520-36-5

Usage

Uses

Used in Alzheimer's Treatment/Prevention:
Apigenin is used as an active antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognitive enhancing substance for the treatment and prevention of Alzheimer's disease.
Used in Antimicrobial Applications:
Apigenin is used as an antibacterial, antiviral, antifungal, and antiparasitic agent. It can be combined with other antibiotics to enhance their effects and increase their efficacy against various types of bacteria.
Used in Cancer Therapy:
Apigenin is used as a promising reagent for cancer therapy. It has the potential to be developed as a dietary supplement or as an adjuvant chemotherapeutic agent, contributing to the fight against cancer.
Used in the Food Industry:
Apigenin is used as a natural compound in the food industry, where it is found in significant amounts in vegetables (parsley, celery, onions), fruits (oranges), herbs (chamomile, thyme, oregano, basil), and plant-based beverages (tea, beer, and wine). It adds to the nutritional value and health benefits of these products.
Used in Pharmaceutical Applications:
Apigenin is used in the pharmaceutical industry for its potential therapeutic applications, including the development of new drugs and supplements for various health conditions, such as Alzheimer's disease and cancer.

Preparation

4-hydroxybenzaldehyde (1.22 g, 9.97 mmol, 1.0 equiv) was added to asolution of 50% KOH (aq.) (6.72 g, 59.82 mmol, 6.0 equiv) and ethanol (3 mL) andstirred for 10 min. Then compound 9 (2.02g, 9.97 mmol, 1.0 equiv) was added to the reaction mixture and heated to 60 °C and stirred for 4 h. After cooled toroom temperature, the mixture was poured into ice water and acidified withconcentrated hydrochloric acid to pH = 3. Then the suspension was filtrated, washed and the residue was dried toafford Apigenin(2.43 g, 90%) as a red solid.

Anticancer Research

It induces apoptosis by targeting leptin/leptin receptor pathway and by targeting caspase-dependent extrinsic pathway aswell as STAT3 signaling pathway in lung adenocarcinoma and BT-474 breast cancercells, respectively. It shows antitumor activity against breastcancer MCF-7 cells and colon cancer HCT 116 cells and is a mediator of cancerchemoprevention and an inducer of autophagy. It can be used to treat colon canceras it induces apoptosis in colon cancer cells. It also increase melanogenesis in B16cells by activating the p38 MAPK pathway.

Purification Methods

The current method for the purification of apigenin is crude-solvent extraction method by using solvent in small quantity and also time saving. Apigenin that was isolated from Symphyotrichum novae-angliae was obtained in large quantity and directly from extract.

InChI:InChI=1/C15H10O5/c16-9-3-1-8(2-4-9)13-7-12(19)15-11(18)5-10(17)6-14(15)20-13/h1-7,16-18H

Synthetic route

2,4’,5,7-tetrahydroxyflavanone → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride In methanol; water	100%

5,7-Dihydroxy-2-(4-hydroxy-phenyl)-chroman-4-on (480-41-1) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With sulfuric acid; iodine In dimethyl sulfoxide at 100℃; for 1.5h;	95%
With pyridine; iodine for 4h; Heating;	93%
With pyridine; iodine at 95℃; for 5h;	66%

apigenin 7-O-glucoside (578-74-5) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride for 2h; Heating;	95%
Acid hydrolysis;
Acidic conditions;

2-chloro-1-(2,4,6-trihydroxyphenyl)ethan-1-one (110865-03-7) + 4-hydroxy-benzaldehyde (123-08-0) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
Stage #1: 2-chloro-1-(2,4,6-trihydroxyphenyl)ethan-1-one; 4-hydroxy-benzaldehyde With sodium hydroxide In ethanol; water Stage #2: With hydrogenchloride Further stages.;	92%
Stage #1: 4-hydroxy-benzaldehyde With potassium hydroxide In ethanol; water for 0.166667h; Inert atmosphere; Stage #2: 2-chloro-1-(2,4,6-trihydroxyphenyl)ethan-1-one In ethanol; water at 60℃; for 4h;	90%
With potassium hydroxide In ethanol at 20 - 60℃; for 6h;	83%

