Peptide/Amide Bond Strategies With T-Bec®
Designed for use in SPPS. T-Bec® carbodiimide surpasses DIC in terms of efficiency, making it a more effective coupling reagent. T-Bec® employs the same coupling protocols as other carbodiimides, ensuring seamless integration into existing chemical processes.
| Temperature conditions | Fmoc deprotection | Coupling | Washing | Peptide model | Purity (HPLC) % |
| Induction heating 90oC | AcOBu:DMSO:Piperidine 3.2:4.8:2 (v/v) | AcOBu:DMSO 7:3 (v/v) Fmoc-AA (0.2M) TBEC (0,5M) OxymaPure (0,5M) | AcOEt:DMSO 8:2 (v/v) | GTPstd-NH2 AKADEVSLHKWYG-NH2 | 93.3 |
Microwave-assisted synthesis
| Peptide model | Liraglutide: HAEGTFTSDVSSYLEGQAAK(γ-E-palmitoyl)-EFIAWLVRGRG-OH |
| Instrument | CEM liberty PRIME 2.0 |
| Synthesis scale | 0.1mmol |
| Deprotection method | 80 sec (110oC) |
| Fmoc-AA-OH | 0.50M in DMF, 1.0 ml ( 5 Equiv.) |
| T-Bec | 0.75 M in DMF, 1.0 ml (7.5 Equiv.) |
| OxymaPure | 0.26 M in DMF, 1.5ml (4 Equiv.) |
| Coupling method | 30 sec wait + 60 sec (105oC) |
| Cleavage | TFA/TIS/Water/DODT/anisole(85/2.5/2.5/5.0/5.0); 30 min at 38°C |
| Lyophilization | Peptide sample was dissolved in 10% acetic acid/water and lyophilized overnight before UPLC-MS analysis |
Manual synthesis of challenging/difficult peptides
Reaction Conditions: Solid-phase peptide synthesis (SPPS) on Rink amide resin, using 5 equivalents of reagents, in situ activation in DMF at 25°C for 30 minutes.
| Entry | Peptide | Purity (%) |
| 1 | Leu-enkephalin | 96.70% |
| 2 | Ile2,3-Leu-enkephalin | 96.60% |
| 3 | 65 74 ACP | 96.12% |
| 4 | ABRF92 | 74.53% |
| 5 | H-A10K3-NH2 | 87.93% |
Racemization study (Dl/LL, %)
| Entry | peptide | Dl/LL (%) |
| 1 | H-Gly-His-Phe-NH2 | 1.05% |
| 2 | H-Gly-Cys-Phe-NH2 | N.D |
| 3 | H-Gly-Ser-Phe-NH2 | 0.29 |