Ent-kaurane-typediterpenoidsarewidespreadinnumerousplantsources[1]andsome representativesarereadilyavailableforlargescaleisolation.Themostknown examplesareperhapsent-kaurenoicacid1andsteviol2,whichcanbeconveniently isolatedfrom industrialcrops,derivedproductsorresiduesofagriculture. Thesenaturalcompoundsalonepossessavarietyofinterestingbiologicalproperties and also a lotofSAR studies have been reported basing on theirstructural modification[2].Surprisingly,thereactivityoftheexo-methylenicΔ16,17 doublebond wasmostlyaddressedbasingonheteroatom additionandoxidativetransformations. We focused ourattention on applying radicalprocesses to complex natural structuresasrealusefultoolsforexpandingmolecularcomplexityandsynthesisof newbiologicallyactivecompounds.Severaltransformationshavebeeninvestigated withbothent-kaurenoicacid1andsteviol2,aswellaswiththerelated15-hydroxyent- kaurenoic acid 3.It included radicalhydroazidation,carboazidation and carboiodination[3].Thederivedproducts,inparticularazidessuchas4and5,have beenusedtogenerateaseriesoffunctionalizedent-kauranesforSARstudies. Acknowledgements The presented work was performed within the project “Radical mediated modifications ofnaturalproducts”supported financiallybythe Swiss National ScienceFoundation(SCOPESprogram,projectNo.IZ73Z0_152346/1). References [1]Ghisalberti,E.L.Fitoterapia,1997,63,303. [2]Morarescu,O.ChemistryJournalofMoldova,2015,10(1),9-19. [3]Lapointe,G.,Kapat,A.,Weidner,K.,Renaud,P. Pureandappliedchemistry, 2012,84(7),1633-1641.
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