, 125.6, 119.4, 116.6,
15