$100.00 - $300.00
Fmoc-Gly-Ala-OH is an N-Fmoc-protected Gly-Ala dipeptide with a free alanine C-terminal carboxyl group. It supplies the Gly-Ala sequence as a single characterized fragment and can be extended through the Ala carboxyl in solution-phase or peptide-fragment coupling workflows.
Glycine is achiral, while the alanine residue carries the stereochemical information in this fragment. This makes exact sequence direction and L-Ala identity important procurement parameters even though the fragment is chemically simple.
Product Information
| Product Name | Fmoc-Gly-Ala-OH |
| Catalog No. | AS4128 |
| CAS No. | 71952-99-3 |
| Molecular Formula | C20H20N2O5 |
| Molecular Weight | 368.39 g/mol |
| Chemical Identity | Fmoc-Gly-L-Ala-OH |
| Building Block Type | Fmoc-protected dipeptide fragment |
| Primary Applications | Gly-Ala motif incorporation, fragment coupling, convergent peptide synthesis and route development |
Preformed Fragment vs Stepwise Gly and Ala Coupling
A stepwise route can use Fmoc-Gly-OH and Fmoc-Ala-OH. Using Fmoc-Gly-Ala-OH instead removes one peptide-bond-forming operation and lets the Gly-Ala bond be qualified before the fragment enters a longer sequence. We consider that useful in repetitive motif synthesis or convergent routes, but unnecessary when routine SPPS is already clean and efficient.
Why Sequence Direction Still Matters
Gly-Ala and Ala-Gly contain the same amino-acid composition but are different sequence isomers. The molecular formula alone therefore does not describe which residue is N-terminal. For this product, the Fmoc group is on Gly and the free C-terminal carboxyl belongs to Ala. Procurement records should preserve that sequence direction explicitly.
Coupling Through the C-Terminal Ala
The Ala carboxyl can be activated for further extension. Although alanine is generally a straightforward residue, activation conditions should still minimize unnecessary epimerization at its alpha center. Our practical guide to peptide coupling and Fmoc cycles provides context for how activation, deprotection and chain extension fit together.
Procurement and QC Considerations
Confirm CAS 71952-99-3, formula C20H20N2O5, MW 368.39 g/mol, Fmoc-Gly-L-Ala sequence direction and lot-specific HPLC/MS identity. If the product is being used as a process intermediate, check whether the purity specification controls closely related deletion or sequence impurities rather than relying only on the nominal assay.
For projects where preassembled fragments are being used to shorten a longer route, custom peptide synthesis with fragment and sequence-specific route review is available for research-scale production.
Product Documents
A Safety Data Sheet (SDS / MSDS) is available for this product to support laboratory handling, storage and safety assessment.
Certificates of Analysis (COAs) are batch-specific. Please contact us to request the COA for your product, and we will provide it by email.
Frequently Asked Questions
What is Fmoc-Gly-Ala-OH used for?
It is used as a protected Gly-Ala dipeptide fragment for peptide extension, convergent assembly and preparation of Gly-Ala-containing intermediates.
Is Fmoc-Gly-Ala-OH the same as Fmoc-Ala-Gly-OH?
No. Sequence direction is different, even though both fragments contain one glycine and one alanine residue.
Which carboxyl group is free?
The C-terminal alanine carboxyl group is free and can be activated for further coupling.
Related Technical Resources
Additional short protected fragments are available in the specialty peptide building-block collection. Use the monomer links above when deciding whether a fragment or a stepwise route is more appropriate.