Reaction mechanisms in peptide synthesis

Peptide synthesis can be performed in solution (liquid phase) or in solid phase

used for peptide synthesis under harsh reaction ..

SynPhase Lanterns are modular solid substrates that hold discrete quantities of single compound and are optimized for the synthesis of small organic molecules or peptides, as well as extracting contaminants or final products from solution-phase reactions. Their modular design and propensity for tagging makes SynPhase Lanterns adaptable to various synthesis strategies and methodologies.

10. Galanis AS, Albericio F, Grotli M. Solid-phase peptide synthesis in water using microwave-assisted heating.  2009;11:4488-91

Solid Phase Peptide Synthesis - RealPeptide

Peptides are synthesized on Protein Technologies "Symphony" instruments using FMOC based chemistry and uronium salt type activation methodologies, such as HATU/HOBt/DIEA activation. This chemistry provides for faster synthesis cycles, better coupling kinetics, and greatly improved coupling efficiencies. These improvements result in faster turnaround times and lower prices for peptide synthesis. Additionally, FMOC peptides can be cleaved using a trifluoroacetic acid/cation scavenger cocktail, obviating the need for costly and time consuming HF or TFMSA cleavages required for t-Boc peptide synthesis. At this time t-Boc synthesis is not used for the production of peptides in the Peptide Synthesis Laboratory.

13. Sabatino G, Papini AM. Advances in automatic, manual and microwave-assisted solid-phase peptide synthesis.  2008;11:762-70

A single SynPhase Lantern is required for the synthesis of each compound in quantities less than 40mg. For larger scale syntheses, SynPhase Lanterns may be pooled to generate the required quantity of compound. The cost of the solid support, whether it is a SynPhase Lantern or resin, depends upon the type of functionality required for synthesis. The direct cost of SynPhase Lanterns in general terms on a per loading basis ($/mmol) is in the same range as high quality resins.

14. Moss JA. Guide for resin and linker selection in solid-phase peptide synthesis.  2005 Chapter 18: Unit 18.7

Peptide Synthesizer, Automated Peptide Synthesizer

In this last step of the synthesis the peptide is cleaved from the resin together with the side chain protecting groups at the exception of the ones which are orthogonal to this acidolytic reaction.

Peptide Sequencing and Synthesis - WWW Project Top …

Merrifield has rapidly realized that the relative labilities towards acid of the Boc and benzyl groups would be compatible with an effective temporary vs. permanent protecting scheme and very soon published the solid phase synthesis of Bradykinin using Boc protected amino acids [14].

Liberty Blue - Automated Microwave Peptide Synthesizer

Also small scale manual SPPS as well as multiple peptide synthesis and the synthesis of pep- tide libraries can be performed very rapidly and conveniently with preformed active esters. Fmoc-AA-ONp and Fmoc-AA-OSu have found only restricted application in SPPS.

Practical Asymmetric Synthesis of a Calcitonin Gene-Related Peptide …

As mentioned above, the generation and disappearance of Fmoc based chromophors allows the monitoring of the synthesis. Furthermore, samples may be taken to determine the load of Fmoc peptide. The completion of the deprotection reaction may be checked by cleaving samples and analyzing the obtained peptide.

A low tendency for racemization is a key requirement

But, whichever cleavage reagent is preferred, it has to be washed out very carefully after Fmoc removal, the last washing must be neutral. When synthesizing large peptides the duration of Fmoc cleavage should be gradually increased. For safe removal of the deblocking reagent the resin may have to be washed more often.

Glossary | Linus Pauling Institute | Oregon State University

SiO2--pSt hybrid nanoparticles with each tethered polystyrene possessing molar masses in the range of Mn = 5,000 to 33,000 g/mol were prepared using commercially available silica nanoparticles as colloidal initiators, which greatly facilitated scale-up synthesis. The hybrid particles were characterized both in the solid state and in solution using transmission electron microscopy (TEM) and dynamic light scattering (DLS) respectively. TEM images of the SiO2--pSt colloids revealed the formation of (sub)monolayer patches with interparticle spacing that increased with an increase in the molar mass of the tethered polystyrene. Comparison of the hydrodynamic radii (Rh) of hybrid nanoparticles of varying size determined by DLS in toluene, versus the molar mass (Mn) of the polystyrene chains cleaved from colloids, determined by SEC, revealed a linear relationship. Such a linear dependence of Rh Mn is a strong indication that when the particles are dispersed in toluene, the tethered chains adopt highly chain extended conformations, presumably due to steric interactions caused by the high grafting density. (29)