4',5,7-trimethoxyflavone (5631-70-9) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With pyridine hydrochloride at 180 - 190℃; for 6h; Inert atmosphere;	90%
With pyridine hydrochloride at 180℃; for 6h; Inert atmosphere;	90%
With boron tribromide In dichloromethane at 20℃; for 24h; Inert atmosphere;	90%
Stage #1: 4',5,7-trimethoxyflavone With aluminum (III) chloride In toluene at 80 - 140℃; Stage #2: With hydrogenchloride In water; toluene at 0℃; Reagent/catalyst; Solvent; Temperature; Time;	61.5%
With hydrogen iodide In acetic anhydride at 115 - 118℃; for 6h;	10 g

naringenin (480-41-1) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With iodine In pyridine at 90℃; for 8h;	86%
With flavone synthase I Product distribution;
With GLUTATHIONE; N-[tris(hydroxymethyl)methyl]glycine; flavone synthase II; NADPH; potassium hydroxide at 25℃; for 0.5h; pH=7.9; Enzymatic reaction;
With 2,3-dicyano-5,6-dichloro-p-benzoquinone

2',4',6',4-tetrahydroxydihydrochalcone (25515-46-2, 73692-50-9) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With oxygen at 20℃; under 760.051 Torr; for 0.866667h; Reagent/catalyst;	77%

1-[4-(tert-Butyl-dimethyl-silanyloxy)-phenyl]-3-(2,4,6-trihydroxy-phenyl)-propane-1,3-dione → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With sulfuric acid In acetic acid at 95 - 100℃; for 1h;	76%

apigenin-7-O-β-D-glucuronide (29741-09-1, 56317-11-4) → D-glucuronic acid (6556-12-3, 489-91-8, 528-16-5, 552-12-5, 577-46-8, 643-33-4, 2240-07-5, 6294-16-2, 10133-02-5, 18402-78-3, 18968-14-4, 21179-08-8, 23018-83-9, 33599-45-0, 33599-46-1, 46171-67-9, 46171-69-1, 46172-26-3, 70021-34-0, 71031-08-8, 104195-06-4, 106499-29-0, 124817-72-7) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With sulfuric acid for 5h;	A n/a B 68%
With sulfuric acid for 5h;

3,5-dihydroxyphenol (108-73-6) + ethyl (4-hydroxybenzoyl)acetate (77103-47-0) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
for 0.0633333h; microwave irradiation;	66%

C27H18O9S2 → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With potassium carbonate In methanol at 65℃; for 5h; Inert atmosphere;	66%

7-benzyloxy-5-hydroxy-2-(4-hydroxyphenyl)chroman-4-one (874202-29-6) → 7-O-benzylapigenin (20450-81-1) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
Stage #1: 7-benzyloxy-5-hydroxy-2-(4-hydroxyphenyl)chroman-4-one With pyridine; iodine for 4h; Heating / reflux; Stage #2: With hydrogenchloride In water	A 58% B 24%

4,6-bis(methoxymethyl)-2-(4-acetoxybenzoyloxy)acetophenone → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
Stage #1: 4,6-bis(methoxymethyl)-2-(4-acetoxybenzoyloxy)acetophenone With potassium hydroxide In pyridine at 50℃; for 0.333333h; Stage #2: With acetic acid In pyridine; water for 0.5h; Stage #3: With hydrogenchloride In methanol Reflux;	58%

4',5,7-trimethoxyflavone (5631-70-9) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + 5,7-dihydroxy-2-(4'-methoxyphenyl)-4H-1-benzopyran-4-one (480-44-4)

