These unusual glycolipids were found in marine sponges. Various forms were described but they have in common a ceramide-like structure with cyclopropane-containing carbon chains (fatty acid and base) and one or two prenylated galactose residues (Costantino V ET AL., J Am Chem Soc 1997, 119, 12465; Tetrahedron 2000, 56, 5953).

These lipids were shown to be strongly immunosuppressive on activated T cells.