| Identifier |
4 |
| NMR acquisition |
Bruker Avance III HD 600 MHz spectrometer; 5 mm helium-cooled inverse quadrupole resonance cryoprobe; 300 K; (CD₃)₂SO; solvent-signal internal references δH = 2.50 ppm and δC = 39.51 ppm |
| ¹H NMR (600 MHz, (CD₃)₂SO, 300 K; reported in main paper) |
δ = 8.34 (d, J = 1.5 Hz, 1H, CH-1), 8.06 (dd, J = 8.5, 1.5 Hz, 1H, CH-3), 7.92 (d, J = 8.5 Hz, 1H, CH-4), 7.98 (d, J = 8.5 Hz, 1H, CH-10), 8.27 (ss, J = 8.5, 1.7 Hz, 1H, CH-11), 8.50 (d, J = 1.7 Hz, 1H, CH-13), 7.64 (dd, J = 8.3, 1.6 Hz, 1H, CH-20), 6.99 (d, J = 8.3 Hz, 1H, CH-21), 7.77 (d, J = 1.6 Hz, 1H, CH-24) |
| ¹H NMR (600 MHz, (CD₃)₂SO, 300 K; reported in SI) |
δ = 8.34 (d, J = 1.5 Hz, 1H, CH-1), 8.06 (dd, J = 8.5, 1.5 Hz, 1H, CH-3), 7.92 (d, J = 8.5 Hz, 1H, CH-4), 7.98 (d, J = 8.5 Hz, 1H, CH-10), 8.27 (dd, J = 8.5, 1.7 Hz, 1H, CH-11), 8.50 (d, J = 1.7 Hz, 1H, CH-13), 7.64 (dd, J = 8.3, 1.6 Hz, 1H, CH-20), 6.99 (d, J = 8.3 Hz, 1H, CH-21), 7.77 (d, J = 1.6 Hz, 1H, CH-24) |
| ¹³C NMR (150 MHz, (CD₃)₂SO, 300 K) |
δ = 120.7 (C-1, CH), 128.0ᵃ (C-2, Cq), 127.0 (C-3, CH), 111.0 (C-4, CH), 153.2 (C-5, Cq), 141.7 (C-6, Cq), 142.6 (C-8, Cq), 152.6 (C-9, Cq), 111.8 (C-10, CH), 124.7 (C-11, CH), 122.8 (C-12, Cq), 118.3 (C-13, CH), 163.7 (C-14, Cq), 164.6 (C-18, Cq), 116.9 (C-19, Cq), 121.0ᵇ (C-20, CH), 115.3 (C-21, CH), 150.6 (C-22, Cq), 131.7ᵃ (C-23, Cq), 116.5ᵃ (C-24, CH), 166.9 (C-27, Cq); ᵃ chemical shift was derived from the HMBC spectrum; ᵇ chemical shift was derived from the HSQC spectrum |
| ¹H–¹H COSY correlations ((CD₃)₂SO, 300 K) |
1: (3); 3: (1), 4; 4: 3; 10: 11, (13); 11: 10; 13: (11); 20: 21, (24); 21: 20; 24: (20) |
| ¹H–¹³C HMBC correlations ((CD₃)₂SO, 300 K) |
1: 3, 5, 27; 3: 1, 4, 5, 27; 4: 2, 5, 6; 10: 8, 9, 12; 11: 9, 13, 14; 13: 9, 11, 14; 20: 22, 24; 21: 19, 23; 24: 18, 20, 22 |
| HRMS and LC–MS/MS acquisition |
Agilent 1200 HPLC system coupled to a Bruker compact QTOF mass spectrometer; flow injection with 100 % acetonitrile containing 0.1 % (v/v) formic acid at 300 µL min⁻¹ under isocratic conditions for 2 min; ESI positive-ion mode; 4.5 kV capillary voltage; N₂ drying gas at 9 L min⁻¹; m/z 50–1500; maximum resolution 23,000 |
| HRMS (ESI, positive-ion mode) |
m/z calcd for C₂₁H₁₃N₃O₅: 388.0928 [M+H]⁺; found: 388.0915 |
| LC–MS/MS (positive-ion mode, precursor m/z 388.09, 22 eV) |
Observed spectrum peak labels: m/z 226.0497, 254.0449, 343.0708, 371.0665, 388.0962 |