Conditions	Yield
With N-butyl-N-methylimidazolium heptachlorodialuminate In dichloromethane at 40℃; for 4h;	A 54% B 16%

apigenin 7-O-[β-D-glucuronopyranosyl-(1->2)]-O-β-D-glucuronopyranoside → D-Glucuronic acid (6556-12-3) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
Acid hydrolysis;	A n/a B 52%

5,7-dihydroxy-2-phenyl-chromen-4-one (480-40-0) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + 2-(3,4-Dihydroxy-phenyl)-5,7-dihydroxy-chromen-4-on (491-70-3) + luteolin 3'-monosulphate

Conditions	Yield
With Mucore ramannianus (ATCC 9628) In N,N-dimethyl-formamide for 336h; Microbiological reaction;	A 3% B 10.2% C 10.2%

5,7-Dihydroxy-2-(4-hydroxy-phenyl)-chroman-4-on (480-41-1) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + eriodictyol (4049-38-1)

Conditions	Yield
With plasmid pFusionF87V-carrying recombinant Escherichia coli BL21 (DE3) cells at 28℃; for 24h; Microbiological reaction;	A 3.7% B 5.2%

5,7-dihydroxy-2-phenyl-chromen-4-one (480-40-0) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With Aspergillus alliaceous (ATCC 10060) In N,N-dimethyl-formamide for 336h; Microbiological reaction;	4.1%

6-bromo-5-hydroxy-7,4'-dimethoxyflavone (35095-48-8) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogen iodide; acetic anhydride

dihydrokaempferol (724434-08-6) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With sulfuric acid

4'-O-methylapigenin 6-C-β-D-glucopyranoside (21089-34-9) → D-Glucose (2280-44-6) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride; water In acetic acid at 100℃; for 24h;
With iron(III) chloride at 100℃; for 6h;

FLAVONE (525-82-6) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With pyridine hydrochloride

5-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (5128-44-9) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With pyridine hydrochloride at 170℃; for 2h; Product distribution; for identification of structure;

apigenin 7-p-coumarate (126661-94-7) → p-Coumaric Acid (7400-08-0) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With sodium hydroxide for 0.5h; Ambient temperature;

crotonoylcosmosiin (123656-62-2) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride In methanol for 5h; Heating;	6 mg

apigenin 7-(4-O-β-glucosyl-trans-p-coumarate) (126871-97-4) → D-Glucose (2280-44-6) + p-Coumaric Acid (7400-08-0) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride Heating;
With hydrogenchloride Heating;

2-hydroxynaringenin (64325-11-7) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With hydrogenchloride In acetic acid for 1h; Heating; Yield given;
With hydrogenchloride; acetic acid at 100℃; for 1.5h; Yield given;

nivyaside (84563-91-7) → D-Glucose (2280-44-6) + cyclohexanetetrol-(1r,2t,3t,4c) (20089-18-3, 907575-48-8) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
With Kiliani's mixture for 6h; Heating;	A n/a B n/a C 36 mg

apigenin 5-O-α-L-rhamnopyranosyl-(1'''->2'')-6''-O-acetyl-β-D-glucopyranoside (125300-52-9) → 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5)

Conditions	Yield
sulfuric acid In ethanol; water for 6h; Heating;

chlorosulfuric acid 2,2,2-trichloroethyl ester (764-09-0) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → C21H13Cl9O14S3

Conditions	Yield
With dmap; triethylamine In tetrahydrofuran at 20℃;	95%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 2-(3,4-Dihydroxy-phenyl)-5,7-dihydroxy-chromen-4-on (491-70-3)

Conditions	Yield
With C9H8IO4Pol In dimethyl sulfoxide at 25℃; for 2h;	95%
With cytochromes P450 in human liver microsomes Kinetics; Enzymatic reaction;

2-iodo-propane (75-30-9) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 5-hydroxy-7-isopropoxy-2-(4-isopropoxyphenyl)-4H-chromen-4-one

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 30h; Inert atmosphere;	95%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → C15H8F2O9S2

