$344.00 - $1033.00
| Product Name | Fmoc-Tyr-OH |
| Synonyms | Fmoc-L-tyrosine; N-α-Fmoc-L-tyrosine |
| Catalog No. | AS2056 |
| CAS Number | 92954-90-0 |
| Molecular Formula | C24H21NO5 |
| Molecular Weight | 403.43 g/mol |
| SMILES | C1=CC=C2C(=C1)C(C3=CC=CC=C32)COC(=O)N[C@@H](CC4=CC=C(C=C4)O)C(=O)O |
| Storage Temperature | Cool, dry place (≤25°C) |
| Appearance | White to off-white powder |
| Melting Point | 175–185°C (reference) |
| Functional Groups | Fmoc-protected α-amino group; free phenolic hydroxyl; carboxylic acid |
| Primary Application | Fmoc solid-phase peptide synthesis (SPPS) |
Product Overview
Fmoc-Tyr-OH (CAS 92954-90-0; catalog AS2056) is N-Fmoc-L-tyrosine with an unprotected phenolic hydroxyl group. Its alpha-amino group is Fmoc-protected, while the alpha-carboxyl group remains available for activation and peptide-bond formation. This building block is selected when a synthetic route specifically requires access to the tyrosine phenol rather than keeping that group protected throughout assembly.
Free Phenol versus Side-Chain-Protected Tyrosine
The absence of phenolic protection is a structural feature, not a difference in product grade. Fmoc-Tyr-OH and Fmoc-Tyr(tBu)-OH introduce the same L-tyrosine residue after the appropriate processing, but expose different functional groups during synthesis. In conventional Fmoc/tBu solid-phase peptide synthesis (SPPS), a tert-butyl-protected phenol is often preferred when no reaction at that oxygen is intended.
Use the unprotected derivative only after checking the activation, coupling, and any subsequent functionalization steps. An accessible phenol can participate in unwanted reactions as well as planned chemistry; its availability does not establish compatibility with every reagent or protecting-group scheme.
Applications in Tyrosine-Containing Research Peptides
Applications include solution-phase peptide intermediates and route-specific preparation of tyrosine-containing analogues requiring a free phenolic group. For comparisons with phenylalanine-containing sequences, the tyrosine hydroxyl introduces an additional hydrogen-bonding and chemical-functionalization site. Effects on binding, conformation, or solubility must be measured in the finished peptide.
This material is not a phosphotyrosine or sulfotyrosine building block. Projects targeting those modifications require a separately defined installation and protection strategy.
Procurement and Quality Documentation
Quote AS2056 and the required quantity. Confirm chemical identity, L-configuration, and the absence of a side-chain protecting group when matching a procurement specification. Agree any additional analytical requirements before ordering.
Product Documents
A Safety Data Sheet (SDS / MSDS) is available for this product to support laboratory handling, storage, and safety assessment.
Certificates of Analysis are batch-specific. Please contact us to request a COA, and we will provide it by email.
Frequently Asked Questions
Which specification should I quote when ordering tyrosine with a free phenol?
Specify Fmoc-Tyr-OH, AS2056, CAS 92954-90-0, and the required quantity. The catalog pack sizes are 100 g, 500 g, and 1 kg. This is the >99% purity, phenol-unprotected derivative; select the protected alternative when the route requires O-tBu protection.
Can Fmoc-Tyr-OH directly replace Fmoc-Tyr(tBu)-OH?
Not without reviewing the route. The free phenol in Fmoc-Tyr-OH changes which functional groups are exposed during coupling and modification steps.
Does Fmoc-Tyr-OH already contain a phosphate group?
No. It contains an unmodified phenolic hydroxyl; phosphorylation is a separate chemical transformation.
Research Use Only
For research use only. Not for human or veterinary use.