Acetyl-L-methionine is an acetylated derivative of the proteinogenic amino acid L-methionine, featuring a thioether-containing methionine side chain and an amino acid backbone. The molecule bears a carboxyl group and an N-acetyl protecting group on the amino functionality, with the stereochemistry corresponding to the L-form indicated in the name. As a protected amino acid derivative, it is used in peptide-related synthesis and in analytical or labeling workflows where blocking the amino group helps control chemoselectivity during coupling or supports preparation of methionine-containing intermediates.
CAT No: CP01504
CAS No:65-82-7
Synonyms/Alias:N-Acetyl-L-methionine;65-82-7;N-Acetylmethionine;Acetyl-L-methionine;Ac-Met-OH;Acetylmethionine;L-(N-Acetyl)methionine;Acetylmethionin;Methionamine;Thiomedon;AcMet;(S)-2-acetamido-4-(methylthio)butanoicacid;Methionine,N-acetyl-,L-;N-Ac-Met;Nalpha-acetyl-L-methionine;UNII-9J12WX5B6A;XUYPXLNMDZIRQH-LURJTMIESA-N;Methionine,N-acetyl-,L-(8CI);MFCD00064441;SBB006737;N-Acetyl(methyl)homocysteine;(2S)-2-acetamido-4-(methylsulfanyl)butanoicacid;l-n-acetyl-Methionine;N-ACETYL-METHIONINE;N-acetyl-S-methylhomocysteine
Acetyl-L-methionine is an acetylated derivative of L-methionine in which the amino group is converted to an acetamide, leaving the thioether-containing methionine side chain intact. This neutral, more chemically stable form is frequently used where an N-acylated amino acid is required for peptide-related intermediate work, controlled reactivity, or as a defined chemical reference material in analytical studies. Its L-configuration and sulfur-containing side chain make it a practical building block when methionine's stereochemistry must be preserved while the α-amino functionality is masked.
1. Peptide Building Block Use
Acetyl-L-methionine is used in peptide chemistry workflows where an N-acylated methionine unit is needed to control terminal reactivity during intermediate preparation and segment handling. Researchers performing custom peptide synthesis and peptide library development often select this derivative to avoid free amino-group side reactions and to maintain a defined methionine stereochemical identity while the α-nitrogen is already protected as an acetamide. In practice, it supports the preparation of methionine-containing peptide fragments and related N-acylated intermediates that can be carried forward into downstream coupling steps under conditions compatible with acetamide stability.
2. Pharmaceutical Intermediate Development
Acetyl-L-methionine is also applied as a defined, stereochemically consistent amino acid intermediate in medicinal chemistry and specialty chemical manufacturing, particularly when an N-acylated methionine motif is incorporated into larger synthetic targets. Process development teams and synthetic chemistry groups value the masked α-amino functionality for streamlining downstream transformations that require a stable, non-zwitterionic substrate rather than a free amino acid. The thioether side chain provides a chemically distinctive handle for further derivatization strategies in intermediate sequences, while the acetylated nitrogen helps reduce variability associated with free amine reactivity during multi-step synthesis.
3. Analytical Reference And Standards
Acetyl-L-methionine is widely used as an analytical standard and reference material for method development and quality control in laboratories that quantify N-acylated amino acid species. Because the compound has a clear, unambiguous structure (acetylated α-amino group with a methionine thioether side chain), it is commonly included in calibration sets or used to verify retention behavior and detector response in LC-based workflows. Analytical chemists also rely on it to support identification and confirmation of acetylated methionine forms in complex matrices, where distinguishing N-acylated derivatives from free amino acids is essential for accurate profiling.
4. Chemical Biology Substrate Probing
Acetyl-L-methionine is used in chemical biology and biochemical research settings where N-acylated amino acid derivatives are required as substrates or probes to study enzyme processing or to benchmark reactivity under defined conditions. Investigators often choose an acetylated methionine derivative to modulate α-amino accessibility while retaining the methionine side chain, enabling more controlled experimental comparisons than with free L-methionine. In such workflows, the compound serves as a chemically defined reagent for assay development and mechanistic screening at the level of functional group recognition, without introducing additional variability from free amine chemistry.
1. Immune-awakening Saccharomyces-inspired nanocarrier for oral target delivery to lymph and tumors
3. TMEM16F and dynamins control expansive plasma membrane reservoirs
4. C-Peptide replacement therapy and sensory nerve function in type 1 diabetic neuropathy
If you have any peptide synthesis requirement in mind, please do not hesitate to contact us at . We will endeavor to provide highly satisfying products and services.
Creative Peptides is a trusted CDMO partner specializing in high-quality peptide synthesis, conjugation, and manufacturing under strict cGMP compliance. With advanced technology platforms and a team of experienced scientists, we deliver tailored peptide solutions to support drug discovery, clinical development, and cosmetic innovation worldwide.
From custom peptide synthesis to complex peptide-drug conjugates, we provide flexible, end-to-end services designed to accelerate timelines and ensure regulatory excellence. Our commitment to quality, reliability, and innovation has made us a preferred partner across the pharmaceutical, biotechnology, and personal care industries.
Read More