7622-61-9

Upstream product

• 95626-25-8 2-(3,4-diacetoxy-phenyl)-3,5,7-trimethoxy-chromen-4-one 
• 97434-01-0 3,5,7-Trimethoxy-3',4'-diphenylmethylendioxy-flavon 
• 124458-88-4 3',4'-diacetyloxy-3'-hydroxy-3,7-dimethoxyflavone 
• 2068-02-2 2-(3,4-dihydroxyphenyl)-5-hydroxy-3,7-dimethoxychromen-4-one 

Relevant academic research and scientific papers

Quercetin derivative and its preparation method and application

The invention discloses a quercetin derivative and a preparation method and application thereof. The preparation method comprises the following steps: firstly using dichlorodiphenylmethane to protect quercetin o-diphenol hydroxyl, combining a benzyl protection group to obtain the selectively protected quercetin derivative, and then independently reacting with dimethyl sulfate, diethyl sulfate, allyl bromide, paratoluensulfonyl chloride and acetic anhydride respectively to generate corresponding quercetin derivatives. All of the prepared derivative compounds have NRK-49F proliferation activity inhibition superior to that of quercetin. The quercetin derivatives 20a-1, 14a-1 and 23d-1 compositely replaced by methyl and p-tosyl have higher inhibition NRK-49F proliferation activity, and the inhibition ratio respectively reaches 86.33%, 78.04% and 75.91%. Thus, the currently obtained quercetin derivative compounds have obvious inhibition effect on kidney fibroblast NRK-49F proliferation.

ANTIMICROBIAL FLAVONOIDS FROM PSIADIA TRINERVIA AND THEIR METHYLATED AND ACETYLATED DERIVATIVES

Key Word Index - Psiadia trinervia; Compositae; flavonoids; antifungal; antibacterial; Cladosporium cucumerinum; Bacillus cereus; bioautography.Abstract - From a dichloromethane extract and a hydrolysed methanolic extract from the leaves of Psiadia trinervia, 13 3-methylated flavonol have beeen isolated.Their structures were established by the usual spectoscopic methods (UV, EIMS, 1H and 13CNMR).Ayanin, casticin, chrysosplenol-D and 5,7,4'-trihydroxy-3,8-dimethoxyflavone were responsible for the antifungal activity found in the preliminary screening.Chrysosplenol-D, isokaemferide, 5,7,4'-trihydroxy-3,3'-dimethoxyflavone and 5,7,4'-trihydroxy-3,8-dimethoxyflavone displayed antibacterial activity.Twenty-nine derivatives were prepared by permethylation and selective methylation of the free hydroxyl group at C-5.The antimicrobial activities of the isolates and derivatives were determined by bioautographic assays using C. cucumerinum and B. cereus as test organisms.