$137.00 - $413.00
Ac-Lys(Z)-OH is Nalpha-acetyl-Nepsilon-Cbz-L-lysine. The alpha-amino group is capped as an acetamide, while the lysine epsilon-amino group is protected with benzyloxycarbonyl (Z/Cbz). The carboxyl group remains free.
The acetyl group is a stable amide, not a temporary Fmoc/Boc-type protecting group. This makes the compound useful when N-terminal acetylation is part of the desired final structure or when a protected lysine derivative is needed in solution-phase chemistry.
Product Information
| Product Name | Ac-Lys(Z)-OH |
| Catalog No. | AS4102 |
| CAS No. | 6367-08-4 |
| Molecular Formula | C16H22N2O5 |
| Molecular Weight | 322.36 g/mol |
| Chemical Identity | Nalpha-acetyl-Nepsilon-Cbz-L-lysine |
| Building Block Type | N-alpha-acetyl, side-chain-protected lysine derivative |
| Primary Applications | N-acetyllysine intermediate chemistry, side-chain-protected lysine synthesis and peptide end-group research |
N-Alpha Acetylation Is a Structural Modification
Because the alpha nitrogen is acetylated, it cannot participate in ordinary peptide-chain elongation as a free amine unless the acetyl group is chemically removed under nonroutine conditions. We consider this the main procurement distinction between Ac-Lys(Z)-OH and a standard N-protected lysine monomer.
Why Protect the Epsilon Amine with Cbz
Cbz masks the lysine side-chain amine during transformations at the carboxyl group or elsewhere in the molecule. It can later be removed reductively when compatible with the rest of the structure. The protection pattern is useful when the final target requires Nalpha acetylation but the epsilon amine must remain controlled during synthesis.
Compare with Ac-L-Lys-OH
Ac-L-Lys-OH has the same Nalpha-acetyl motif but a free epsilon-amino group. Ac-Lys(Z)-OH therefore offers side-chain protection, while Ac-L-Lys-OH offers a directly accessible lysine side-chain amine for derivatization. The two products answer different synthetic questions despite sharing the Ac-Lys core.
Procurement and QC Considerations
Confirm CAS 6367-08-4, C16H22N2O5, MW 322.36 g/mol, L stereochemistry and Cbz placement on the epsilon nitrogen. Current supplier safety records classify this material as harmful if swallowed and as a skin, eye and respiratory irritant. The COA should support both identity and purity before the reagent is used in sequence-sensitive 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 does Ac-Lys(Z)-OH mean?
It is Nalpha-acetyl-L-lysine with the epsilon-amino side chain protected by a Cbz/Z group.
Is the alpha acetyl group a routine removable protecting group?
No. It is a stable amide and usually represents part of the intended molecular structure.
How does Ac-Lys(Z)-OH differ from Ac-L-Lys-OH?
Ac-Lys(Z)-OH has a Cbz-protected epsilon amine; Ac-L-Lys-OH leaves the epsilon amine free.
Related Technical Resources
Compare Ac-L-Lys-OH with a free epsilon-amino group.
Discuss N-terminal acetylation or lysine side-chain modification in a custom peptide.