The molecule is a phosphatidylcholine 27:0 in which the acyl groups at positions 1 and 2 are specified as octadecanoyl and nonanoyl respectively. It derives from an octadecanoic acid and a nonanoic acid.
[(2R)-2-nonanoyloxy-3-octadecanoyloxypropyl] 2-(trimethylazaniumyl)ethyl phosphate