Conditions	Yield
With fluorosulfonyl fluoride In acetonitrile at 20℃; for 3h; Sealed tube;	95%

diazomethane (186581-53-3, 908094-01-9) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 5-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (5128-44-9)

Conditions	Yield
In methanol; diethyl ether at 20℃; for 0.5h;	94%
With ethanol
In methanol at 20℃; for 1h;

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + acetic anhydride (108-24-7) → apigenin triacetate (3316-46-9)

Conditions	Yield
With pyridine at 70℃; for 6h;	94%
With pyridine at 140℃; for 8h; Temperature;	90.8%
With pyridine Reflux;	87.2%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + chloroacetic acid ethyl ester (105-39-5) → diethyl 2,2'-((2-(4-(2-ethoxy-2-oxoethoxy)phenyl)-4-oxo-4H-chromene-5,7-diyl)bis(oxy))diacetate

Conditions	Yield
Stage #1: 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 0.75h; Stage #2: chloroacetic acid ethyl ester In N,N-dimethyl-formamide at 20℃; for 24h;	94%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 6,8-dibromo-5,7,4'-trihydroxyflavone (1006032-73-0)

Conditions	Yield
With N-Bromosuccinimide In trifluoroacetic acid at 20℃; for 5h;	93%
With N-Bromosuccinimide In acetone at 22℃; for 0.716667h;

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 5,7-Dihydroxy-2-(4-hydroxy-phenyl)-chroman-4-on (480-41-1)

Conditions	Yield
With palladium 10% on activated carbon; hydrogen at 20℃;	91%
With palladium 10% on activated carbon; hydrogen	25%

europium(III) oxide + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + water (7732-18-5) → C45H27EuO15*2H2O

Conditions	Yield
With dihydrogen peroxide; nitric acid; triethylamine In ethanol at 20℃; for 20h; pH=8; Reagent/catalyst; Darkness;	90.93%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + benzoyl chloride (98-88-4) → 5,7,4'-tribenzoyloxyflavone

Conditions	Yield
With pyridine hydrochloride at 140 - 200℃; for 9h;	89%
With potassium hydroxide

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + tert-butyldimethylsilyl chloride (18162-48-6) → 7,4'-di-O-(tert-butyldimethylsilyl)apigenin

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene In dichloromethane at 20℃; for 5h;	89%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + Hexanoyl chloride (142-61-0) → 5,7,4'-tri-O-hexanoyl apigenin (1145669-46-0)

Conditions	Yield
With dmap; triethylamine In N,N-dimethyl-formamide for 8h; Cooling with ice;	88%
With dmap; triethylamine In N,N-dimethyl-formamide at 20℃; for 4.5h; Cooling with ice;	87%
With dmap; triethylamine In N,N-dimethyl-formamide

methyl 6-bromohexanoate (14273-90-6) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → methyl 6-((5-hydroxy-2-(4-hydroxyphenyl)-4-oxo-4H-chromen-7-yl)oxy)hexanoate

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 70℃; for 6h; Inert atmosphere;	87%
With potassium carbonate In N,N-dimethyl-formamide at 80℃; for 6h;	20%

4-chloro-3,5-dinitrobenzotrifluoride (393-75-9) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 7-(2,6-dinitro-4-(trifluoromethyl)phenoxy)-5-hydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one

Conditions	Yield
With potassium tert-butylate In N,N-dimethyl-formamide at 20℃;	84%

formaldehyd (50-00-0) + furan-2-ylmethanamine (617-89-0) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → C36H31N3O8

Conditions	Yield
In dimethyl sulfoxide at 100℃; for 12h;	84%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 5,7-dihydroxy-2-(4-hydroxyphenyl-3,5-D2)-4H-1-benzopyran-4-one-3,6,8-D3 (263711-74-6)

