Compounds derived from glycerol in which a primary and the secondary hydroxy groups are esterified with long-chain fatty acids, and the remaining primary one with the mono(2-aminoethyl) ester of phosphoric acid, or with the monoserine ester of phosphoric acid. The term is not recommended. These compounds are preferably designated as (3-phosphatidyl)ethanolamines and (3-phosphatidyl)serines respectively.