Fmoc-Lys(tBuO-C20-γ-Glu(OtBu))-OH is a specialized lysine-derived peptide building block designed for installation of a long-chain C20 diacid lipidation motif through a gamma-glutamyl linker.

This type of side-chain building block is relevant to long-acting peptide design, where fatty diacid attachment can be used to introduce albumin-binding and pharmacokinetic-modifying motifs into a final peptide. It is best viewed as a lipidation intermediate, not as a finished peptide drug or a direct biological assay reagent.

Product Information

Why This Building Block Is Used

Long-chain fatty-acid and fatty-diacid side chains are widely used in peptide engineering to change hydrophobicity, albumin interaction and systemic exposure of the final peptide. A preassembled Fmoc-Lys lipidation building block allows the side-chain architecture to be introduced at a defined lysine position during peptide synthesis instead of constructing the entire lipid motif after chain assembly.

SPPS and Peptide-Lipidation Applications

Potential synthetic applications include long-acting metabolic peptide analogs, incretin-related peptide research, albumin-binding peptide designs, pharmacokinetic optimization studies and preparation of lipidated peptide standards or analog libraries. The final biological effect depends on the complete peptide sequence, lipid architecture and conjugation position.

Identity and Procurement Considerations

The shorthand name “C20DIACID” does not by itself specify every protecting group. For this SKU, the listed formula and molecular weight correspond to a protected C20-diacid/gamma-Glu intermediate. Researchers should therefore match the requested material using product name, formula, molecular weight, analytical data and lot-specific COA rather than relying on an abbreviated side-chain name alone.

No reliable public CAS number was found for the exact formula-defined protected form. Alan Scientific therefore does not recommend assigning a CAS solely by analogy to a related lipidation intermediate.

Downstream Assay Relevance

The building block itself is intended for chemical synthesis. After incorporation, cleavage, deprotection, purification and characterization, the resulting lipidated peptide may be evaluated in receptor-binding assays, cell-signaling assays, serum-stability studies, albumin-binding studies, pharmacokinetic experiments or in vivo research where appropriate.

Product Documents

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

MSDS_Fmoc-Lys-gamma-glu-C20DIACID_AS4144

Frequently Asked Questions

Is this the fully deprotected C20 diacid?

The listed C₅₄H₈₃N₃O₁₀ formula is consistent with a tert-butyl-protected gamma-Glu/C20-diacid intermediate used for peptide synthesis, not the fully deprotected lipid side chain.

Is this a tirzepatide side-chain building block?

It is structurally related to C20-diacid/gamma-Glu lipidation chemistry used in long-acting incretin research, but it should not be described as the complete tirzepatide side chain because other spacer architectures can be present in the final drug.

What should be checked before ordering?

Confirm molecular formula, molecular weight, protecting-group pattern, requested purity, quantity and lot-specific analytical documentation. These details are more reliable than an abbreviated lipid-side-chain name alone.

Related Technical Resources

Browse Specialty Peptide Building Blocks or discuss sequence-specific lipidated peptide production through our Chemical Peptide Synthesis service.

Research Use Only.