preferred_name: 1-hexadecanoyl-2-(9Z,12Z-octadecadienoyl)-sn-glycero-3-phosphoethanolamine + N-(acetyl)-sphing-4-enine => 2-(9Z,12Z)-octadecadienoyl-sn-glycero-3-phosphoethanolamine + 1-hexadecanoyl-N-(acetyl)-sphing-4-enine