Antituberculosis: Synthesis and Antimycobacterial Activity of Novel Benzimidazole Derivatives

Table 2

¹H NMR results for compounds 1, 2, and 5a–g and selected ¹³C NMR results.

Compound	NMR (δ ppm)
Ethyl-4-fluoro-3-nitrobenzoate, 1	^1H NMR: 1.44 (3H, t, 𝐽= 7.2 Hz), 4.45 (2H, q, 𝐽= 7.2 Hz), 7.41 (1H, d, 𝐽= 8.4 Hz), 8.70 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.89 (1H, s)
Ethyl 3-amino-4-(4-(2-((4-(ethoxycarbonyl)-2-nitrophenyl)amino)ethyl)piperazin-1-yl)benzoate, 2	^1H NMR: 1.38 (3H, t, 𝐽= 7.2 Hz), 1.43 (3H, t, 𝐽= 7.2 Hz), 2.79 (4H, t, 𝐽= 4.8 Hz), 2.90 (2H, t, 𝐽= 6.9 Hz), 3.29 (4H, t, 𝐽= 4.8 Hz), 3.52 (2H, q, 𝐽= 7.2 Hz), 4.37 (2H, t, 𝐽= 6.9 Hz), 4.44 (2H, q, 𝐽= 7.2 Hz), 6.87 (1H, d, 𝐽= 8.4 Hz), 7.11 (1H, d, 𝐽= 8.4 Hz), 8.15 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.33 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.74 (1H, s), 8.84 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-phenyl-1H-benzo[d]imidazole-5-carboxylate, 5a	^1H NMR: 1.37 (3H, t, 𝐽= 7.2 Hz), 1.44 (3H, t, 𝐽= 7.2 Hz), 2.53 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.91 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 6.90–7.20 (5H, m), 7.50 (1H, d, 𝐽= 8.4 Hz), 8.11 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.57 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-chlorophenyl)-1H-benzo[d]imidazole-5-carboxylate, 5b	^1H NMR: 1.38 (3H, t, 𝐽= 7.2 Hz), 1.46 (3H, t, 𝐽= 7.2 Hz), 2.54 (4H, t, 𝐽= 4.8 Hz), 2.86 (2H, t, 𝐽= 6.9 Hz), 3.91 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 6.92 (1H, d, 𝐽= 8.4 Hz), 7.40 (1H, s), 7.47 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 7.52 (1H, d, 𝐽= 8.4 Hz), 7.65 (2H, d, 𝐽= 8.4 Hz), 7.85 (2H, d, 𝐽= 8.4 Hz), 8.12 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.58 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(2, 4-dihydroxyphenyl)-1H-benzo[d]imidazole-5-carboxylate, 5c	^1H NMR: 1.37 (3H, t, 𝐽= 7.2 Hz), 1.44 (3H, t, 𝐽= 7.2 Hz), 2.53 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.91 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.44 (2H, t, 𝐽= 6.9 Hz), 4.45 (2H, q, 𝐽= 7.2 Hz), 6.68 (1H, s), 6.87 (1H, dd, 𝐽1= 8.4 Hz, 𝐽2 = 1.5 Hz), 6.92 (1H, d, 𝐽= 8.4 Hz), 7.40 (1H, s), 7.44 (1H, d, 𝐽= 8.4 Hz), 7.50 (1H, d, 𝐽= 8.4 Hz), 7.56 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.16 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.56 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-(trifluoromethoxy)phenyl)-1H-benzo[d]imidazole-5-carboxylate, 5d	^1H NMR: 1.38 (3H, t, 𝐽= 7.2 Hz), 1.46 (3H, t, 𝐽= 7.2 Hz), 2.53 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.91 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 6.92 (1H, d, 𝐽= 8.4 Hz), 7.40 (1H, s), 7.47 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 7.52 (1H, d, 𝐽= 8.4 Hz), 7.66 (2H, d, 𝐽= 8.4 Hz), 7.84 (2H, d, 𝐽= 8.4 Hz), 8.12 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.59 (1H, s); ^13C NMR: 14.78, 43.48, 50.46, 54.47, 57.53, 61.08, 61.41, 110.28, 114.00, 116.46, 119.19, 120.97, 122.20, 125.92, 126.19, 126.23, 126.72, 134.17, 139.17, 141.08, 143.09, 143.32, 154.48, 160.05, 167.13, 167.36
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-p-tolyl-1H-benzo[d]imidazole-5-carboxylate, 5e	^1H NMR: 1.37 (3H, t, 𝐽= 7.2 Hz), 1.45 (3H, t, 𝐽= 7.2 Hz), 2.53 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.91 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 4.48 (3H, s), 6.90 (1H, d, 𝐽= 8.4 Hz), 7.40 (1H, s), 7.46 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 7.52 (1H, d, 𝐽= 8.4 Hz), 7.66 (2H, d, 𝐽= 8.4 Hz), 7.84 (2H, d, 𝐽= 8.4 Hz), 8.12 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.57 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(benzo[d][1, 3]dioxol-5-yl)-1H-benzo[d]imidazole-5-carboxylate, 5f	^1H NMR: 1.38 (3H, t, 𝐽= 7.2 Hz), 1.46 (3H, t, 𝐽= 7.2 Hz), 2.53 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.90 (4H, t, 𝐽= 4.8 Hz), 4.35 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 6.10 (2H, s), 6.92 (1H, d, 𝐽= 8.4 Hz), 7.40 (1H, s), 7.47 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 7.35 (1H, d, 𝐽= 8.4 Hz), 7.45–7.55 (3H, m), 8.08 (1H, dd, 𝐽1 = 8.4 Hz, 𝐽2 = 1.5 Hz), 8.55 (1H, s)
Ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1-yl)ethyl)-2-(4-(5-(4-fluorophenyl)pyridin-3-yl)phenyl)-1H-benzo[d]imidazole-5-carboxylate, 5g	^1H NMR: 1.39 (3H, t, 𝐽= 7.2 Hz), 1.47 (3H, t, 𝐽= 7.2 Hz), 2.54 (4H, t, 𝐽= 4.8 Hz), 2.85 (2H, t, 𝐽= 6.9 Hz), 3.93 (4H, t, 𝐽= 4.8 Hz), 4.32 (2H, q, 𝐽= 7.2 Hz), 4.45 (2H, t, 𝐽= 6.9 Hz), 4.46 (2H, q, 𝐽= 7.2 Hz), 6.90–8.20 (10H, m), 8.59 (1H, s), 8.70 (2H, s)