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Fmoc-Cys(Trt)-OH, also known as Fmoc-protected cysteine with trityl side-chain protection, is a high-purity protected amino acid derivative used in Fmoc-based solid-phase peptide synthesis (SPPS). It features an Fmoc-protected α-amino group and Trt-protected cysteine thiol group, allowing controlled peptide elongation while helping to prevent premature thiol oxidation and unwanted side reactions.
This reagent is especially valuable for the synthesis of cysteine-containing peptides, including peptides requiring disulfide bond formation, cyclic peptide synthesis, bioconjugation, native chemical ligation, and protein engineering applications.
Key Features
| Feature | Details |
|---|---|
| High Purity | ≥99.0% by HPLC for reliable peptide synthesis |
| Fmoc Protection | Protects the α-amino group for controlled Fmoc-SPPS workflows |
| Trt Side-Chain Protection | Protects the cysteine thiol group during peptide elongation |
| High Enantiomeric Purity | ≥99.5% for consistent stereochemical performance |
| Thiol Protection | Helps minimize oxidation and unwanted cysteine side reactions |
| SPPS Compatible | Suitable for cysteine incorporation in linear and cyclic peptides |
| Versatile Research Use | Ideal for peptide synthesis, protein engineering, NCL, and bioconjugation |
Chemical Properties & Identifiers
| Property | Value |
|---|---|
| Product Name | Fmoc-Cys(Trt)-OH, ≥99.0% HPLC |
| CAS Number | 103213-32-7 |
| Empirical Formula | C₃₇H₃₁NO₄S |
| Molecular Weight | 585.71 g/mol |
| MDL Number | MFCD00038538 |
| UNSPSC Code | 12352209 |
| Form | Powder |
| Melting Point | 164–175 °C |
| Assay | ≥99.0% by HPLC |
| Enantiomeric Purity | ≥99.5% |
| Storage Temperature | -20 °C; recommended range -15 °C to -25 °C |
| Solubility | Clearly soluble in DMF; insoluble in water |
| Functional Groups | Fmoc, thiol-protected cysteine, carboxylic acid |
Applications
Fmoc-Cys(Trt)-OH is suitable for:
- Fmoc-based solid-phase peptide synthesis
- Incorporation of cysteine residues into synthetic peptides
- Cysteine-containing peptide synthesis
- Cyclic peptide synthesis
- Disulfide bond-containing peptide preparation
- Native chemical ligation and semi-synthetic protein workflows
- Protein engineering and structural biology research
- Peptide-based pharmaceutical and drug discovery research
- Bioconjugation and thiol-functionalized peptide chemistry
- Proteomics and bioorganic chemistry applications
Coupling Compatibility
Fmoc-Cys(Trt)-OH can be used with multiple peptide coupling strategies, including DIPCDI/HOBt, symmetrical anhydride methods, and uronium or phosphonium-based coupling reagents such as HBTU or PyBOP®. Suitable bases such as collidine may be used in sensitive protocols to help reduce enantiomerization risk.
Ordering Information
| Catalog Number | Quantity |
|---|---|
| 8520080025 | 25 g |
| 8520080100 | 100 g |
| 8520080250 | 250 g |
| 8520080500 | 500 g |
| 8520081000 | 1 kg |
| 8520082000 | 2 kg |
| 8520085000 | 5 kg |
Storage & Handling
Store at -20 °C, preferably between -15 °C and -25 °C, in a dry, tightly sealed container. Protect from moisture, oxidation, and light exposure. Handle in a suitable laboratory environment using appropriate personal protective equipment, including gloves, lab coat, and safety goggles.
Research Use Statement
For Research Use Only (RUO). Not intended for diagnostic or therapeutic use.
Specification: Fmoc-Cys(Trt)-OH
Fmoc-Cys(Trt)-OH, also known as Fmoc-protected cysteine with trityl side-chain protection, is a high-purity protected amino acid derivative used in Fmoc-based solid-phase peptide synthesis (SPPS). It features an Fmoc-protected α-amino group and Trt-protected cysteine thiol group, allowing controlled peptide elongation while helping to prevent premature thiol oxidation and unwanted side reactions.
This reagent is especially valuable for the synthesis of cysteine-containing peptides, including peptides requiring disulfide bond formation, cyclic peptide synthesis, bioconjugation, native chemical ligation, and protein engineering applications.
Key Features
| Feature | Details |
|---|---|
| High Purity | ≥99.0% by HPLC for reliable peptide synthesis |
| Fmoc Protection | Protects the α-amino group for controlled Fmoc-SPPS workflows |
| Trt Side-Chain Protection | Protects the cysteine thiol group during peptide elongation |
| High Enantiomeric Purity | ≥99.5% for consistent stereochemical performance |
| Thiol Protection | Helps minimize oxidation and unwanted cysteine side reactions |
| SPPS Compatible | Suitable for cysteine incorporation in linear and cyclic peptides |
| Versatile Research Use | Ideal for peptide synthesis, protein engineering, NCL, and bioconjugation |
Chemical Properties & Identifiers
| Property | Value |
|---|---|
| Product Name | Fmoc-Cys(Trt)-OH, ≥99.0% HPLC |
| CAS Number | 103213-32-7 |
| Empirical Formula | C₃₇H₃₁NO₄S |
| Molecular Weight | 585.71 g/mol |
| MDL Number | MFCD00038538 |
| UNSPSC Code | 12352209 |
| Form | Powder |
| Melting Point | 164–175 °C |
| Assay | ≥99.0% by HPLC |
| Enantiomeric Purity | ≥99.5% |
| Storage Temperature | -20 °C; recommended range -15 °C to -25 °C |
| Solubility | Clearly soluble in DMF; insoluble in water |
| Functional Groups | Fmoc, thiol-protected cysteine, carboxylic acid |
Applications
Fmoc-Cys(Trt)-OH is suitable for:
- Fmoc-based solid-phase peptide synthesis
- Incorporation of cysteine residues into synthetic peptides
- Cysteine-containing peptide synthesis
- Cyclic peptide synthesis
- Disulfide bond-containing peptide preparation
- Native chemical ligation and semi-synthetic protein workflows
- Protein engineering and structural biology research
- Peptide-based pharmaceutical and drug discovery research
- Bioconjugation and thiol-functionalized peptide chemistry
- Proteomics and bioorganic chemistry applications
Coupling Compatibility
Fmoc-Cys(Trt)-OH can be used with multiple peptide coupling strategies, including DIPCDI/HOBt, symmetrical anhydride methods, and uronium or phosphonium-based coupling reagents such as HBTU or PyBOP®. Suitable bases such as collidine may be used in sensitive protocols to help reduce enantiomerization risk.
Ordering Information
| Catalog Number | Quantity |
|---|---|
| 8520080025 | 25 g |
| 8520080100 | 100 g |
| 8520080250 | 250 g |
| 8520080500 | 500 g |
| 8520081000 | 1 kg |
| 8520082000 | 2 kg |
| 8520085000 | 5 kg |
Storage & Handling
Store at -20 °C, preferably between -15 °C and -25 °C, in a dry, tightly sealed container. Protect from moisture, oxidation, and light exposure. Handle in a suitable laboratory environment using appropriate personal protective equipment, including gloves, lab coat, and safety goggles.
Research Use Statement
For Research Use Only (RUO). Not intended for diagnostic or therapeutic use.
Specification: Fmoc-Cys(Trt)-OH
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Spécifications
| Pack Size | 250g, 1kg, 100g, 500g, 5kg, 2kg, 25g |