Three isobutyl analogs of phospholipids - isobutyl phosphoric acid (IPA), analog of phosphatidic acid; isobutyl phosphoethanolamine (IPE), analog of phosphatidylethanolamine; and isobutyl phosphocholine (IPCh), analog of phosphatidylcholine - were synthesized for use in mixed crystals as initial material for modeling biomembrane fragments. Isobutyl oxophosphodichloride served as a common precursor yielding IPA when hydrolyzed. Cyclic compounds of the former with ethanolamine and ethylene glycol were used to synthesize IPE and IPCh. The structure of the obtained compounds was identified by means of NMR. For all three compounds the following signals were registered (ppm): 0.9, d, 6H, (CH₃)₂CH-; 1.9, m, 1H, (CH₃)₂CH-; 3.7, t, 2H, -P-O-CH₂-CH(CH₃)₂; which can be attributed to the isobutyl radical. In addition, the following signals were registered for IPE: 3.3, t, 2H, -P-O-CH₂-CH₂-NH₂; 4.1, m, 2H, -P-O-CH₂-CH₂-NH₂; and for IPCh: 3.2, s, 9H, -CH₂-CH₂-N⁺(CH₃)₃; 4.2, m, 2H, -P-O-CH₂-CH₂-N⁺(CH₃)₃. X-ray analysis of the crystals is in progress as part of model studies of the biomembrane organization.