22209-85-4

Upstream product

• 2133-40-6 L-proline methyl ester monohydrochloride 
• 102988-93-2 C₁₆H₂₁NO₆ 
• 4132-86-9 N-benzyloxycarbonylalanine 
• 26607-51-2 N-benzyloxycarbonyl-D-alanine 
• 501-53-1 benzyl chloroformate 
• 139373-72-1 (S)-1-{2-[(Z)-Hydroxyimino]-propionyl}-pyrrolidine-2-carboxylic acid methyl ester 

Downstream Products

• 36357-32-1 (3S,8aS)-3-methylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione 
• 129474-02-8 Cbz-D-Ala-L-Pro-NH₂ 
• 36238-64-9 (3R,8aS)-3-Methyl-1,2,3,4,6,7,8,8a-octahydropyrrolo<1,2-a>pyrazine-1,4-dione 
• 99764-63-3 Leu-Ser-p-nitro-Phe-Nle-Ala-Leu-OMe*TFA 

Relevant academic research and scientific papers

Design, synthesis, and application of enantioselective coupling reagent with a traceless chiral auxiliary

(Chemical Equation Presented) Stable chiral N-triazinylbrucinium tetrafluoroborate enantioselectively activates racemic carboxylic acids yielding enantiomerically enriched amides, esters, and dipeptides with er from 8:92 to 0.5:99.5. Due to the departure

Synthesis of fused 1,2,5-triazepine-1,5-diones and some N2- and N3-substituted derivatives: Potential conformational mimetics for cis-peptidyl prolinamides

The synthesis of a new fused 1,2,5-triazepine-1,5-dione heterocycle, which is expected to mimic structural features of cis-peptldyl prolinamides, is described. The required parent heterocycle, corresponding to cis-glycy-(2S)-prolinamide, has been prepared in good yield by the cyclisation of N-(2-bromoacetylprolyl)-hydrazine which is itself generated in situ from the bromoacetyl proline methyl ester. Analogues corresponding to cis-(2R)-alanyl- and cis-(2S)-alanyl-(2S)-prolinamide have been similarly prepared from the appropriate N-(2-bromopropionyl)proline methyl esters and hydrazine hydrate where the cyclisation step, involving the displacement of bromide, has been shown to occur with inversion of configuration at C-2 of the propionyl moiety. Acylation at the N-3 position of the triazepine is equivalent to N-terminal acylation of the residue preceding the proline residue in cis-aminoacyl prolinamides. This has been achieved without incident using standard peptide coupling procedures. Extension at the 'C-terminal' has been achieved by preparing elaborated hydrazine precursors which are reacted with suitably activated esters of N-α-halogenoacylprolines, prior to cyclisation, to give the required fused triazepine dione. Thus it is possible to prepare constrained cis-peptidyl prolyl peptide mimetics of defined stereochemistry based upon this new triazepine dione in which all of the non-proline residues can be varied.

A Novel Method for Preparation of Optically Active Dipeptide. Chemo- and Stereoselective Reduction of 2-Hydroxyimino Amides with Samarium Diiodide

Various α,β-unsaturated amides derived from α-amino acids are converted to the corresponding 2-hydroxyimino amides of α-amino acids by the reaction with butyl nitrite and silane, which are directly reduced with samarium diiodide to the optically active di