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ChemicalBook CAS DataBase List Tangeretin
481-53-8

Tangeretin synthesis

9synthesis methods
-

Yield:481-53-8 86%

Reaction Conditions:

with potassium carbonate in acetone at 65; for 5 h;

Steps:

Synthesis of 5,6,7,8,4′-pentamethoxyflavone (tangeretin)(5)

Me2SO4 (0.1 mL, 3 equiv.) was added dropwise to stirredsolution of 3 (135 mg) in acetone and K2CO3 (0.91 g, 6.48mmol) at 65 °C. The reaction was terminated after 5 h, andthe mixture was filtered. The solution was evaporated toafford a solid residue. The crude solid was chromatographedon silica gel using petroleum ether/ethyl acetate (v/v, 3:1) as eluent to afford light yellow crystals of 5 (115 mg,yield: 86%), m.p. 151-153 °C (lit[12]. 152-153 °C); 1HNMR (CDCl3): δ 7.80 (d, J = 8.8 Hz, 2H, H-2′ and 6′), 6.94(d, J = 8.8 Hz, 2H, H-3′ and 5′), 6.52 (s, 1H, H-3), 4.03,3.94, 3.87, 3.81, (each, s, each 3H, -OCH3); 13C NMR(CDCl3): δ 176.3, 161.3, 160.1, 150.3, 147.3, 146.7, 143.0,137.1, 126.7, 122.8, 113.8, 113.5, 105.6, 61.2, 61.0, 60.8,60.6, 54.5; IR (KBr): ν 2946, 2843, 1650, 1607, 1587,1512, 1462, 1363, 1265, 1181, 1074, 968, 830 cm-1; MS(m/z, EI): 372 (M+), 327, 315, 287, 259, 194, 135, 77, 57;HRMS (EI): m/z [M]+ calcd for C20H20O7: 372.1209,found: 372.1204.

References:

Nguyen, Van-Son;Li, Wei;Li, Yue;Wang, Qiuan [Medicinal Chemistry Research,2017,vol. 26,# 7,p. 1585 - 1592]

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