Synthesis and radical scavenger properties of novel spirochromenes derived from steroid sapogenins

•Aldol reaction of sapogenins and salicylaldehyde produced spirochromenes.•Reaction of sapogenins and 2,5-dihydroxybenzaldehyde led to 6′-hydroxyspirochromenes.•The structures were verified with combined mono and bidimensional NMR techniques.•The 6′-hydroxyspirochromenes showed significant antioxidant activity in DPPH test.

Tandem aldol condensation between steroid sapogenins and hydroxylated benzaldehydes afforded steroidal spirochromenes. Compounds that bear a phenolic hydroxyl group at position C-6′, obtained by a reaction with 2,5-dihydroxybenzaldehyde, showed approximately 80% of maximal radical scavenging activity in the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay at 288 nM. In contrast, the starting steroid sapogenins and the spirochromenes without a phenolic group in the side chain proved to be inactive.

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