N-(9-Fluorenylmethoxycarbonyloxy)succinimide
[CAS# 82911-69-1]

Identification

• Classification: Biochemical >> Amino acids and their derivatives >> Other protected amino acids
• Name: N-(9-Fluorenylmethoxycarbonyloxy)succinimide
• Synonyms: Fmoc-ONSu; Fmoc-OSu; 9-Fluorenylmethyl-succinimidyl-carbonate; N-(9H-Fluoren-2-ylmethoxycarbonyloxy)succinimide; Fmoc N-hydroxysuccinimide ester
• Molecular Formula: C₁₉H₁₅NO₅
• Molecular Weight: 337.33
• CAS Registry Number: 82911-69-1
• EC Number: 433-520-5
• SMILES: C1CC(=O)N(C1=O)OC(=O)OCC2C3=CC=CC=C3C4=CC=CC=C24

Properties

• Solubility: 1 mmole (2 ml DMF)
• Melting point: 150-153 °C

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H302-H317-H411
• Safety Statements: P261-P264-P270-P272-P273-P280-P301+P317-P302+P352-P321-P330-P333+P317-P362+P364-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	4	H302

Discovery and Applications

N-(9-Fluorenylmethoxycarbonyloxy)succinimide, commonly abbreviated as FMOC-succinimide, is a chemical compound widely used in the field of organic synthesis, particularly in peptide chemistry. This substance is characterized by the presence of a 9-fluorenylmethoxycarbonyl (FMOC) group attached to a succinimide moiety. The FMOC group is a protecting group used to shield amino acids during peptide synthesis, facilitating the formation of complex peptide sequences.

The discovery of FMOC-succinimide is linked to the development of protective group strategies in peptide synthesis. The FMOC group was introduced as a solution to the challenge of selectively protecting amino acids while allowing for the efficient formation of peptide bonds. FMOC-succinimide serves as a valuable reagent for introducing the FMOC protecting group to amino acids, which can later be selectively deprotected to yield the final peptide product.

One of the primary applications of FMOC-succinimide is in solid-phase peptide synthesis (SPPS), a widely used method for constructing peptides in a stepwise fashion. During SPPS, amino acids are sequentially added to a growing peptide chain attached to a solid support. The FMOC group is used to protect the amino group of each amino acid, preventing unwanted reactions and ensuring the correct sequence of amino acids. After each coupling step, the FMOC group is removed to expose the amino group for the next coupling reaction. This strategy enhances the efficiency and specificity of peptide synthesis, making it possible to produce a wide range of peptides for research and therapeutic applications.

In addition to peptide synthesis, FMOC-succinimide is employed in the synthesis of other organic molecules where selective protection of functional groups is required. Its use extends to various chemical processes where the FMOC group provides stability and reactivity control, facilitating the formation of complex organic structures.

The versatility of FMOC-succinimide makes it a key tool in organic synthesis and peptide chemistry. Its development has significantly advanced the field of peptide synthesis, enabling the production of a diverse array of peptides with high purity and accuracy.

References

1987. Improved purities for Fmoc‐amino acids from Fmoc‐ONSu. International Journal of Peptide and Protein Research, 30(3).
DOI: 10.1111/j.1399-3011.1987.tb03351.x

2020. Synthesis of Pyrrolidinyl PNA and Its Site-Specific Labeling at Internal Positions by Click Chemistry. Methods in molecular biology (Clifton, N.J.).
DOI: 10.1007/978-1-0716-0243-0_3

2023. Enhanced hexamerization of insulin via assembly pathway rerouting revealed by single particle studies. Communications Biology, 6(1).
DOI: 10.1038/s42003-022-04386-6