H-D-Cys(Mob)-OH is a deuterated, protected cysteine derivative bearing a thiol-containing side chain and an amino acid backbone with a carboxylic acid group, where Mob denotes a thiol-protecting group attached to the cysteine sulfur. The molecule contains an N-terminal deuterium (H-D) at the amino position and retains the stereochemical relationship implied by the cysteine scaffold, while the side-chain sulfur is masked by the Mob substituent to control chemoselectivity by preventing free thiol reactivity. H-D-Cys(Mob)-OH is used as a protected amino acid building block for cysteine-containing peptide synthesis and for preparing sulfur-functionalized peptide or conjugation intermediates under conditions where selective handling of thiol chemistry is required.
CAT No: CP27235
CAS No:58290-34-9
Synonyms/Alias:3,3',5'-Triiodo-L-thyronine;5817-39-0;3,3',5'-Triiodothyronine;REVERSETRIIODOTHYRONINE;(S)-2-Amino-3-(4-(4-hydroxy-3,5-diiodophenoxy)-3-iodophenyl)propanoicacid;Triiodothyronine,reverse;UNII-8NZ4Y08T96;CHEBI:11684;ReverseT3;L-Tyrosine,O-(4-hydroxy-3,5-diiodophenyl)-3-iodo-;DSSTox_CID_26908;DSSTox_RID_82006;DSSTox_GSID_46908;O-(4-hydroxy-3,5-diiodophenyl)-3-iodo-L-tyrosine;4-(4-hydroxy-3,5-diiodophenoxy)-3-iodo-L-phenylalanine;rT3;CAS-5817-39-0;3,3,5-Triiodothyronine;Isoliothyronine;NCGC00181338-01;ReverseTri-Iodothyronine;ReverseL-triiodothyronine;AC1LD8X0;3',5',3-Triiodothyronine;SCHEMBL93385
H-D-Cys(Mob)-OH is a deuterated, thiol-containing cysteine derivative in which the α-amino group is in the form of an N-protected amino acid (H-D indicates deuterium incorporation at the amino position) and the side-chain sulfur is masked as a Mob group (methoxybenzyl-type thioether protecting group). The molecule retains the amino acid backbone with a free carboxylic acid (-CO2H) and a chiral center at the cysteine α-carbon, providing stereodefined reactivity for peptide coupling and selective deprotection. The Mob-protected thiol is stable under many peptide synthesis conditions yet can be converted to the free thiol under appropriate deprotection strategies, enabling controlled formation of disulfides, thioethers, and thioester-like intermediates. Deuterium labeling can also support mechanistic studies, mass spectrometric tracking, and isotope-resolved characterization of cysteine-containing peptide workflows.
1. Peptide Synthesis
H-D-Cys(Mob)-OH is used in peptide building block preparation where cysteine side-chain protection and stereochemistry are central to chemoselective coupling. The Mob-protected thiol prevents undesired thioether/disulfide formation during standard amide bond construction, while the free carboxylic acid and N-protected amino acid framework support incorporation into peptide chains using peptide coupling chemistry. Deuterium at the amino position can be leveraged for isotope-resolved peptide analysis, including LC-MS identification and fragmentation behavior for cysteine-containing sequences. Downstream deprotection can regenerate the reactive thiol for disulfide bond formation or selective conjugation steps within peptide synthesis programs.
2. Side-Chain Functionalization
H-D-Cys(Mob)-OH is applied to side-chain functionalization workflows that require controlled access to cysteine thiochemistry without premature oxidation. The Mob group functions as a removable protecting group for the sulfur atom, enabling a staged strategy where the protected thioether remains inert during assembly and the thiol is generated later for conjugation chemistries such as alkylation, acylation, or disulfide exchange. The stereodefined cysteine backbone supports predictable reactivity patterns in thiofunctionalization of peptide fragments and amino acid derivatives. Deuterium labeling can further assist in monitoring thiol conversion and tracking cysteine-derived fragments during synthetic optimization and analytical method development.
3. Chemical Biology Labeling
H-D-Cys(Mob)-OH is suitable for chemical biology research requiring cysteine-specific labeling with isotope-enabled readouts. The compound's protected thiol allows incorporation into peptides or small-molecule scaffolds while maintaining compatibility with aqueous or mixed-solvent handling typical of labeling workflows, and subsequent Mob deprotection can expose the thiol for selective capture by electrophilic probes. Deuterium incorporation supports mass-shift discrimination of labeled species, facilitating quantitative comparisons in LC-MS-based studies of labeling efficiency, site occupancy, or reaction kinetics. The amino acid identity and stereochemistry also support biomolecular recognition when cysteine-containing motifs are introduced into peptide mimics used for target engagement studies.
4. Protected Amino Acids
H-D-Cys(Mob)-OH is positioned for protected amino acid chemistry where orthogonal protection of the cysteine side chain is required for multi-step synthesis. The Mob-protected sulfur provides a protection handle that can be managed alongside other protecting-group strategies on peptide or amino acid intermediates, supporting sequential deprotection and controlled functional group unveiling. The free carboxylic acid enables downstream conversion to activated derivatives for coupling or for transformation into peptide-ready formats within synthetic organic chemistry. Deuterium labeling adds an additional structural feature that can be exploited as a tracer in synthetic route development and in isotope-resolved characterization of cysteine-containing products.
5. Process Chemistry Intermediate
H-D-Cys(Mob)-OH serves as a process chemistry intermediate for manufacturing routes that incorporate cysteine residues under protected conditions to control impurity formation. The Mob group's stability during peptide assembly can reduce side reactions associated with free thiols, such as oxidation to disulfides or uncontrolled thioether formation, aligning with scalable peptide synthesis logic. The defined stereochemistry of the cysteine α-center supports consistent product profiles when used as a chiral amino acid input in automated or semi-automated coupling sequences. Deuterium labeling can also be relevant for industrial fine chemical synthesis where isotope-labeled standards or labeled intermediates are required for analytical calibration and quality control of downstream peptide materials.
3. Adipose tissue is a key organ for the beneficial effects of GLP-2 metabolic function
4. Myotropic activity of allatostatins in tenebrionid beetles
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