101650-08-2

Upstream product

• 67-56-1 methanol 
• 127862-67-3 N-benzyloxycarbonyl-DL-norvaline 2,2,2-trifluoroethyl ester 
• 21691-44-1 Z-L-norvaline 
• 56558-30-6 methyl L-norvalinate hydrochloride 
• 93712-83-5 L-norvaline methyl ester isocyanate 
• 100-51-6 benzyl alcohol 
• 91230-11-4 (1-vinyl-butyl)-carbamic acid benzyl ester 

Downstream Products

• 21691-44-1 Z-L-norvaline 
• 1416992-32-9 C₂₀H₂₇N₃O₅ 
• 1416992-40-9 C₂₀H₂₈N₃O₈S^(1-)*Na⁽¹⁺⁾ 
• 1416992-25-0 C₂₀H₂₉N₃O₅ 
• 1416992-18-1 C₂₁H₂₉N₃O₆ 
• 145842-50-8 benzyl N-[(1S)-1-(hydroxymethyl)butyl]carbamate 

Relevant academic research and scientific papers

2-OXO-1-IMIDAZOLIDINYL IMIDAZOTHIADIAZOLE DERIVATIVES

The present invention relates to 2-oxo-1-imidazolidinyl imidazothiadiazole derivatives, processes for preparing them, pharmaceutical compositions containing them and their use as pharmaceuticals.

Carica papaya lipase catalysed resolution of β-amino esters for the highly enantioselective synthesis of (S)-dapoxetine

An efficient synthesis of the (S)-3-amino-3-phenylpropanoic acid enantiomer has been achieved by Carica papaya lipase (CPL) catalysed enantioselective alcoholysis of the corresponding racemic N-protected 2,2,2-trifluoroethyl esters in an organic solvent. A high enantioselectivity (E > 200) was achieved by two strategies that involved engineering of the substrates and optimization of the reaction conditions. Based on the resolution of a series of amino acids, it was found that the structure of the substrate has a profound effect on the CPL-catalysed resolution. The enantioselectivity and reaction rate were significantly enhanced by switching the conventional methyl ester to an activated trifluoroethyl ester. When considering steric effects, the substituted phenyl and amino groups should not both be large for the CPL-catalysed resolution. The mechanism of the CPL-catalysed enantioselective alcoholoysis of the amino acids is discussed to delineate the substrate requirements for CPL-catalysed resolution. Finally, the reaction was scaled up, and the products were separated and obtained in good yields (≥ 80 %). The (S)-3-amino-3- phenylpropanoic acid obtained was used as a key chiral intermediate in the synthesis of (S)-dapoxetine with very high enantiomeric excess (> 99 %). A carica papaya lipase catalysed resolution of N-protected β-phenylalanine esters has been developed. High enantioselectivity was achieved by two strategies that involved engineering of the substrates and optimization of the reaction conditions. After 50 % conversion, the products were separated and used as key chiral intermediates for the synthesis of (S)-dapoxetine with > 99 % ee. Copyright

Inhibition of norovirus 3CL protease by bisulfite adducts of transition state inhibitors

Noroviruses are the most common cause of acute viral gastroenteritis, accounting for >21 million cases annually in the US alone. Norovirus infections constitute an important health problem for which there are no specific antiviral therapeutics or vaccines. In this study, a series of bisulfite adducts derived from representative transition state inhibitors (dipeptidyl aldehydes and α-ketoamides) was synthesized and shown to exhibit anti-norovirus activity in a cell-based replicon system. The ED 50 of the most effective inhibitor was 60 nM. This study demonstrates for the first time the utilization of bisulfite adducts of transition state inhibitors in the inhibition of norovirus 3C-like protease in vitro and in a cell-based replicon system. The approach described herein can be extended to the synthesis of the bisulfite adducts of other classes of transition state inhibitors of serine and cysteine proteases, such as α-ketoheterocycles and α-ketoesters.

Resolution of non-proteinogenic amino acids via microbial lipase-catalyzed enantioselective transesterification

A number of non-proteinogenic amino acids bearing aliphatic side chains were resolved with moderate to good enantioselectivities (E = 15-42) through the Burkholderia cepacia lipase-catalyzed enantioselective transesterification of the 2,2,2-trifluoroethyl esters of their N-benzyloxycarbonyl derivatives with methanol as a nucleophile in diisopropyl ether.

Resolution of non-protein amino acids via Carica papaya lipase-catalyzed enantioselective transesterification

Carica papaya lipase-catalyzed transesterification of the 2,2,2-trifluoroethyl esters of N-benzyloxycarbonylated dl-amino acids carrying aliphatic side chains proceeded smoothly and, in almost all the cases, enantiospecifically (E = >200), affording the l-methyl esters and leaving the d-trifluoroethyl esters intact.

Asymmetric synthesis of N-protected amino acids by the addition of organolithium carboxyl synthons to ROPHy/SOPHy-derived aldoximes and ketoximes.

A new asymmetric synthesis of alpha-amino acids is described in which the key step is the highly diastereoselective addition of organolithium carboxyl synthons (2-furyllithium, phenyllithium, vinyllithium) to (R)- and (S)-O-(1-phenylbutyl) oximes to give hydroxylamines, with vinyllithium being the most satisfactory nucleophilic reagent. Subsequent reductive cleavage of the N-O bond in hydroxylamines, followed by N-protection, and oxidative cleavage of the carboxyl precursor gave a range of N-protected amino acids and esters. The method was exemplified by the synthesis of a range of derivatives of non-proteinogenic amino acids such as 4-bromophenylalanine, tert-leucine, norvaline, cyclohexyl- and aryl-glycines, 2-amino-8-oxodecanoic acid (Aoda) and alpha-methylvaline.