Oroxylin A Chemical Properties

Melting point:

195-197℃

Boiling point:

346.76°C (rough estimate)

Density 

1.420

refractive index 

1.6200 (estimate)

storage temp. 

Sealed in dry,2-8°C

solubility 

DMF: 30 mg/ml; DMSO: 30 mg/ml; DMSO:PBS (pH 7.2) (1:4): 0.20 mg/ml

pka

6.48±0.40(Predicted)

form 

powder

color 

Yellow

InChI

InChI=1S/C16H12O5/c1-20-16-11(18)8-13-14(15(16)19)10(17)7-12(21-13)9-5-3-2-4-6-9/h2-8,18-19H,1H3

InChIKey

LKOJGSWUMISDOF-UHFFFAOYSA-N

SMILES

C1(C2=CC=CC=C2)OC2=CC(O)=C(OC)C(O)=C2C(=O)C=1

Safety Information

Hazard Codes 

Xn

Risk Statements 

22

Oroxylin A Usage And Synthesis

Chemical Properties

Yellow needle-shaped crystals, soluble in organic solvents such as methanol, ethanol, and DMSO, mainly derived from Scutellaria baicalensis and Melaleuca alternifolia.

Uses

food and beverages

Definition

ChEBI: A dihydroxy- and monomethoxy-flavone in which the hydroxy groups are positioned at C-5 and C-7 and the methoxy group is at C-6.

Biological Activity

Oroxylin A is a flavonoid isolated from Scutellaria baicalensis, which is one of the most important medicinal herbs in traditional Korean/Chinese/Japanese medicine. The amelioration of Abeta(25-35) peptide-induced memory impairment by oroxylin A is believed to be mediated via the GABAergic neurotransmitter system after a single administration, or by reductions in Abeta(25-35) peptide-induced astrocyte and microglia activations, iNOS expression, lipid peroxidation, and increased cholinergic neurotransmission after subchronic administration.

Synthesis

The general procedure for the synthesis of 5,7-dihydroxy-6-methoxy-2-phenyl-4H-benzopyran-4-one from 5,6,7-trimethoxy-2-phenyl-4H-benzopyran-4-one was as follows: 5,6,7-trimethoxy-2-phenyl-4H-benzopyran-4-one (0.20 g, 0.64 mmol) was dissolved in a mixture of 47% hydrobromic acid (5 mL) and glacial acetic acid (10 mL) in a mixed solution and the reaction was refluxed for 2 hours. Upon completion of the reaction, the reaction solution was quenched by carefully pouring it into crushed ice (200 g). The resulting yellow precipitate was collected by filtration and recrystallized from ethanol to afford 5,7-dihydroxy-6-methoxy-2-phenyl-4H-benzopyran-4-one (160 mg, 88% yield) with a melting point of 203-204 °C. The product structure was determined by 1H-NMR. The structure of the product was confirmed by 1H-NMR (DMSO-d6), IR, UV and MS analysis: 1H-NMR (DMSO-d6) δ: 3.91 (3H, s), 6.94 (1H, s), 6.98 (1H, s), 7.59 (3H, m), 8.10 (2H, d, J = 6.3 Hz), 8.77 (1H, s), 12.49 (1H, s); IR (KBr) cm-1: 3435, 1667; UV λmax (EtOH) nm (log ε): 322 (4.12), 278 (4.35), 216 (4.42); MS m/z: 285 (MH+).

References

[1] Chemical and pharmaceutical bulletin, 2003, vol. 51, # 3, p. 339 - 340
[2] Patent: US2004/242907, 2004, A1. Location in patent: Page 3
[3] Chemistry and Biodiversity, 2015, vol. 12, # 2, p. 259 - 272
[4] Bioorganic and Medicinal Chemistry Letters, 2012, vol. 22, # 7, p. 2534 - 2535

Oroxylin A(480-11-5)Related Product Information

• Oroxylin A-7-O-glucuronide
• Cepharanthine
• HINOKIFLAVONE
• HISPIDULIN
• SCUTELLAREIN TETRAMETHYL ETHER
• 3',5-DIHYDROXY-4',6,7-TRIMETHOXYFLAVONE
• CASTICIN
• 6,7-DIMETHOXY-3',4',5-TRIHYDROXYFLAVONE
• EUPATORIN-5-METHYL ETHER
• 3'-BENZYLOXY-4',5,6,7-TETRAMETHOXYFLAVONE
• 5,6,7-TRIMETHOXYFLAVONE
• 6-METHOXYLUTEOLIN
• 3',4',5',6,7,8-HEXAMETHOXY-5-HYDROXYFLAVONE
• 3',4',5',5,6,7-HEXAMETHOXYFLAVONE
• APIGENIN 6-GLUCOSYL-7-O-METHYL ETHER
• cirsimaritin
• Tangeretin
• SINENSETIN