66675-21-6

Upstream product

• 100-44-7 benzyl chloride 
• 1499-46-3 L-Histidine methyl ester 
• 98-88-4 benzoyl chloride 
• 4467-54-3 l-histidine methyl ester dihydrochloride 
• 125281-44-9 C₂₈H₂₅N₃O₆ 
• 64-17-5 ethanol 

Downstream Products

• 6298-07-3 α,δ-dibenzoyl-γ-oxoornithine methyl ester 
• 125281-46-1 methyl (2S,4R)-2,4,5-tribenzamidopentanoate 
• 125281-47-2 methyl (2S,4S)-2,4,5-tribenzamidopentanoate 
• 125281-46-1 methyl (2S,4R)/(2S,4S)-2,4,5-tribenzamidopentanoate 

Relevant academic research and scientific papers

Cysteine as a sustainable sulfur reagent for the protecting-group-free synthesis of sulfur-containing amino acids: Biomimetic synthesis of l-ergothioneine in water

Biomass-derived cysteine was used as a sustainable sulfur source for the synthesis of rare sulfur-containing amino acids, such as l-ergothioneine (4), which might be a new vitamin, and various l- or d-2-thiohistidine compounds. Key in this simple, one-pot two-step procedure in water is a bromine-induced regioselective introduction of cysteine followed by a novel thermal cleavage reaction in the presence of thiols, a safer alternative to hazardous red phosphorus. Besides avoiding hazardous sulfur reagents, the new protecting-group-free approach reduces drastically the total number of steps, compared to described procedures. The main drawback, i.e. handling of liquid bromine as an activating and oxidizing reagent in water, was addressed by evaluating four alternative methods using in situ generation of bromine or HOBr, and first encouraging results are described.

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.

Approach to Chiral Vicinal Diacylamines by Bamberger Ring Cleavage of Substituted Imidazoles

Ring cleavage of ethyl 3-propanoate (1) with (-)-menthyl chloroformate introduces chiral carbamate substituents on the double bond which, upon hydrogenation, induces preferred formation of ethyl (4S)-4,5-bispentanoate (5) (5:1 ratio of diastereomers).The ring cleavage benzoylation product of (S)-histidine methyl ester, with a chiral center in the side chain, gives rise to (2S,4R)/(2S,4S)-2,4,5-tribenzamidopentanoates (13, 14), in 2:1 ratio upon hydrogenation.