6695-43-8

Upstream product

• 16874-17-2 L-phenylalanine tert-butyl ester 
• 3401-36-3 (N-benzyloxycarbonyl)-L-alanine N-hydroxysuccinimide ester 
• 2768-53-8 N-benzyloxycarbonyl-L-alanyl-L-phenylalanine 
• 75-65-0 tert-butyl alcohol 
• 159390-24-6 2-tert-Butyl-1,3-bis-(2,2-dimethyl-[1,3]dioxolan-4-ylmethyl)-isourea 
• 1142-20-7 N-Cbz-Ala 
• 3235-14-1 (S)-2-((S)-2-Benzyloxycarbonylamino-propionylamino)-3-phenyl-propionic acid methyl ester 
• 7524-50-7 methyl (2S)-2-amino-3-phenylpropanoate hydrochloride 
• 1161-13-3 N-Cbz-L-Phe 
• 16881-34-8 N-benzyloxycarbonyl-L-phenylalanine t-butyl ester 
• 28819-05-8 (S)-2-benzyloxycarbonylamino-propionic acid methyl ester 
• 15100-75-1 L-phenylalanine tert-butyl ester hydrochloride 
• 203640-41-9 Z-L-Ala 2,2,2-trifluoroethyl ester 

Downstream Products

• 3235-14-1 (S)-2-((S)-2-Benzyloxycarbonylamino-propionylamino)-3-phenyl-propionic acid methyl ester 
• 103338-25-6 (S)-tert-butyl 2-((S)-2-aminopropanamido)-3-phenylpropanoate 
• 1268383-59-0 N-{3-[([2-(2,3-difluorophenyl)-5H-imidazo[4,5-d]pyridazin-5-yl]{3-[4-(propyloxy)-2-(trifluoromethyl)phenyl]-5-isoxazolyl}acetyl)oxy]propanoyl}-L-alanyl-L-phenylalanine 
• 2768-53-8 N-benzyloxycarbonyl-L-alanyl-L-phenylalanine 

Relevant academic research and scientific papers

Enzymatic synthesis of activated esters and their subsequent use in enzyme-based peptide synthesis

Chemoenzymatic peptide synthesis is potentially the most cost-efficient technology for the synthesis of short and medium-sized peptides. However, there are still some limitations when challenging peptides, e.g. containing sterically demanding acyl donors, non-proteinogenic amino acids or proline residues, are to be synthesized. To remedy these limitations, special ester moieties have been used that are specifically recognized by the enzyme, e.g. guanidinophenyl, carboxamidomethyl (Cam) or trifluoroethyl (Tfe) esters, which, unfortunately, are notoriously difficult to synthesize chemically. Herein, we demonstrate that Cam and Tfe esters are very useful for Alcalase-CLEA mediated peptide synthesis using sterically demanding and non-proteinogenic acyl donors as well as poor nucleophiles, and combinations thereof. Furthermore, these esters can be efficiently synthesized by using the lipase Cal-B or Alcalase-CLEA. Finally, it is shown that the ester synthesis by Cal-B and subsequent peptide synthesis by Alcalase-CLEA can be performed simultaneously using a two-enzyme-one-pot approach with glycolamide or 2,2,2-trifluoroethanol as additive.

Imidazopyridazine Compounds for Treating Viral Infections

Disclosed are compounds and compositions of Formula (I), pharmaceutically acceptable salts and solvates thereof, and their preparation and uses for treating viral infections mediated at least in part by a virus in the Flaviviridae family of viruses:

Fully enzymatic peptide synthesis using C-terminal tert-butyl ester interconversion

Chemoenzymatic peptide synthesis is potentially the most cost-efficient technology for the synthesis of short and medium-sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required an

ISOPROPENYL CHLOROCARBONATE (IPCC) IN AMINO ACID AND PEPTIDE CHEMISTRY: ESTERIFICATION OF N-PROTECTED AMINO ACIDS; APPLICATION TO THE SYNTHESIS OF THE DEPSIPEPTIDE VALINOMYCIN

Esterification of N-protected α-amino acids was achieved via isopropenyl chlorocarbonate (IPCC) activation.In situ alcoholysis of the unstable mixed anhydride intermediate was catalised by 4-(dimethylamino)pyridine (DMAP).Competing isopropenyl ester formation was negligible when using methylene chloride as the solvent.A variety of esters from primary and secondary alcohols were obtained with good yields (60 to 90 percent), and even the more hindered tertiobutyl alcohol gave acceptable yields under more drastic conditions.The improvement in depsipeptide synthetic methodology is illustrated by preparation of the antibiotic valinomycin, using IPCC for ester bond formation, and BOP reagent for peptide coupling and the last-step cyclisation.