Fmoc-β-Ala-Gly-OH is a preassembled beta-alanine-glycine dipeptide with an Fmoc-protected amino terminus and free C-terminal carboxylic acid. Unlike an alpha-alanine residue, beta-alanine contains an additional methylene group between the amino and carboxyl functions and has no alpha stereocenter.

This extra backbone spacing makes Fmoc-β-Ala-Gly-OH useful for flexible peptide spacers, linker engineering, bioconjugation and beta-amino-acid-containing peptide design. It can introduce a defined beta-Ala-Gly segment without building the two residues separately.

Product Information

Why Beta-Alanine Changes Backbone Spacing

Beta-alanine places one additional methylene unit in the backbone compared with alpha-alanine. This changes the distance and conformational freedom between neighboring functional groups without introducing a side-chain stereocenter.

When combined with glycine, the result is a compact but flexible beta-Ala-Gly spacer that can be used to separate a peptide from a label, lipid, linker, chelator or other functional group.

Applications in Peptide Linker Design

Potential uses include peptide-conjugate spacers, fluorescent or biotin linker synthesis, ADC/PDC research intermediates, beta-peptide-inspired constructs, flexible linker optimization and preparation of modified peptide fragments.

Final constructs can be evaluated in binding, uptake, imaging, cleavage, stability or other in vitro assays according to the attached functional group and project design.

Fmoc-β-Ala-Gly-OH vs Fmoc-β-Ala-OH

Fmoc-β-Ala-OH is the single beta-alanine building block. Fmoc-β-Ala-Gly-OH is a preassembled dipeptide containing an additional glycine residue and therefore introduces a longer predefined spacer in one coupling step.

Purchasing and QC Considerations

Confirm beta-Ala-Gly sequence identity, Fmoc protection and lot-specific purity by COA and appropriate analytical data.

Product Documents

A Material Safety Data Sheet (MSDS) is available for this product to support laboratory handling, storage and safety assessment.

MSDS_Fmoc-beta-Ala-Gly-OH_AS4073

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 the difference between beta-alanine and alanine?

Beta-alanine contains an additional methylene in the amino-acid backbone and lacks the alpha stereocenter present in L- or D-alanine.

Why use a beta-Ala-Gly spacer?

It provides flexible spacing with minimal side-chain bulk and can separate a peptide from an attached functional group.

What is the CAS number of Fmoc-beta-Ala-Gly-OH?

Public database records support CAS 133368-47-5 for this molecular identity.

Related Technical Resources

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