A main component of ganglioside M5 from egg of the sea urchin, Anthoci
daris crassispina, Neu5Gc alpha 2-->6Glc beta 1-->1Cer (1), which has
N-glycolyl group in neuraminic acid part, as well as phytosphingosine
and saturated nonhydroxy fatty acid in ceramide part was first synthes
ized starting from N-acetylneuraminic acid.