145475-56-5Relevant 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.
Highly Enantioselective Reduction of 3-Chloro-2-oxoalkanoates with Fermenting Bakers' Yeast. A New Synthesis of Optically Active 3-Chloro-2-hydroxyalkanoates and Glycidic Esters
Tsuboi, Sadao,Furutani, Hiroyuki,Ansari, Mohammad Hafeez,Sakai, Takashi,Utaka, Masanori,Takeda, Akira
, p. 486 - 492 (2007/10/02)
Reduction of 3-chloro-2-oxoalkanoic esters with fermenting bakers' yeast gave optically active 3-chloro-2-hydroxyalkanoic esters 2 (anti(2S,3R)/syn(2S,3S) = 52:48-90:10) in 50-85percent yields with > 95percent ee except for 43percent ee of ethyl syn-(2S,3S)-3-chloro-2-hydroxy-4-phenylbutanoate (2j).Compounds 2 were treated with NaOEt to give (E)-(2R,3S)-2,3-epoxyalkanoates 3 in 30-66percent yields with 44-64percent ee.Optically active 2,3-epoxy alcohols (cis-23, trans-23, and trans-25), key intermediates for the syntheses of (-)-disparlure (4), mosquito pheromone (5), and a component of passion fruit flavor (6), were prepared with more than 86percent ee in high yields.
