7555-80-8

Upstream product

• 480-16-0 morin 
• 77-78-1 dimethyl sulfate 
• 84757-50-6 2-(2,4-dimethoxyphenyl)-3-hydroxy-5,7-dimethoxy-4H-chromen-4-one 
• 74-88-4 methyl iodide 
• 186581-53-3 diazomethane 
• 613-45-6 2,4-Dimethoxybenzaldehyde 
• 64200-22-2 (E)-1-(2′-hydroxy-4′,6′-dimethoxyphenyl)-3-(2,4-dimethoxyphenyl)prop-2-en-1-one 
• 90-24-4 2-hydroxy-4,6-dimethoxyacetophenone 

Downstream Products

• 19056-75-8 2-(2,4-dimethoxyphenyl)-5-hydroxy-3,7-dimethoxy-4H-chromen-4-one 
• 91-52-1 2,4 dimethoxybenzoic acid 
• 84757-51-7 2-(2,4-Dimethoxy-phenyl)-5,8-dihydroxy-3,7-dimethoxy-chromen-4-one 
• 71787-04-7 5-hydroxy-3,7,8,2',4'-pentamethoxyflavone 

Relevant academic research and scientific papers

Pharmacokinetics and Metabolites of 12 Bioactive Polymethoxyflavones in Rat Plasma

Polymethoxyflavones (PMFs) are a subgroup of flavonoids possessing various health benefits. 3,5,7,4′-Tetramethoxyflavone (1), 5,6,7,4′-tetramethylflavone (2), 3,7,3′,4′-tetramethoxyflavone (3), 5,7,3′,4′-tetramethoxyflavone (4), 5-hydroxy-3,7,2′,4′-tetramethoxyflavone (5), 3,5,7,2′,4′-pentamethoxyflavone (6), 5-hydroxy-3,7,3′,4′-tetramethoxyflavone (7), 3-hydroxy-5,7,3′,4′-tetramethylflavone (8), 3,5,7,3′,4′-pentamethoxyflavone (9), 5-hydroxy-3,7,3′,4′,5′-pentamethoxyflavone (10), 3-hydroxy-5,7,3′,4′,5′-pentamethoxyflavone (11), and 3,5,7,3′,4′,5′-hexamethoxylflavone (12) were 12 bioactive and available PMFs. The aim of this study was to investigate the pharmacokinetic, metabolite, and antitumor activities as well as the structure-pharmacokinetic-antitumor activity relationships of these 12 PMFs to facilitate further studies of their medicinal potentials. The cytotoxicity of PMFs with a hydroxy group toward HeLa, A549, HepG2, and HCT116 cancer cell lines was generally significantly more potent than that of PMFs without a hydroxy group. Compounds 5, 7, 8, 10, and 11 were all undetectable in rat plasma, while compounds 1-4, 6, 9, and 12 were detectable. Both the number and position of hydroxy and methoxy groups played an important role in modulating PMF pharmacokinetics and metabolites.

Synthesis and biological evaluation of flavones and benzoflavones as inhibitors of BCRP/ABCG2

Multidrug resistance (MDR) often leads to a failure of cancer chemotherapy. Breast Cancer Resistance Protein (BCRP/ABCG2), a member of the superfamily of ATP binding cassette proteins has been found to confer MDR in cancer cells by transporting molecules with amphiphilic character out of the cells using energy from ATP hydrolysis. Inhibiting BCRP can be a solution to overcome MDR.We synthesized a series of flavones, 7,8-benzofl avones and 5,6-benzo flavones with varying substituents at positions 3, 3′ and 4′ of the (benzo)fl avone structure. All synthesized compounds were tested for BCRP inhibition in Hoechst 33342 and pheophorbide A accumulation assays using MDCK cells expressing BCRP. All the compounds were further screened for their P-glycoprotein (P-gp) and Multidrug resistance-associated protein 1 (MRP1) inhibitory activity by calcein AM accumulation assay to check the selectivity towards BCRP. In addition most active compounds were investigated for their cytotoxicity. It was observed that in most cases 7,8-benzoflavones are more potent in comparison to the 5,6-benzoflavones. In general it was found that presence of a 3-OCH3 substituent leads to increase in activity in comparison to presence of OH or no substitution at position 3. Also, it was found that presence of 3′,4′-OCH3 on phenyl ring lead to increase in activity as compared to other substituents. Compound 24, a 7,8-benzoflavone derivative was found to be most potent being 50 times selective for BCRP and showing very low cytotoxicity at higher concentrations.

