Prenylated Flavonoids as Valuable Biologically Active Compounds from Hops

Synthesis and characterization of 2-thiophen flavonoid analogue for free radical scavenging antioxidant analysis

Introduction and Aim: Currently research is focussed on the use of antioxidants in preventing oxidative stress induced diseases. Flavonoids present in plant sources gaining more therapeutic importance due to their antioxidant property, but their solubility and some pharmacokinetic concern, diverted   the current research study towards the synthesis of these flavonoids for their therapeutic potential.  The study was aimed to synthesize and characterize the 2-thiophen flavonoid analogue for free radical scavenging antioxidant activity.   Materials and Methods: The test synthetic compound PNF(3-hydroxy-2-(thiophen-2-yl)-4H-chromen-4-one) a thiophen substituted flavonoid was synthesized from condensation fallowed cyclization reaction in laboratory and DPPH, superoxide, nitric oxide, and hydroxyl radical  scavenging  activity was determined through established in vitro methods.   Results: It suggests that the test flavonoid (PNF) possesses the potent free radical scavenging on DPPH, superoxide, nitric oxide, and hydroxyl radicals with IC50 values of 6.89±25?g/ml,4.04?g/ml, 2.44?g/ml and 2.96?g/ml respectively. The radical scavenging potential of test PNF synthetic compound at different concentrations(10?g-150?g) was compared with that of standard antioxidants such as BHA , ascorbic acid used in the study.   Conclusion: Results from this study indicates that the novel flavonoid PNF exhibited the considerable dose dependant invitro antioxidant activity. These possible activities could be useful to consider the novel synthetic thiophen derived flavonoid as therapeutic antioxidant agent.

The Antioxidant Activity of Prenylflavonoids

Prenylated flavonoids combine the flavonoid moiety and the lipophilic prenyl side-chain. A great number of derivatives belonging to the class of chalcones, flavones, flavanones, isoflavones and other complex structures possessing different prenylation patterns have been studied in the past two decades for their potential as antioxidant agents. In this review, current knowledge on the natural occurrence and structural characteristics of both natural and synthetic derivatives was compiled. An exhaustive survey on the methods used to evaluate the antioxidant potential of these prenylflavonoids and the main results obtained were also presented and discussed. Whenever possible, structure-activity relationships were explored.