(4R)-hydroxysphinganine + a fatty acid => an N-acyl-(4R)-4-hydroxysphinganine + H2O
(4r)-hydroxysphinganine + a fatty acid => an n-acyl-(4r)-4-hydroxysphinganine + h2o
(4R)-hydroxysphinganine + a fatty acid => an N-acyl-(4R)-4-hydroxysphinganine + H2O
(4r)-hydroxysphinganine + a fatty acid => an n-acyl-(4r)-4-hydroxysphinganine + h2o