Synthesis and biological activities of flavonoid derivatives as A3 adenosine receptor antagonists

A broad screening of phytochemicals has demonstrated that certain flavone and flavonol derivatives have a relatively high affinity at A3 adenosine receptors, with K(i) values of ≥1 μM (Ji et al. J. Med. Chem. 1996, 39, 781-788). We have further modified the flavone structure to achieve a degree of selectivity for cloned human brain A3 receptors, determined in competitive binding assays versus [125I]AB-MECA [N6-(4-amino-3- iodebenzyl)adenosine-5'-(N-methyluronamide)]. Affinity was determined in radioligand binding assays at rat brain A1 and A(2A) receptors using [3H]- N6-PIA ([3H]-(R)-N6-phenylisopropyladenosine) and [3H]CGS21680 [[3H]-2- [[4-(2-carboxyethyl)phenyl]ethylamino]-5'-(N-ethylcarbamoyl)adenosine], respectively. The triethyl and tripropyl ether derivatives of the flavonol galangin, 4, had K(i) values of 0.3-0.4 μM at human A3 receptors. The presence of a 5-hydroxyl group increased selectivity of flavonols for human A3 receptors. The 2',3,4',7-tetraethyl ether derivative of the flavonol morin, 7, displayed a K(i) value of 4.8 μM at human A3 receptors and was inactive at rat A1/A(2A) receptors. 3,6-Dichloro-2'-(isopropyloxy)-4'- methylflavone, 11e, was both potent and highly selective (~200-fold) for human A3 receptors (K(i) = 0.56 μM). Among dihydroflavonol analogues, the 2-styryl instead of the 2-aryl substituent, in 15, afforded selectivity for human A3 vs rat A1 or A(2A) receptors. The 2-styryl-6-propoxy derivative, 20, of the furanochromone visnagin was 30-fold selective for human A3 receptors vs either rat A1 or A(2A) receptors. Several of the more potent derivatives effectively antagonized the effects of an agonist in a functional A3 receptor assay, i.e. inhibition of adenylyl cyclase in CHO cells expressing cloned rat A3 receptors. In conclusion, these series of flavonoids provide leads for the development of novel potent and subtype selective A3 antagonists.

Interactions of flavonoids and other phytochemicals with adenosine receptors.

Flavone derivatives and other phytochemicals were found to bind to three subtypes of adenosine receptors in the micromolar range. Affinity was determined in radioligand binding assays at rat brain A1 and A2A receptors using [3H]-N6-PIA ([3H]-(R)-N6-phenyl

Synthesis of 5-Hydroxy-3,7,8,2',4'-pentamethoxyflavone

The title flavone (II) has been synthesised starting from 2'-hydroxy-2,4,4',6'-tetramethoxychalkone (VII).VII on treatment with H2O2 in the presence of alkali gives 3-hydroxy-5,7,2',4'-tetramethoxyflavone (III), which on methylation affords 3,5,7,2',4'-pe

STRUCTURAL ELUCIDATION OF POLYMETHOXYFLAVONES FROM SHIFT REAGENT PROTON NMR MEASUREMENTS

Key Word Index - Polymethoxyflavones; 1H NMR; shift reagents; Pr(fod)3; structural elucidation. The quantitative shift reagent behavior of polymethoxylated flavones in the presence of Pr(fod)3 shows that for structural elucidation of these molecules the degree of substitution on the neighbourhood of the carbonyl group can be determined from the number of signals that are strongly shifted and broadened.The induced shifts of the remaining signals are of complementary help and even the resonances of individual methoxy groups can be ascribed.