1-stearoyl-2-arachidonoyl-sn-glycero-3-phosphoethanolamine (SAPE) is a 1,2-diacyl-sn-glycero-3-phosphoethanolamine in which the acyl substituents at positions 1 and 2 are specified as stearoyl and arachidonoyl respectively. It is used in the preparation of liposomes.