How is 3-(4-Biphenylyl)-3-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}propanoic acid (CAS: 269078-79-7) typically synthesized?

3-(4-Biphenylyl)-3-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}propanoic acid (CAS: 269078-79-7) is synthesized via multistep reactions involving protecting group chemistry, coupling reactions, and amide formation. Commonly, it is prepared using fluoren-9-ylmethanol as a starting material, followed by acylation and coupling with a biphenyl derivative. The reaction conditions typically include the use of base catalysts like DIPEA and coupling agents such as HATU. The yield is generally around 70-80%.