Stigmastane or 24R-ethylcholestane is a tetracyclic triterpene, along with cholestane and ergostane, this sterane is used as a biomarker for early eukaryotes.
See also Stigmastanol (Stigmastan-3β-ol) β-Sitosterol (Stigmast-5-en-3β-ol) Stigmasterol (Stigmast-5,22-dien-3β-ol)
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