Fmoc protecting group is used to protect amine group of peptides/proteins. Fmoc group can be removed to generate a free amine using a very mild basic condition. Additionally, special resins for Fmoc deprotection are also available on the market. In some synthetic strategies, Fmoc is preferred over t-Boc protecting group because t-Boc requires very strong acid to cleave and this may cause some issues with acid-labile side-chain protecting groups of the peptides.