A New Ceramide from Suillus luteus and Its Cytotoxic Activity against Human Melanoma Cells

A new phytosphingosine‐type ceramide, suillumide ( 1 ), was isolated from the EtOH extract of the basidiomycete Suillus luteus (L.) S. F. Gray , along with ten known compounds: ergosta‐4,6,8(14),22‐tetraen‐3‐one, ergosterol, ergosterol peroxide, suillin, ( E )‐3,4,5‐trimethoxycinnamic alcohol, 5 α ,6 α ‐epoxyergosta‐8,22‐diene‐3 β ,7 β ‐diol, ( R )‐1‐palmitoylglycerol, ergosta‐7,9(11),22‐triene‐3 β ,5 α ,6 β ‐triol, cerevisterol, and 4‐hydroxybenzoic acid. The structure of 1 was determined on the basis of spectroscopic and mass‐spectrometric analyses, as well as by chemical methods. Compound 1 and its synthetic diacetyl derivative 2 were tested for their cytotoxic activities against the human melanoma cell line SK‐MEL‐1. Both drugs showed IC 50 values of ca. 10 μ M after 72 h of exposure.