HBTU, introduced in 1978, is an aminium-based coupling reagent for peptide synthesis. Since then, HBTU has become one of the most popular coupling reagents for amide bond formation under both solution and solid phases synthesis.
Advantages of using HBTU:
Low Cost: Comparing to its analogs HATU and HCTU, the cost for HBTU is much lower.
Excellent Activation: For most amide bond formation with primary amine, HBTU showed good activating efficiency under mild conditions.
Racemization Suppression: It was found that HBTU activation could reduce the racemization to negligible level.
Good Solubility and Stability: HBTU can easily dissolve in most common organic solvents like DMF and NMP, and shows good tolerance to water.
High Yield: For most peptide synthesis with common amino acids, high yields of the products could be obtained if the peptide length is not very long.