82518-64-7Relevant academic research and scientific papers
Synthesis of β-Hydroxy α-Amino Acids through Br?nsted Base-Catalyzed syn-Selective Direct Aldol Reaction of Schiff Bases of Glycine o-Nitroanilide
Vera, Silvia,Vázquez, Ana,Rodriguez, Ricardo,Pozo, Sandra Del,Urruzuno, I?aki,de Cózar, Abel,Mielgo, Antonia,Palomo, Claudio
, p. 7757 - 7772 (2021)
Here we report the highly enantio- and syn-selective synthesis of β-hydroxy α-amino acids from glycine imine derivatives under Br?nsted base (BB) catalysis. The key of this approach is the use of benzophenone-derived imine of glycine o-nitroanilide as a pronucleophile, where the o-nitroanilide framework provides an efficient hydrogen-bonding platform that accounts for nucleophile reactivity and diastereoselectivity.
Characterisation of the aminopeptidase from non-germinated winter rape (Brassica napus L.) seeds
Kania, Joanna,Gillner, Danuta M.
, p. 180 - 186 (2016/04/19)
Rapeseed plays a crucial role in food and fuel industry. Since aminopeptidases take part in many physiological processes in all organisms, it is important to learn their role and characteristics in economically relevant plants. Extracts of non-germinated winter rape seeds were screened for aminopeptidase activity. Substrate specificity, the influence of pH and temperature, as well as effect of protease inhibitors and chosen metal ions on the aminopeptidase activity were determined. The approximate molecular weight estimated by NATIVE-PAGE and SDS-PAGE electrophoresis was ～60 kDa. The partially purified enzyme as well as the aminopeptidases present in crude extract cleaved preferentially Phe-pNA. The activity profiles toward several substrates were also determined. Maximum activity was observed at pH 6.5 and temperature of 40 °C for Phe-pNA as a substrate. Two visible picks in the pH profile toward Phe-pNA, together with other results (IEF) suggest the presence of more than one aminopeptidase, having similar molecular mass. Much lower activity and broad pH profiles were observed for Leu- and Ala-pNA as substrates.
A convenient synthesis of amino acid p-nitroanilides; synthons in the synthesis of protease substrates
Rijkers, Dirk T. S.,Adams, Hans P. H. M.,Hemker, H. Coenraad,Tesser, Godefridus I.
, p. 11235 - 11250 (2007/10/02)
A method is described for the synthesis of N(α)-protected bi- and trifunctional amino acid p-nitroanilides. The reaction uses phosphorus oxychloride as the condensing agent. The synthesis is simple, rapid, free of racemization and affords yields between 70-90%. The synthesis can be performed not only with amino acid derivatives of the urethane type including acid-labile (Z, Boc) and base-labile (Fmoc, Msc) N(α)-protective functions or allyl-derived protections, but also with N(α)-trityl amino acids, albeit in lower yield. The reaction runs in pyridine and its mechanism implies carboxyl activation by formation of a mixed anhydride with phosphorodichloridic acid (HOPOCl2).
Selective Reactions of Azide-Substituted α-Diazo Amides with Olefins and Alcohols Using Rhodium(II) Catalysts
Jeganathan, Alwarsamy,Richardson, Steward K.,Mani, Rajarathnam S.,Haley, Boyd E.,Watt, David S.
, p. 5362 - 5367 (2007/10/02)
The synthesis and addition of azide-substituted α-diazo amides such as N-(4-azidophenyl)-α-diazoacetamide and N-(4-azido-2-hydroxyphenyl)-α-diazoacetamide to olefins and alcohols using either rhodium(II) acetate or preferably rhodium(II) pivalate provided cyclopropanecarboxamides and α-alkoxy amides, respectively, without disrupting the azide functionality.These azide-bearing α-diazo amides are potentially useful in the preparation of photoaffinity cross-linking reagents for studying the mechanism of action of natural products.
