120116-72-5 (R) 139574-76-8 AIDS-002121 AIDS002121 CP-31 Phosphoether lipid Pyridinium, 1-(7-ethoxy-4-hydroxy-4-oxido-3,5,9-trioxa-4-phosphapentacos-1-yl)-, inner salt rac-1-O-Hexadecyl-2-O-ethylglycero-3-phospho-2-pyridinumethanol