Nα-Palmitoyl-(L)-glutamic acid-γ-succinimidyl-α-tert-butyl ester [Pal-Glu(OSu)-OtBu]

Nα-Palmitoyl-(L)-glutamic acid-γ-succinimidyl-α-tert-butyl ester (Pal-Glu(OSu)-OtBu) is a synthetic building block for lipidating peptides, proteins, or other molecules. It contains palmitic acid linked to L-glutamic acid, where the gamma carboxyl is activated as an N-hydroxysuccinimide (NHS) ester (OSu). The alpha carboxyl remains protected by a tert-butyl ester (OtBu), allowing selective deprotection and further modification. The palmitic acid imparts lipophilicity for membrane insertion, while the NHS ester enables conjugation with primary amines.

Appearance

• White to off-white solid, possibly waxy due to the palmitic acid chain.

Source

• Synthetic chemical production, not naturally occurring.

• Available from specialized chemical and bioconjugation suppliers.

Molecular Weight and Structure

• Approximate molecular weight: 566.7 g/mol (C29H50N2O8).

• Structure: Palmitic acid attached to the alpha-amino group of L-glutamic acid, tert-butyl ester protecting the alpha carboxyl, and NHS ester activated gamma carboxyl.

Biological Activity

• Inactive alone; activity depends on conjugated biomolecules.

• Palmitic acid promotes membrane association.

• NHS ester allows conjugation to primary amines; tert-butyl ester enables controlled deprotection.

Purity and Microbial Contamination

• Purity: Typically ≥ 95% by HPLC.

• Minimal microbial contamination; suppliers provide COAs including microbial tests.

Identity and Quality Control

• Confirmed by mass spectrometry, NMR (¹H, ¹³C), and IR spectroscopy.

• Purity assessed by HPLC.

• Optical rotation confirms L-configuration.

• Amine quantification verifies NHS ester reactivity.

• Acid value determination measures free or protected carboxyl groups.

Shelf Life and Storage

Applications

• Lipopeptide synthesis for membrane anchoring.

• Protein lipidation for enhanced membrane interaction.

• Liposomal formulations incorporating lipidated peptides.

• Surface modification with hydrophobic coatings.

• General reagent for bioconjugation via primary amines.

Key Characteristics

• Lipophilic palmitic acid chain enables membrane insertion.

• Reactive NHS ester for amine conjugation.

• Acid-labile tert-butyl ester protects alpha carboxyl group.

• Versatile chemical coupling.

• Soluble in organic solvents: chloroform, dichloromethane, DMSO.

Citation 

• Use keywords “NHS ester lipid protein conjugation” and “OSu ester lipid protein conjugation.”

• Search “palmitic acid protein modification,” “lipopeptide synthesis,” “glutamic acid tert-butyl ester synthesis.”

• Look for articles on “liposomal drug delivery NHS ester lipid” and “self-assembling peptides lipid modification.”

• Supplier technical sheets and chemical databases like Reaxys, SciFinder, PubChem.

• Google Scholar: “NHS ester lipid protein conjugation,” “palmitic acid glutamic acid conjugate,” “liposomal drug delivery NHS ester,” “glutamic acid tert-butyl ester.”