Functionalization of Betulinic Acid with Polyphenolic Fragments for the Development of New Amphiphilic Antioxidants.

ABSTRACT: The present work aimed at the valorization of biomass derived compounds by their transformation into new added-value compounds with enhanced antioxidant properties. In this context, betulinic acid (BA) was decorated with polyphenolic fragments, and polyhydroxylated (E)-2-benzylidene-19,28-epoxyoleanane-3,28-diones 4a-d were obtained. For that, the synthetic strategy relied on base-promoted aldol condensation reactions of methyl betulonate, which was previously prepared from natural BA, with appropriate benzaldehydes, followed by cleavage of the methyl protecting groups with BBr3. It is noteworthy that the HBr release during the work-up of the cleavage reactions led to the rearrangement of the lupane-type skeleton of the expected betulonic acid derivatives into oleanane-type compounds 4a-d.

SUBMITTER: Sousa JLC 

PROVIDER: S-EPMC7909560 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature