$673.00 - $2020.00
Fmoc-Glu(OtBu)-Val-OH is a protected Glu-Val dipeptide in which the glutamate amino terminus carries Fmoc, the glutamate side-chain gamma-carboxyl group is protected as OtBu, and the C-terminal valine carboxyl group remains free for extension.
Confirm the lot-specific structure and product specification against the Certificate of Analysis.
Product Information
| Product Name | Fmoc-Glu(OtBu)-Val-OH |
| Catalog No. | AS4141 |
| CAS No. | 2897581-02-9 |
| Molecular Formula | C29H36N2O7 |
| Molecular Weight | 524.61 g/mol |
| Chemical Identity | Fmoc-L-Glu(OtBu)-L-Val-OH; alpha-glutamyl Val with side-chain gamma-carboxyl OtBu protection |
| Building Block Type | Fmoc/tBu-protected dipeptide fragment |
| Primary Applications | Glu-Val motif incorporation, protected fragment coupling, convergent peptide synthesis and process-route development |
Alpha vs Gamma Glutamyl Connectivity Must Be Explicit
Glutamate can form amide bonds through either the alpha or gamma carboxyl function, and linkage isomers can share formula and molecular mass. In this product, the intended structure is Fmoc-L-Glu(OtBu)-L-Val-OH: the alpha carboxyl participates in the Glu-Val peptide bond and the gamma side-chain carboxyl is protected as OtBu. This identity should be verified from structure, not inferred from mass alone.
Preformed Fragment vs Stepwise Monomers
A stepwise route can use Fmoc-Glu(OtBu)-OH followed by Fmoc-Val-OH. The preformed fragment removes formation of the internal Glu-Val bond from the downstream route and can be useful when the motif is repeated or the later intermediate is already crowded.
Valine Still Creates Downstream Steric Demand
Val is beta-branched, so coupling through or adjacent to the Val residue may be more demanding than coupling at a small residue. A preformed Glu-Val bond solves only the bond already present in the fragment. It does not guarantee that the next chain-extension step will be easy. Our discussion of incomplete coupling and aggregation in SPPS is relevant when Val-rich sequences show deletion impurities.
Procurement and QC Considerations
Confirm CAS 2897581-02-9, formula C29H36N2O7, MW 524.61 g/mol, L-Glu/L-Val stereochemistry, alpha-Glu-Val connectivity and gamma-OtBu protection. For linkage-sensitive intermediates, we recommend reviewing the drawn structure and lot-specific analytical data rather than relying only on shorthand nomenclature.
For sequence-specific routes that combine protected Glu fragments with beta-branched residues, custom peptide synthesis with protected-fragment route planning can be evaluated before 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
Is Fmoc-Glu(OtBu)-Val-OH an alpha- or gamma-glutamyl dipeptide?
The intended structure is an alpha-Glu-Val peptide bond with the glutamate side-chain gamma-carboxyl protected as OtBu.
Why can mass spectrometry not prove alpha vs gamma connectivity?
Linkage isomers can have the same elemental composition and molecular mass, so the drawn structure and structure-specific documentation are needed.
Can the Val carboxyl group be coupled further?
Yes. The C-terminal valine carboxyl group is free and can be activated for chain extension.
Related Technical Resources
Compare the fragment with the two standard monomers linked above. Additional protected dipeptides are available in the specialty peptide building-block collection.