869012-75-9Relevant academic research and scientific papers
Asymmetric bioreduction of ethyl 3-halo-2-oxo-4-phenylbutanoate by Saccharomyces cerevisiae immobilized in Ca-alginate beads with double gel layer
Milagre, Humberto M. S.,Milagre, Cintia D. F.,Moran, Paulo J. S.,Santana, Maria Helena A.,Rodrigues, J. Augusto R.
, p. 611 - 617 (2012/12/22)
The asymmetric bioreduction of ethyl 3-halo-2-oxo-4-phenylbutanoate was studied for several microorganisms and especially for Saccharomyces cerevisiae. The highest chemical yield (90%), de (70%) and ee (96-99%) were obtained with S. cerevisiae immobilized in calcium alginate beads with double gel layers, and reaction conditions were optimized by changing matrix of immobilization, concentration of substrate, and feeding with glucose as electron donor. The entrapment of cells with double gel layers was fundamental to achieve high enantio- and diastereoselectivity.
A highly enantioselective chemoenzymatic synthesis of syn-3-amino-2-hydroxy esters: Key intermediates for taxol side chain and phenylnorstatine
Rodrigues, J. Augusto R.,Milagre, Humberto M. S.,Milagre, Cintia D. F.,Moran, Paulo J. S.
, p. 3099 - 3106 (2007/10/03)
Starting from the bromination of α-ketoesters to obtain 3-bromo-2-oxoalkanoates and bioreduction with Saccharomyces cerevisiae entrapped in calcium alginate pellets with double gel layers, syn-(2R,3S)-β-bromo- α-hydroxy esters were obtained regioselectively in high yields and high ee. These chiral bromohydrins were cyclized to epoxides that were transformed into oxazolidines and finally opened by acidic hydrolysis to give syn-(2S,3S)-β-amino-α-hydroxy esters in high overall yields and high ee. The enantiomeric excesses of all the intermediates were maintained during the reaction sequence.
