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16
Apigeninidin Trimethylether Hexafluorophosphate (
10)
Purple powder; yield 93%; mp 201 °C. IR (KBr): 1652, 1640 (s, C=O), 1600, 1569, 1506, 1456, 1436, 1378, 1339, 1241, 1124, 1052, 834 (m, P-F) cm-1. UV/Vis [MeOH-HCl (5%, 1 N)]: λmax (ε) = 266 (24900), 394 (18000), 460 nm (13600 M-1·cm-1). 1H NMR [300 MHz, CD3CN-TFA-d
1 (1%)]: δ = 3.96 (3 H, s, OCH3), 4.07 (3 H, s, OCH3), 4.09 (3 H, s, OCH3), 6.80 (1 H, d, J = 2.2 Hz), 7.19 (2 H, m), 7.23 (1 H, dd, J = 2.2, 0.7 Hz), 8.05 (1 H, d, J = 8.5 Hz), 8.32 (2 H, m), 9.07 (1 H, dd, J = 8.5 Hz, 5
J = 0.7 Hz). 13C NMR [75 MHz, CD3CN-TFA-d
1 (1%)]: δ = 55.9/57.0/57.2 (OCH3), 93.4, 99.8, 111.3, 113.4, 115.8, 120.8, 131.9, 148.7, 158.8, 159.0, 167.0, 171.4, 171.7. MS (ESI, positive mode): 297 (100) [M+]. HRMS (ESI): m/z calcd: 297.1121; found: 297.1109.
17
Chrysinidin Hexafluorophosphate (
13)
Orange powder; yield 91%. IR (KBr): 3412 (s, br, OH), 1642 (s, C=O), 1580, 1563, 1541, 1381, 1340, 1269, 1239, 1203, 1193, 835 (m, P-F) cm-1. UV/Vis [MeOH-HCl (5%, 1 N)]: λmax (ε) = 274 (35400), 474 nm (36200 M-1·cm-1). 1H NMR [300 MHz, CD3CN-TFA-d
1 (1%)]: δ = 6.81 (1 H, d, J = 2.2 Hz), 7.11 (1 H, dd, J = 2.2, 0.7 Hz), 7.72 (2 H, m), 7.84 (1 H, m), 8.13 (1 H, d, J = 8.4 Hz), 8.35 (2 H, m), 9.25 (1 H, dd, J = 8.4, 0.7 Hz). 13C NMR [75 MHz, CD3CN-TFA-d
1 (1%)]: δ = 95.7, 102.9, 111.2, 114.4, 128.9, 129.1, 130.0, 135.8, 150.5, 158.4, 159.4, 171.1, 171.4. MS (ESI, positive mode): 239 (100) [M+]. HRMS (ESI): m/z calcd: 239.0703; found: 239.0696.
18 All synthesized compounds exhibit NMR spectroscopic data identical to previously reported ones in the literature.
[10-12]