High Efficiency Solid Phase Peptide Synthesis (HE-SPPS) — ASN Events
  1. Schedule
  2. Session 7 SPPS Automation, Materials & Applications
  3. High Efficiency Solid Phase Peptide Synthesis (HE-SPPS)

High Efficiency Solid Phase Peptide Synthesis (HE-SPPS) (#27)

Jonathan M Collins 1 , Keith A Porter 1 , Sandeep K Singh 1 , Grace S Vanier 1
  1. CEM Corporation, Matthews, NC, United States

An optimized process for SPPS is presented that allows for complete cycle times of only 4 minutes along with a major reduction (approximately 90%) in total chemical waste compared to traditional methods. Key features of this process are newly developed microwave enhanced reaction conditions, a novel low cost deblocking cocktail, low cost in-situ carbodiimide based activation, optimized washing, and ultra-fast automation. This new process was initially tested on a series of 6 difficult peptides and has met or exceeded the maximum purity observed under any method. Further improvements were then achieved through a new hydrophilic resin as well as a recently developed histidine derivative1.

A more recent a-amino protecting group (Bsmoc)2,3 containing an unsaturated a,b-sulfone moiety removeable through a Michael Addition mechanism was then utilized. Advantages of Bsmoc protection compared to Fmoc are a higher base lability, avoidance of dibenzofulvene capping during solution phase synthesis methods, and increased solubility in aqueous and alcohol solvents. However, a significant limitation of the Bsmoc group is it often produces amino acid derivatives as oils thereby making them difficult to handle. This was addressed by the development of a new protecting group (Dmoc) which features similar advantages to Bsmoc protection, but allows all of the common amino acid derivatives to be produced as solids. Scalable routes for the Dmoc protecting group are described and appear economical.

It was subsequently demonstrated that the optimized washing steps that traditionally employ DMF/NMP can be replaced with EtOH thereby further reducing undesirable solvent usage. The scalability of this method appears feasible as demonstrated by the development of a 2.5 liter microwave peptide synthesizer. This new process for SPPS should have a major impact on synthesis of difficult peptides, high throughput peptide production, and larger scale peptide production as it offers improvements in speed, chemical usage, and synthesis efficiency.

  1. [1] Hibino, H., Miki, Y., Nishiuchi, Y. J. Pept. Sci. 2012, 18, 763.
  2. [2] Carpino, L.A., Philbin, M., Ismail, M., Truran, G.A., Mansour, E.M.E., Iguchi, S., Ionescu, D., El-Faham, A., Riemer, C., Warrass, R., and Weiss, M.S. J. Am. Chem. Soc. 1997, 119, 9915.
  3. [3] Carpino, L.A., Ismail, M., Truran, G.A., Mansour, E.M.E., Iguchi, S., Ionescu, D., El-Faham, A., Riemer, C., and Warrass, R. J. Org. Chem. 1999, 64, 4324.