How is (2S,4E)-2-{[(9H-Fluoren-9-ylmethoxy)carbonyl]amino}-5-phenyl-4-pentenoic acid (CAS: 159610-82-9) typically synthesized?

(2S,4E)-2-{[(9H-Fluoren-9-ylmethoxy)carbonyl]amino}-5-phenyl-4-pentenoic acid (CAS: 159610-82-9) can be synthesized via a multistep process involving the protection of a carboxylic acid, amide formation, and deprotection. Commonly, a protected intermediate is first synthesized, followed by amination with a protected amino reagent. The product is then isolated and purified using column chromatography. The synthesis typically employs mild conditions and mild solvents to ensure high yield and selectivity.