97512-83-9

Upstream product

• 134469-02-6 S-nitroso-L-cysteine 
• 873-55-2 sodium benzenesulfonate 
• 98-09-9 benzenesulfonyl chloride 
• 52-90-4 L-Cysteine 
• 52-89-1 l-cysteine hydrochloride 

Downstream Products

• 13081-14-6 N⁵-((R)-3-(((R)-2-amino-2-carboxyethyl)disulfanyl)-1-((carboxymethyl)amino)-1-oxopropan-2-yl)-L-glutamine 
• 102837-27-4 S-Phenylsulphonyl-N-acetyl-L-cysteine 
• 18840-45-4 L-Cystein-D-penicillamin-disulfid 

Relevant academic research and scientific papers

SOME OBSERVATION CONCERNING THE S-NITROSO AND S-PHENYLSULPHONYL DERIVATIES OF L-CYSTEINE AND GLUTATHIONE

The preparation of the thiolsulphonate derivatives 3 and 7 of L-cysteine and glutathione, respectively, via their corresponding S-nitroso derivatives 2 and 6, is described.

Diazotization of S-Sulfonyl-cysteines

We report the preparation of enantiomerically enriched β-thio-α-hydroxy and α-chloro carboxylic acid and ester building blocks by diazotization of S-sulfonyl-cysteines. The thiosulfonate protecting group demonstrated resistance to oxidation and attenuation of sulfur's nucleophilicity by the anomeric effect. The key transformation was optimized by a 22 factorial design of experiment, highlighting the unique reactivity of cysteine derivatives in comparison with aliphatic amino acids.

Exploring new activating groups for reactive cysteine NCAs

Due to its ability to reversibly crosslink proteins, cysteine has a unique role as an amino acid in nature. For controlled, asymmetric formation of disulfides from two thiols, one thiol needs to be activated. While few activating groups for cysteine have been proposed, they are usually not stable against amines making them unsuitable for solid phase peptide synthesis or amine initiated polymerization of α-amino acid-N-carboxy-anhydrides (NCAs). In this Letter we describe a series of new thiol activated cysteines, as well as their NCAs and explore the link between electron deficiency of the leaving group and control over NCA polymerization.

Conversion of S-phenylsulfonylcysteine residues to mixed disulfides at pH 4.0: Utility in protein thiol blocking and in protein-S-nitrosothiol detection

A three step protocol for protein S-nitrosothiol conversion to fluorescent mixed disulfides with purified proteins, referred to as the thiosulfonate switch, is explored which involves: (1) thiol blocking at pH 4.0 using S-phenylsulfonylcysteine (SPSC); (2) trapping of protein S-nitrosothiols as their S-phenylsulfonylcysteines employing sodium benzenesulfinate; and (3) tagging the protein thiosulfonate with a fluorescent rhodamine based probe bearing a reactive thiol (Rhod-SH), which forms a mixed disulfide between the probe and the formerly S-nitrosated cysteine residue. S-Nitrosated bovine serum albumin and the S-nitrosated C-terminally truncated form of AdhR-SH (alcohol dehydrogenase regulator) designated as AdhR-SNO were selectively labelled by the thiosulfonate switch both individually and in protein mixtures containing free thiols. This protocol features the facile reaction of thiols with S-phenylsulfonylcysteines forming mixed disulfides at mild acidic pH (pH = 4.0) in both the initial blocking step as well as in the conversion of protein-S-sulfonylcysteines to form stable fluorescent disulfides. Labelling was monitored by TOF-MS and gel electrophoresis. Proteolysis and peptide analysis of the resulting digest identified the cysteine residues containing mixed disulfides bearing the fluorescent probe, Rhod-SH.