23926-51-4Relevant academic research and scientific papers
Stereochemistry and conformation of skyllamycin, a non-ribosomally synthesized peptide from streptomyces sp. Acta 2897
Schubert, Vivien,Di Meo, Florent,Saaidi, Pierre-Loic,Bartoschek, Stefan,Fiedler, Hans-Peter,Trouillas, Patrick,Suessmuth, Roderich D.
, p. 4948 - 4955 (2014/05/06)
Skyllamycin is a non-ribosomally synthesized cyclic depsipeptide from Streptomyces sp. Acta 2897 that inhibits PDGF-signaling. The peptide scaffold contains an N-terminal cinnamoyl moiety, a β-methylation of aspartic acid, three β-hydroxylated amino acids and one rarely occurring α-hydroxy glycine. With the exception of α-hydroxy glycine, the stereochemistry of the amino acids was assigned by comparison to synthetic reference amino acids applying chiral GC-MS and Marfey-HPLC analysis. The stereochemistry of α-hydroxy glycine, which is unstable under basic and acidic conditions, was determined by conformational analysis, employing a combination of data from NOESY-NMR spectroscopy, simulated annealing and free MD simulations. The simulation procedures were applied for both R- and S-configured α-hydroxy glycine of the skyllamycin structure and compared to the NOESY data. Both methods, simulated annealing and free MD simulations independently support S-configured α-hydroxy glycine thus enabling the assignment of all stereocenters in the structure of skyllamycin and devising the role of two-component flavin dependent monooxygenase (Sky39) as S-selective.
Efficient preparation of biologically important 1,2-amino alcohols
Gupta, Pankaj,Rouf, Abdul,Shah, Bhahwal A.,Mukherjee, Debaraj,Taneja, Subhash C.
, p. 505 - 519 (2013/01/15)
An efficient three-step methodology developed for the preparation of 1,2-amino alcohols. In the first step a rapid coupling between bromoketones and potassium phthalimide in ionic liquid produced-phthalimido ketones in quantitative yields, which is followed by a facile reduction using NaCNBH 3 in acetic acid to give corresponding phthalimido alcohols and finally effecting hydrazinolysis in water at 60C to yield biologically important 1,2-amino alcohols.
Total synthesis of the amino hip analogue of didemnin A
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, (2008/06/13)
Disclosed is a synthetic method for the preparation of analogs of Didemnin A (1), particularly the Amino-Hip analog of Didemnin A, also known as “AipDidemnin A” (8). These compounds have the following structures:
ENANTIOSPECIFIC AND DIASTEREOSELECTIVE SYNTHESIS OF ANTI α-HYDRAZINO- AND α-AMINO-β-HYDROXYACIDS THROUGH "ELECTROPHILIC AMINATION" OF β-HYDROXYESTERS
Guanti, Giuseppe,Banfi, Luca,Narisano, Enrica
, p. 5553 - 5562 (2007/10/02)
β-Hydroxyesters 1a-d were transformed into corresponding dianions and condensed with di-t-butylazodicarboxylate to give anti protected α-hydrazino-β-hydroxyesters 2a-d with good diastereoselectivities (up to 94:6).Cleavage of protecting groups followed by ester hydrolysis gave the previously unknown anti α-hydrazino-β-hydroxyacids 4a-d, which were in turn converted by hydrogenolysis into anti α-amino-β-hydroxyacids 5a-d.Starting from (S) 1a, enantiomerically pure (2S,3S) allo-threonine 5a was obtained in good overall yields.On the contrary, reaction of silyl ketene acetal 10, derived from 1a, with a diazonium salt furnished predominantly the syn isomer, but in unsatisfactory yield.
ENANTIOSELECTIVE HYDROLYSIS BY BAKER'S YEAST - II. ESTERS OF N-ACETYL AMINO ACIDS
Glaenzer, B. I.,Faber, K.,Griengl, H.
, p. 771 - 778 (2007/10/02)
D-N-Acetyl amino acid esters were obtained via enantioselective hydrolysis of their racemates by use of fermenting yeast.Evidence is given that proteinases are the enzymes involved.
