119677-35-9Relevant 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.
Multicomponent catalytic asymmetric aziridination of aldehydes
Gupta, Anil K.,Mukherjee, Munmun,Wulff, William D.
supporting information; experimental part, p. 5866 - 5869 (2011/12/15)
The first multicomponent catalytic asymmetric aziridination reaction is developed to give aziridine-2-carboxylic esters with very high diastereo- and enantioselectivity from aromatic and aliphatic aldehydes. This new method pushes the boundary of the aziridination reaction to substrates that failed with preformed imines.
Addition of azomethine ylides to aldehydes: Mechanistic dichotomy of differentially substituted α-imino esters
Seashore-Ludlow, Brinton,Torssell, Staffan,Somfai, Peter
scheme or table, p. 3927 - 3933 (2010/09/18)
The formal 1,3-dipolar cycloaddition of azomethine ylides and aldehydes is explored, as hydrolysis of the resulting oxazolidine product gives facile access to valuable syn-β-arylβ-hydroxy-α-amino esters. The use of using benzaldehydederived imines as the ylide precursor results in 1,3-dipolar cycloaddition with high conversions but low diastereoselec-tivity. In contrast, the employment of benzophenone-derived imines as the ylide precursor results in an aldol reaction, which gives the intermediate oxazolidine in high diastereoselectivity and requires a weak acid catalyst to achieve higher conversions.
CHEMO-ENZYMATIC SYNTHESIS OF ALL ISOMERIC 3-PHENYLSERINES AND -ISOSERINES
Hoenig, H.,Seufer-Wasserthal, P.,Weber, H.
, p. 3841 - 3850 (2007/10/02)
The synthesis of all isomers of 3-phenylserines and 3-phenylisoserines in enantiomerically pure form is presented.Diastereomerically pure educts (threo/erythro-2-azido-3-butanoyloxy-3-phenyl-propionic esters, threo/erythro-3-azido-2-butanoyloxy-3-phenylpropionic esters, threo-2-butanoylamino-3-butanoyloxy-3-phenylpropionic ester, erythro-3-butanoylamino-2-butanoyloxy-3-phenyl-propionamide) were prepared from cinnamic acid derivatives or via aldol condensations of benzaldehyde and suitable enolates in few steps.These racemates were resolved with lipases from Candida cylindracea (CC) and Pseudomonas fluorescens (P) and the obtained products were hydrogenated to 3-phenylserines and -isoserines.The influence of the acyl group in the enzymatic resolution of erythro-3-azido-2-acyloxy-3-phenylpropionic esters was investigated.
