sphingosine metabolic process diol biosynthetic process sphingosine biosynthetic process The chemical reactions and pathways resulting in the formation of sphingosine (sphing-4-enine), trans-D-erytho-2-amino-octadec-4-ene-1,3-diol, a long chain amino diol sphingoid base that occurs in most sphingolipids in animal tissues. sphingosine anabolism sphingosine biosynthesis sphingosine synthesis biological_process sphingosine formation GO:0046512 sphingoid biosynthetic process