Antioxidant and Anticholinesterase Activities of Some Dialkylamino Substituted 3-Hydroxyflavone Derivatives.
BACKGROUND
Flavones, are a class of naturally occuring polyphenolic compounds which have 2-phenylchromen-4-one structure. Various studies showed that flavones have several pharmacological activities such as antioxidant, anti-inflammatory, antimicrobial, cytotoxic, antitumour and antiallergic. In the present study, 3-hydroxyflavones also called flavonols, posessing 4'-dialkylamino moiety were synthesized, and their antioxidant and anticholinesterase activities were investigated by comparison with unmodified 3-hydroxflavone.


METHODS
For investigation of antioxidant potential, radical scavenging assays (DPPH•, ABTS+_, O2.-) were used along with CUPRAC and lipid peroxidation inhibitory assays, as well as anticholinesterase activity by Ellman method.


RESULTS
The best results were obtained for 4'-N,N-dimethyl flavonol (1) in both antioxidant and anticholinesterase activity tests, possibly due to its least steric hinderance effect. It exhibited remarkable DPPH free radical scavenging activity (2.43±0,09 μg/mL) competing with a standard compound quercetin (2.10±0,10 μg/mL). Moreover, the other tested flavonols also showed high antioxidant activities. Compounds 5 and 6 exhibited close IC50 values to those of compound 1.


CONCLUSIONS
Antioxidant activity test results were found to be well correlated with anticholinesterase activity test results indicating possible role of antioxidant compounds in the treatment of Alzheimer's disease.
Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Istanbul, Turkey.
Burcu
B
Culhaoglu
Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, Istanbul, Turkey.
Asli
A
Capan
Department of Pharmaceutical Technology, Faculty of Pharmacy, Dicle University, Diyarbakir, Turkey.
Mehmet
M
Boga
Department of Chemistry, Faculty of Science, Mugla Sitki Kocman University, Mugla, Turkey.
Mehmet
M
Ozturk
Chemistry Group, Organic Chemistry Laboratory, TUBITAK UME, Gebze, Kocaeli, Turkey.
Turan
T
Ozturk
Department of Pharmacognosy/ Phytochemistry, Faculty of Pharmacy, Bezmialem Vakif University, Istanbul, Turkey.
Gulacti
G
Topcu
D000110:Acetylcholinesterase / Q000378:metabolism*; D000975:Antioxidants / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002800:Cholinesterase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D013329:Structure-Activity Relationship
D000975:Antioxidants; D002800:Cholinesterase Inhibitors; D005419:Flavonoids; D000110:Acetylcholinesterase; C041477:3-hydroxyflavone
3-hydroxyflavone; Alzheimer's disease; anticholinesterase; antioxidant; flavonoid; flavonol