Fmoc-D-methionine sulfoxide

Fmoc-D-methionine sulfoxide is an Fmoc-protected D-amino acid derivative in which the methionine side chain is oxidized to a sulfoxide, retaining a stereogenic center at the alpha-carbon while introducing a highly polarizable S=O functionality. The molecule combines an N-(9H-fluoren-9-ylmethoxycarbonyl) protecting group with a free carboxylate (typically present as a protected acid form depending on the supplier specification) that participates in standard peptide coupling chemistry. The sulfoxide can influence conformational preferences and side-chain reactivity, enabling controlled oxidation-state handling during peptide assembly and downstream transformations. The chiral sulfoxide and the D-configuration make it suitable for stereochemically defined amino acid and peptidomimetic construction where oxidation-state fidelity and side-chain polarity are relevant.

1. Peptide Synthesis

Fmoc-D-methionine sulfoxide is used as a protected amino acid building block for solid-phase peptide synthesis and related automated peptide assembly workflows. The Fmoc group supports base-mediated N-deprotection, while the carboxyl functionality enables amide bond formation under peptide coupling conditions, allowing incorporation of the D-methionine sulfoxide residue into peptide sequences. The side-chain sulfoxide provides a polar, oxidation-state-defined handle that can affect local hydrogen-bonding patterns and methionine oxidation mimicry in peptide analogs. The resulting sulfoxide-containing peptides can be generated for structure-defined studies, including peptide fragment preparation and stereochemically controlled peptide library synthesis.

2. Peptidomimetics And SAR

Fmoc-D-methionine sulfoxide supports peptidomimetic construction for structure-activity relationship studies where methionine oxidation state and side-chain polarity are treated as explicit structural variables. The D-amino acid stereochemistry enables access to enantiomerically defined analogs, while the sulfoxide moiety can serve as a stable surrogate for oxidized methionine in biomolecular recognition studies. The Fmoc-protected scaffold allows sequential assembly into constrained or functionalized peptide-like frameworks, including cyclic precursors and side-chain modified analogs. Downstream, sulfoxide-bearing peptide mimetics can be converted into further derivatives for SAR mapping, fragment screening, and conformational probing within amino acid chemistry research.

3. Chemical Biology Labeling

Fmoc-D-methionine sulfoxide is applicable to chemical biology workflows that require oxidation-state-aware side-chain functionality for biomolecule modification strategies. The sulfoxide group can participate in selective chemistries that depend on oxidation state, enabling controlled conversion to other sulfur oxidation patterns or serving as a recognition element in engineered peptide probes. The Fmoc-protected amino acid format facilitates incorporation into targeting peptides, affinity ligands, or enzyme-reactive sequences using standard peptide coupling logic. The resulting labeled or functionalized constructs can be used to interrogate binding interfaces, trafficking motifs, or protein interaction surfaces with stereochemically defined residues.

4. Protein Engineering

Fmoc-D-methionine sulfoxide is suitable for protein engineering and synthetic protein segment design where non-natural D-amino acid residues and oxidation-state-defined side chains are incorporated into peptide domains. The protected amino acid format enables stepwise assembly of D-residue-containing sequences that can be used as building blocks for larger constructs, including modular domains and protease-resistant peptide scaffolds. The sulfoxide functionality can be leveraged to tune polarity and local electrostatics relative to unoxidized methionine, supporting studies of how sulfur oxidation influences folding propensity and interaction geometry. The ability to generate stereochemically consistent sequences makes it useful for constructing defined variants for biochemical investigation and applied protein-material design.

5. Process Chemistry Intermediate

Fmoc-D-methionine sulfoxide is employed as a controlled chiral intermediate in process chemistry and fine chemical synthesis for manufacturing routes that require Fmoc-protected amino acid inputs. The Fmoc group provides a robust N-protection strategy compatible with common peptide-coupling and deprotection sequences, supporting scalable preparation of sulfoxide-containing peptide building blocks and downstream intermediates. The sulfoxide side chain introduces a functional group that can be carried through synthetic steps with oxidation-state control, enabling later conversion to other sulfur-containing motifs when required by the target synthesis plan. The compound's defined stereochemistry and protected functionality support reproducible intermediate generation for industrial peptide manufacturing and specialty chemical production where chiral amino acid derivatives are processed in batch or continuous workflows.

1. Effect of Probiotic Lactobacillus plantarum on Streptococcus mutans and Candida albicans Clinical Isolates from Children with Early Childhood Caries

2. The spatiotemporal control of signalling and trafficking of the GLP-1R

3. Relatedness of antibodies to peptides containing homocitrulline or citrulline in patients with rheumatoid arthritis

4. TMEM16F and dynamins control expansive plasma membrane reservoirs

5. Novel Peptide-Based PD1 Immunomodulators Demonstrate Efficacy in Infectious Disease Vaccines and Therapeutics