2002-22-4

Basic information

• Product Name: 2-MERCAPTO-L-HISTIDINE
• Synonyms: L-THIOHISTIDINE;H-HIS(2-MERCAPTO)-OH;H-2-MERCAPTO-HIS-OH;1H-IMIDAZOLE-4-PROPANOIC ACID;2-MERCAPTO-HISTIDINE;2-MERCAPTO-L-HISTIDINE;2-THIOLHISTIDINE;(S)-alpha-amino-2,3-dihydro-2-thioxo-1H-imidazole-4-propionic acid
• CAS NO: 2002-22-4
• Molecular Formula: C₆H₉N₃O₂S
• Molecular Weight: 187.22
• EINECS: 217-899-2
• Product Categories: Amino Acids 13C, 2H, 15N;Amino Acids & Derivatives;Sulfur & Selenium Compounds;Heterocycles
• Mol File: 2002-22-4.mol
• Article Data: 8

Chemical Properties

• Melting Point: 320-325°C
• Boiling Point: 376.3 °C at 760 mmHg
• Flash Point: 181.4 °C
• Appearance: /
• Density: 1.52 g/cm³
• Vapor Pressure: 1.06E-06mmHg at 25°C
• Refractive Index: 1.695
• Storage Temp.: -15°C
• Solubility: Aqueous Acid (Slightly)
• PKA: pK1:1.84(＋1);pK2:8.47(0);pK3:11.4(SH) (25°C)
• CAS DataBase Reference: 2-MERCAPTO-L-HISTIDINE(CAS DataBase Reference)
• NIST Chemistry Reference: 2-MERCAPTO-L-HISTIDINE(2002-22-4)
• EPA Substance Registry System: 2-MERCAPTO-L-HISTIDINE(2002-22-4)

Safety Data

• Hazardous Substances Data: 2002-22-4(Hazardous Substances Data)

Usage

Chemical Properties

Colourless Crystals

Uses

Different sources of media describe the Uses of 2002-22-4 differently. You can refer to the following data:
1. An intermediate in the formation of L-egothioneine, a natural amino acid ubiquitously present in cells and tissues of most plants and mammalian species. In humans, L-ergothioneine is found in red blo od cells, liver, kidney, brain, seminal fluid, and cataract-free lenses at concentrations ranging from 100 uM to 2 mM. L-ergothioneine is exclusively biosynthesized in fungi and mycobacteria. Hence, humans assimilate it through dietary intake.
2. An intermediate in the formation of L-egothioneine, a natural amino acid ubiquitously present in cells and tissues of most plants and mammalian species. In humans, L-ergothioneine is found in red blood cells, liver, kidney, brain, seminal fluid, and cataract-free lenses at concentrations ranging from 100 uM to 2 mM. L-ergothioneine is exclusively biosynthesized in fungi and mycobacteria. Hence, humans assimilate it through dietary intake.L-ergothioneine has been proven to act as an antioxidant in vivo and to afford protection from g and UV radiation as well as from singlet oxygen in vivo. Recently, it has been shown that L-ergothioneine protects isolated perfused heart against the deleterious effect of post-ischemic reperfusion.The intermediate, 2-mercaptohistine has been used for the

InChI:InChI=1/C6H9N3O2S/c7-4(5(10)11)1-3-2-8-6(12)9-3/h2,4H,1,7H2,(H,10,11)(H2,8,9,12)/t4-/m0/s1

Upstream product

• 24424-99-5 di-tert-butyl dicarbonate 
• 4467-54-3 l-histidine methyl ester dihydrochloride 
• 645-35-2 L-histidine monohydrochloride 
• 507-09-5 tiolacetic acid 
• 143673-60-3 benzyl L-2-benzyloxycarbonylamino-4-oxo-5-phthalimidopentanoate 
• 50817-15-7 benzyl L-2-benzyloxycarbonylamino-5-chloro-4-oxopentanoate 
• 50930-59-1 benzyl L-2-benzyloxycarbonylamino-5-diazo-4-oxopentanoate 
• 645-35-2 L-histidine monohydrochloride 
• 540-72-7 sodium thiocyanide 
• 78397-05-4 L-2,5-diamino-4-oxopentanoic acid dihydrochloride 
• 71-00-1 L-histidine 
• 5934-29-2 L-histidine hydrochloride monohydrate 
• 333-20-0 potassium thioacyanate 
• 89765-68-4 C₁₁H₁₇N₃O₄S 

Downstream Products

• 71-00-1 L-histidine 

Relevant articles and documents

Ergothioneine in a peptide: Substitution of histidine with 2-thiohistidine in bioactive peptides

Ergothioneine (EGT) is the betaine of 2-thiohistidine (2-thioHis) and may be the last undiscovered vitamin. EGT cannot be incorporated into a peptide because the α-nitrogen is trimethylated, although this would be advantageous as an EGT-like moiety in a peptide would impart unique antioxidant and metal chelation properties. The amino acid 2-thioHis is an analogue of EGT and can be incorporated into a peptide, although there is only one reported occurrence of this in the literature. A likely reason is the harsh conditions reported for protection of the thione, with similarly harsh conditions used in order to achieve deprotection after synthesis. Here, we report a novel strategy for the incorporation of 2-thioHis into peptides in which we decided to leave the thione unprotected. This decision was based upon the reported low reactivity of EGT with 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB), a very electrophilic disulfide. This strategy was successful, and we report here the synthesis of 2-thioHis analogues of carnosine (βAH), GHK-tripeptide, and HGPLGPL. Each of these peptides contain a histidine (His) residue and possesses biological activity. Our results show that substitution of His with 2-thioHis imparts strong antioxidant, radical scavenging, and copper binding properties to the peptide. Notably, we found that the 2-thioHis analogue of GHK-tripeptide was able to completely quench the hydroxyl and ABTS radicals in our assays, and its antioxidant capacity was significantly greater than would be expected based on the antioxidant capacity of free 2-thioHis. Our work makes possible greater future use of 2-thioHis in peptides.

METHOD FOR THE SYNTHESIS OF 2-THIOHISTIDINE AND THE LIKE

Methods for the synthesis of 2-thiohistidine or a derivative thereof of the formula (I), or of a physiologically acceptable salt, a tautomer, a stereoisomer or a mixture of stereoisomers in any proportions thereof, from a compound of the formula (II) or a physiologically acceptable salt, a tautomer, a stereoisomer or a mixture of stereoisomers in any proportions thereof, by cleavage reaction in the presence of a thiol at a temperature higher than or equal to 60° C. The invention also relates to compounds of the formula (II) and a method for the synthesis thereof.

PROCESS FOR THE SYNTHESIS OF L-(+)-ERGOTHIONEINE

This invention relates to a novel process for the preparation of optically pure L-(+)-ergothioneine. The process for the chemical synthesis of L-ergothioneine comprises steps which consist of reacting L-histidine alkyl ester with an acid halide, chloroformate or pyrocarbonate in the presence of a base, hydrolysis of the alkyl-(S,Z)-2,4,5-triamidopent-4-enoate to obtain a (S)-alkyl 2,5-diamido-4-oxopentanoate, acid catalyzed hydrolysis of the (S)-alkyl 2,5-diamido-4-oxopentanoate followed by reaction with a metal thiocyanate to obtain the thiohistidine, protection of the sulfur of thiohistidine as the tert-butyl thioether, dialkylation of the primary amine to obtain a tertiary amine, quaternization of the tertiary amine, and removal of the protecting group to obtain the desired (S)-3-(2-mercapto-1H-imidazol-5-yl)-2-(trialkylammonio)propanoate (I). This process affords a better yield and is capable of practical application at large scale.