$1033.00 - $3101.00
Z-Phe-Gly-OH, also written Cbz-L-Phe-Gly-OH, is an N-Cbz-protected Phe-Gly dipeptide with a free glycine C-terminal carboxyl group. It provides the Phe-Gly sequence as a defined short fragment for additional amide-bond formation.
Phenylalanine contributes an aromatic hydrophobic side chain, while glycine removes side-chain steric bulk at the second residue. The fragment is useful in protected peptide assembly and solution-phase synthesis when a preverified Phe-Gly bond is preferred over sequential construction.
Product Information
| Product Name | Z-Phe-Gly-OH |
| Catalog No. | AS4132 |
| CAS No. | 13122-99-1 |
| Molecular Formula | C19H20N2O5 |
| Molecular Weight | 356.37 g/mol |
| Chemical Identity | Cbz-L-Phe-Gly-OH; Z-Phe-Gly-OH |
| Building Block Type | Cbz-protected dipeptide fragment |
| Primary Applications | Protected fragment coupling, Phe-Gly motif incorporation, solution-phase peptide synthesis and analytical route development |
Sequence Order Is a Chemical Identity Parameter
Phe-Gly and Gly-Phe have the same amino-acid composition and can share the same nominal molecular formula after identical terminal protection. They are still different molecules. Routine MS may confirm mass but cannot establish sequence order by itself. We recommend verifying the drawn structure and the Phe-Gly direction on the COA rather than relying on the phrase “Phe/Gly dipeptide.”
Why Use a Cbz-Protected Fragment?
Cbz protection is common in solution-phase and protected-fragment chemistry and is typically removed under reductive conditions. This can be useful when a route is not built around repeated Fmoc cycles. The tradeoff is compatibility: unsaturated or other reduction-sensitive functionality elsewhere in the molecule may influence when Cbz removal should occur.
Aromatic Phe in Peptide Route Design
Phe-containing fragments can contribute to hydrophobicity and aromatic packing as the sequence grows. Researchers sourcing additional aromatic building blocks can compare this fragment with Alan's phenylalanine and tryptophan building-block portfolio. In longer hydrophobic sequences, crude solubility and purification can become as important as the local coupling step.
Procurement and QC Considerations
Confirm CAS 13122-99-1, formula C19H20N2O5, MW 356.37 g/mol, L-Phe stereochemistry, N-terminal Cbz protection and the free Gly carboxyl. For sequence-defined standards or fragment synthesis, HPLC and MS should be interpreted together with the exact structural record.
If a protected Phe-Gly fragment is being incorporated into a longer custom sequence, peptide synthesis for aromatic and fragment-based sequences can be reviewed together with target purity and scale.
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 Z-Phe-Gly-OH used for?
It is used as a Cbz-protected Phe-Gly dipeptide fragment in solution-phase peptide synthesis and protected-fragment assembly.
Is Z-Phe-Gly-OH the same as Z-Gly-Phe-OH?
No. Reversing the sequence creates a different compound even though the amino-acid composition is unchanged.
How is the Z/Cbz group normally removed?
Cbz is commonly removed under reductive conditions, subject to compatibility with the rest of the molecule.
Related Technical Resources
For the mechanics of extending short peptide fragments, review peptide coupling and chain-assembly fundamentals. Other preassembled motifs can be compared in the specialty building-block collection.