α-Me-Gly(Propargyl)-OH (CAS 1231709-27-5) corresponds to (S)-2-amino-2-methylpent-4-ynoic acid, a noncanonical amino acid that combines α-methyl substitution with a terminal alkyne side chain.

The alkyne provides a compact chemical-biology handle for azide-alkyne cycloaddition after suitable protection and incorporation, while α-methylation increases steric substitution at the backbone center. This combination can support both conjugation and conformational design in the same residue.

Product Information

Terminal Alkyne as a Click-Chemistry Handle

The propargyl side chain terminates in an alkyne, which can participate in copper-catalyzed azide-alkyne cycloaddition (CuAAC) and other alkyne-selective transformations under compatible conditions. It can therefore be used to install labels, linkers, affinity tags, or other azide-bearing components after the amino acid has been incorporated into a protected intermediate or peptide.

The product contains an alkyne, not an azide. Reaction planning should preserve the alkyne through any earlier protection/coupling steps.

α-Methylation Adds a Second Design Variable

The α-methyl substituent increases steric demand and can reduce conventional backbone flexibility. In sequence design, this means the residue is not simply a propargylglycine surrogate: its conformational behavior may differ because the backbone center is more substituted.

For additional side-chain-functionalized residues, explore our noncanonical building block range.

Protection and Incorporation Planning

The supplied molecule has free amino and carboxyl groups, so controlled peptide incorporation usually requires an appropriate N-protection strategy first. The terminal alkyne should also be evaluated for compatibility with coupling, deprotection, metal catalysts, and any sulfur-containing components in the final workflow.

For full-sequence projects using clickable residues, modified peptide synthesis can be planned around both incorporation and downstream conjugation.

Product Documents

MSDS - α-Me-Gly(Propargyl)-OH (AS2123)

The Safety Data Sheet provides product identification, hazard information, handling and storage guidance, exposure controls, transport information, and regulatory information for laboratory use.

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 the side-chain handle an alkyne or an azide?

It is a terminal alkyne. The exact identity associated with CAS 1231709-27-5 is (S)-2-amino-2-methylpent-4-ynoic acid.

Can it be used for click chemistry?

The terminal alkyne can support azide-alkyne cycloaddition under compatible reaction conditions.

Is this amino acid already Fmoc-protected?

No. The amino and carboxyl groups are unprotected in the listed product, so protection is typically required before controlled peptide incorporation.

Research Use Only.