New glycosphingolipid containing an unusual sphingoid base from the basidiomycete Polyporus ellisii

A new 9-methyl-sphinga-4,8-dienine-containing glucocerebroside (1), togethe r with two additional known analogs, cerebrosides B and D, was isolated fro m the chloroform-soluble lipid fraction of the ethanol and chloroform/metha nol extract of the fruiting bodies of the basidiomycete Polyporus ellisii B erk. and characterized. The structure and relative stereochemistry of the n ew compound were identified as (25,3R,4E,8E)-1-(beta -D-glucopyranosyl)-3-h ydroxy-2-[(R)-2'-hydroxyheptadecanoyl]amino-9-methyl-4.8-octadecadiene by m eans of spectroscopic (H-1, C-13, and two-dimensional nuclear magnetic reso nance; mass spectrometry) and chemical methods.