Conditions	Yield
With boron trifluoride; [D3]phosphoric acid In water-d2 at 55℃; for 96h; deuteration;	83%
Multi-step reaction with 3 steps 1: D2O / acetone 2: 1-butyl-3-methylimidazolium chloride; DCl; D2O / 0.33 h / 120 °C / 3750.38 Torr / microwave irradiation 3: H2O View Scheme

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + diethyl chlorophosphate (814-49-3) → C27H37O14P3

Conditions	Yield
With dmap; triethylamine In tetrahydrofuran at 20℃; for 24.5h; Inert atmosphere; Cooling with ice;	83%
With dmap; triethylamine In tetrahydrofuran at 70℃; for 3.5h; Cooling with ice; Inert atmosphere;

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + acetic anhydride (108-24-7) → 7,4'-diacetoxy-5-hydroxyflavone (857-79-4)

Conditions	Yield
	82%
With pyridine
With pyridine at 20℃; for 24h;

2-iodo-propane (75-30-9) + 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → 5,7-diisopropoxy-2-(4-isopropoxyphenyl)-4H-benzopyran-4-one

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide for 24h; Inert atmosphere;	82%
With potassium carbonate In N,N-dimethyl-formamide at 60℃; for 24h; Inert atmosphere;	78%
With potassium carbonate In N,N-dimethyl-formamide	73%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) → C15H9O8S(1-)*K(1+) (120562-19-8) + C15H8O11S2(2-)*2K(1+) (116097-08-6)

Conditions	Yield
With potassium acetate; tetra(n-butyl)ammonium hydrogensulfate; dicyclohexyl-carbodiimide In pyridine at 4℃; for 72h; Yields of byproduct given;	A n/a B 81%
With potassium acetate; tetra(n-butyl)ammonium hydrogensulfate; dicyclohexyl-carbodiimide In pyridine at 4℃; for 72h; Yields of byproduct given;	A 28% B n/a

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + diazomethyl-trimethyl-silane (18107-18-1) → 5-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (5128-44-9)

Conditions	Yield
In methanol; hexane; dichloromethane at 20℃; for 12h;	81%

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + dimethyl sulfate (77-78-1) → 5-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (5128-44-9)

Conditions	Yield
With potassium hydroxide In water; acetone at 20℃; for 4h;	80%
With potassium hydroxide
With sodium hydroxide
With potassium carbonate regioselective reaction;
With potassium carbonate In acetone at 65℃;

5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (520-36-5) + methyl iodide (74-88-4) → 5,7-dihydroxy-2-(4'-methoxyphenyl)-4H-1-benzopyran-4-one (480-44-4)

Conditions	Yield
With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 18h; Inert atmosphere; regiospecific reaction;	79%
With potassium carbonate In N,N-dimethyl-formamide for 2h;

Upstream product

• 480-41-1 5,7-Dihydroxy-2-(4-hydroxy-phenyl)-chroman-4-on 
• 724434-08-6 dihydrokaempferol 
• 21089-34-9 4'-O-methylapigenin 6-C-β-D-glucopyranoside 
• 29741-09-1 apigenin-7-O-β-D-glucuronide 
• 525-82-6 FLAVONE 
• 126661-94-7 apigenin 7-p-coumarate 
• 123656-62-2 crotonoylcosmosiin 
• 126871-97-4 apigenin 7-(4-O-β-glucosyl-trans-p-coumarate) 
• 578-74-5 apigenin 7-O-glucoside 
• 28757-27-9 Apigenin 5-O-β-D-glucopyranoside 
• 29741-09-1 apigenin-7-glucuronic acid 
• 26544-34-3 apiin 
• 480-41-1 naringenin 
• 480-41-1 (+)-Naringenin 

