tBuO-Ste-Glu(AEEA-AEEA-OH)-OtBu (CAS 1118767-16-0) is a di-tert-butyl-protected C18 fatty diacid-glutamic acid-bis(AEEA) linker, belonging to the fatty acid-amino acid-PEG linker (side chain) chemical class. This compound is the main building block for the side chain used in the solid-phase peptide synthesis (SPPS) of Semaglutide. This protected side chain is added to Semaglutide at Lys34 through the ε-amino group. This gives the C18 fatty diacid moiety (octadecanedioic acid, Ste), which allows for high-affinity albumin binding (>99% plasma protein bound) and increases the plasma half-life of semaglutide to ~165 hours for once-weekly dosing. Des-AEEA (single AEEA) truncation products, tBu-retained incompletely deprotected species, and C16 (palmitic) vs C18 fatty acid chain-length variants are all examples of impurities that are related to the process.
ApiSyn offers tBuO-Ste-Glu(AEEA-AEEA-OH)-OtBu (CAS 1118767-16-0) as a pharmaceutical-grade SPPS side chain building block for making Semaglutide and checking its quality.
| Chemical Name | (S)-22-(Tert-butoxycarbonyl)-43,43-dimethyl-10,19,24,41-tetraoxo-3,6,12,15,42-pentaoxa-9,18,23-triazatetratetracontanoic acid |
| Molecular Formula | C43H79N3O13 |
| Molecular Weight | 846.1 |
| CAS Number | 1118767-16-0 |