Unusual Fernane and Gammacerane Glycosides from the Aerial Parts of <i>Spergula fallax</i>

Abstract

The aerial parts of <i>Spergula fallax</i> afforded four glycosides (<b>1</b>–<b>4</b>) based on two new triterpene aglycones (<b>1a</b> and <b>2a</b>), along with the known hopane glycoside succulentoside A. Compound <b>1</b> was identified as belonging to the fernane class, unusual migrated hopane triterpenoids, mainly isolated from ferns and only rarely from higher plants. Compounds <b>2</b>–<b>4</b> were assigned as gammacerane glycosides, having as aglycone a hydroxylated derivative of tetrahymanol. The structures of the isolated compounds <b>1</b>–<b>4</b> and their aglycones <b>1a</b> and <b>2a</b> obtained by acid hydrolysis were elucidated by spectroscopic data interpretation. The growth inhibitory activity of the isolated compounds and their aglycones was evaluated against the HeLa and DLD-1 cancer cell lines