Downstream Products

• 578-74-5 apigenin 7-O-glucoside 
• 68097-12-1 7-O-prenylapigenin 
• 68097-13-2 6-prenylapigenin 
• 70872-32-1 6,8-di-C-prenylapigenin 
• 76288-44-3 5-Hydroxy-2-(4-hydroxy-phenyl)-8,8-dimethyl-7,8-dihydro-6H-pyrano[3,2-g]chromen-4-one 
• 76288-54-5 4',7-di-O-prenylapigenin 
• 76288-50-1 4',5-dihydroxy-8-C-prenyl-6'',6''-dimethyl-4'',5''-dihydropyrano<2'',3'':7,6>flavone 
• 76288-53-4 4'-(dimethylallyl)apigenin 
• 76288-42-1 4',5-dihydroxy-6'',6''-dimethyl-5''-C-prenyl-4'',5''-dihydropyrano<2'',3'':7,6>flavone 
• 76288-49-8 4',5-dihydroxy-6'',6''-dimethyl-5''-C-prenyl-4'',5''-dihydropyrano<2'',3'':7,8>flavone 
• 76288-47-6 6′′,6′′-dimethyl-4′′,5′′-dihydropyrano[2′′,3′′:7,6]apigenin 
• 132351-62-3 5,7-diacetoxy-4'-hydroxyflavone 
• 130999-29-0 Apigen-4'7-diyl-di(2,3,4,6-tetra-O-acetyl-β-D-glucopranoside) 
• 130999-30-3 apigen-4'7-diyl-di(2,3,4,6-tetra-O-acetyl-β-D-galactopyranoside) 

Relevant academic research and scientific papers

Biotransformation of chrysin and apigenin by Cunninghamella elegans

Biotransformation of chrysin by Cunninghamella elegans NRRL 1392 produced apigenin, apigenin 7-sulfate, apigenin 7,4′-disulfate, and a new metabolite identified as chrysin 7-sulfate. On the other hand, fermentation of apigenin, using the same microorganism, yielded apigenin 7-sulfate and apigenin 7,4′-disulfate. The structures of the metabolites were established by spectral analysis, and acid and enzyme hydrolyses in addition to comparison with reference samples.

Regioselective ortho-Hydroxylations of Flavonoids by Yeast

Natural flavonoids, such as naringenin, hesperetin, chrysin, apigenin, luteolin, quercetin, epicatechin, and biochanin A, were subjected to microbiological transformations by Rhodotorula glutinis. Yeast was able to regioselectively C-8 hydroxylate hesperetin, luteolin, and chrysin. Naringenin was transformed to 8- and 6-hydroxyderivatives. Quercetin, epicatechin, and biochanin A did not undergo biotransformation. A metabolic pathway for the degradation of chrysin has been elucidated. The metabolism of chrysin proceeds via an initial C-8 hydroxylation to norwogonin, followed by A-ring cleavage to 4-hydroxy-6-phenyl-2H-pyran-2-one.

New Flavonoid Glycoside from Thalictrum minus

The new flavonoid diglycoside thamiflaside was isolated from the aerial part of Thalictrum minus. The chemical structure of this glycoside was determined as apigenin 7-O-α-L-2″′-methoxyrhamnopyranosyl-(1→6)-β-D-glucopyranoside based on PMR and 13/su

A new flavonoid glycoside from the leaf of Cephalotaxus koreana

A new flavone glycoside, apigenin 5-O-α-l-rhamnopyranosyl-(1 → 3)-β-d-glucopyranoside (1), along with four known flavonol glycosides (2-5), were isolated from the leaf of Cephalotaxus koreana. The new glycoside 1 showed inhibitory activity in superoxide radical scavenging assay with IC50 value of 13.0 μM, while it showed weak activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. Compounds 2-5 exhibited antioxidant activity in scavenging DPPH and superoxide radicals with IC50 values ranging from 5.7 to 22.3 μM.

Cloning of parsley flavone synthase I

A cDNA encoding flavone synthase I was amplified by RT-PCR from leaflets of Petroselinum crispum cv. Italian Giant seedlings and functionally expressed in yeast cells. The identity of the recombinant, 2-oxoglutarate-dependent enzyme was verified in assays converting (2S)-naringenin to apigenin.

