$40.00 - $1848.00
Fmoc-Sar-OH (CAS 77128-70-2) is an N-methylated protected amino-acid building block used in backbone N-methylated peptide and peptidomimetic synthesis. Its main synthetic value is backbone N-methylation, conformational tuning and proteolytic-stability/SAR studies.
N-methylation increases steric demand during coupling; reagent choice and coupling time may need adjustment relative to the unmethylated residue. For reproducible work, confirm identity and protection state against the COA before transferring conditions from a related analog.
Product Information
| Product Name | Fmoc-Sar-OH |
| Catalog No. | AS4279 |
| CAS No. | 77128-70-2 |
| Molecular Formula | C18H17NO4 |
| Molecular Weight | 311.33 g/mol |
| Compound Type | N-methylated protected amino-acid building block |
| Primary Research Use | Backbone N-methylated peptide and peptidomimetic synthesis |
Backbone N-Methylation
Fmoc-Sar-OH introduces an N-methylated amino-acid unit into peptide or peptidomimetic synthesis. Backbone N-methylation removes an amide hydrogen after incorporation and can alter local conformation, hydrogen bonding and proteolytic susceptibility.
Coupling Considerations
N-methylated residues are more sterically demanding than their unmethylated analogs. Difficult couplings may require stronger activation, longer reaction time or sequence-specific optimization rather than simple reagent excess.
Selection in SAR Programs
Use the exact N-methylglycine building block and protection state required by the synthesis. N-methylation and side-chain changes should be treated as separate variables when interpreting conformational or activity effects.
Related options are grouped under unusual amino acid range. For broader route support, see advanced peptide building blocks.
Product Documents
The Safety Data Sheet provides product identification, hazard information, handling and storage guidance, exposure controls, transport information, and regulatory information for laboratory use.
Certificates of Analysis (COAs) are batch-specific. Please contact us to request the COA for your product, and we will provide it by email.
Frequently Asked Questions
What does N-methylation change in Fmoc-Sar-OH?
It removes a backbone amide hydrogen after incorporation and can alter local hydrogen bonding, conformation and proteolytic susceptibility.
Can Fmoc-Sar-OH be more difficult to couple?
Yes. Its N-methylated backbone nitrogen is more sterically demanding than the corresponding unmethylated residue, so activation and reaction time may need sequence-specific adjustment.