$1785.71 - $5357.14
Fmoc-Gly-Gly-OH is an N-Fmoc-protected diglycine fragment with a free C-terminal carboxyl group. It supplies a defined Gly-Gly unit as one building block and can be extended through peptide-bond formation without first assembling the two glycine residues separately.
For researchers comparing protection strategies, Z-Gly-Gly-OH provides the same Gly-Gly sequence under Cbz protection rather than Fmoc. The sequence motif is the same, but temporary N-protection and downstream deprotection chemistry are different.
Product Information
| Product Name | Fmoc-Gly-Gly-OH |
| Catalog No. | AS2062 |
| CAS No. | 35665-38-4 |
| Molecular Formula | C19H18N2O5 |
| Molecular Weight | 354.36 g/mol |
| Building Block Type | Fmoc-protected Gly-Gly dipeptide fragment |
| Primary Applications | Fmoc-compatible fragment coupling; Gly-Gly motif installation; flexible linker construction; peptide and conjugate synthesis |
Why Use a Preformed Gly-Gly Fragment
A preassembled dipeptide removes one coupling step from the downstream route and provides a separately characterized Gly-Gly unit. This can be useful in repetitive linker chemistry, fragment synthesis, and routes where a short flexible motif is used across several analogs. For a straightforward one-off peptide, stepwise assembly from individual glycine residues may still be simpler.
Fmoc Protection Fits Base-Labile N-Terminal Control
The Fmoc group allows the N-terminus to remain protected during carboxyl activation and fragment coupling, then be removed under standard base-mediated conditions. Researchers using this fragment within a conventional resin workflow can review the current SPPS practical guide for the broader chain-assembly context.
Gly-Gly Is Flexible, but Chain Length Still Matters
Glycine has minimal side-chain steric bulk, so a Gly-Gly segment can provide a short flexible spacer. It is not chemically equivalent to Gly3, Gly4, PEG, Ahx, or another linker. Spacer length, polarity, proteolytic behavior, and distance between attached groups should be selected for the final construct rather than inferred from the word 'flexible'.
Procurement and Analytical Control
Confirm CAS 35665-38-4, formula C19H18N2O5, MW 354.36 g/mol, the exact Gly-Gly chain length, and N-terminal Fmoc protection. Short oligoglycine fragments can differ by one glycine residue, so LC-MS is especially useful for confirming chain length while HPLC provides complementary purity information.
For a complete peptide or linker-containing construct, Alan Scientific can evaluate whether stepwise assembly or preformed fragment use is more appropriate through custom peptide synthesis.
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-Gly-OH used for?
It is used as a protected Gly-Gly fragment for peptide synthesis, linker construction, and convergent assembly.
Is the C-terminal carboxyl group free?
Yes. The terminal glycine carboxyl group is available for activation and further coupling.
Why choose a preformed dipeptide?
It can reduce one downstream coupling step and provides a separately characterized Gly-Gly unit.