FLAVONOID GLYCOSIDES OF ARTEMISIA MONOSPERMA AND A. HERBA-ALBA

Ten flavonoid glycosides were isolated and identified from Artemisia monosperma: vicenin-2, lucenin-2, acacetin 7-glucoside, acacetin 7-rutinoside, the 3-glucosides and 3-rutinosides of quercetin and patuletin, and the 5-glucosides of quercetin and isorhamnetin.From Artemisia herba-alba eight flavonoid glycosides were isolated and identified: isovitexin, vicenin-2, schaftoside, isoschaftoside and the 3-glucosides and 3-rutinosides of quercetin and patuletin.Key Word Index - Artemisia monosperma; A herba-alba; Compositae; flavone and flavonol glycosides.

A NEW GLYCOSYLATED FLAVONOID, 7-O-α-L-RHAMNOPYRANOSYL-4'-O-RUTINOSYLAPIGENIN, IN THE EXUDATE FROM GERMINATING SEEDS OF Sesbania rostrata

The title apigenin triglycoside was isolated (4 mg/6000 seeds) by reversephase column chromatography as the major u.v.-absorbing compound in the exudate of germinating seeds of Sesbania rostrata.The structure was assigned on the basis of u.v. spectra, f.a.b.-mass-spectral and 2D-n.m.r. data.The triglycoside was released continuously from the germinating seeds, but at a decreasing rate during the first two weeks.

COSMETIC COMPOSITION FOR SKIN IMPROVEMENT COMPRISING GREEN BARLEY EXTRACT

Provided is a cosmetic composition for skin improvement including a green barley extract.

Discovery of Novel Apigenin-Piperazine Hybrids as Potent and Selective Poly (ADP-Ribose) Polymerase-1 (PARP-1) Inhibitors for the Treatment of Cancer

Poly (ADP-ribose) polymerase-1 (PARP-1) is a potential target for the discovery of chemosensitizers and anticancer drugs. Amentoflavone (AMF) is reported to be a selective PARP-1 inhibitor. Here, structural modifications and trimming of AMF have led to a series of AMF derivatives (9a-h) and apigenin-piperazine/piperidine hybrids (14a-p, 15a-p, 17a-h, and 19a-f), respectively. Among these compounds, 15l exhibited a potent PARP-1 inhibitory effect (IC50 = 14.7 nM) and possessed high selectivity to PARP-1 over PARP-2 (61.2-fold). Molecular dynamics simulation and the cellular thermal shift assay revealed that 15l directly bound to the PARP-1 structure. In in vitro and in vivo studies, 15l showed a potent chemotherapy sensitizing effect against A549 cells and a selective cytotoxic effect toward SK-OV-3 cells through PARP-1 inhibition. 15l·2HCl also displayed good ADME characteristics, pharmacokinetic parameters, and a desirable safety margin. These findings demonstrated that 15l·2HCl may serve as a lead compound for chemosensitizers and the (BRCA-1)-deficient cancer therapy.

Continuous flow microchannel synthesis process of flavonoid compounds

The invention provides a continuous flow microchannel synthesis process of flavonoid compounds. According to the process, hesperidin and iodine elementary substance are used as raw materials and react in a continuous flow microchannel reactor in the presence of a reaction solvent to synthesize the flavonoid compound as shown in a formula A. Compared with a traditional kettle-type preparation process, the process disclosed by the invention has the advantages that the preparation time is obviously shortened, and the conversion rate of raw materials and the yield of products are obviously improved; and especially, when the diosmin is prepared under optimal process conditions of continuous flow microchannel synthesis, the conversion rate of the raw material hesperidin is as high as 96.48%, and the yield of the product diosmin is as high as 81.96%. The continuous flow micro-channel synthesis process provided by the invention is beneficial to realizing safe, efficient and rapid industrial production of flavonoid compounds, and has a wide application prospect.