129866-71-3Relevant academic research and scientific papers
Dynamic kinetic resolution of α-chloro β-keto esters and phosphonates: Hemisynthesis of Taxotere through Ru-DIFLUORPHOS asymmetric hydrogenation
Prevost, Sebastien,Gauthier, Sebastien,De Andrade, Maria Cristina Cano,Mordant, Celine,Touati, Ali Rhida,Lesot, Philippe,Savignac, Philippe,Ayad, Tahar,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie,Genet, Jean-Pierre
experimental part, p. 1436 - 1446 (2010/11/03)
The dynamic kinetic resolution (DKR) of racemic α-chloro β-ketoesters and α-chloro β-ketophosphonates through ruthenium-mediated asymmetric hydrogenation is reported. The corresponding α-chloro β-hydroxyesters and α-chloro β- hydroxyphosphonates were obtained in good to high enantio- and diastereomeric excesses using, in particular, the atropisomeric ligand DIFLUORPHOS. This methodology allowed an efficient preparation of the anti phenylisoserine side chain of Taxotere which has been used for the hemisynthesis of the cancer therapeutic agent itself. In addition, 13C NMR in chiral oriented solvents was used to investigate the DKR effect.
Chemoenzymatic synthesis of the C-13 side chain of paclitaxel (Taxol) and docetaxel (Taxotere)
Hamamoto, Hiromi,Mamedov, Vakhid A.,Kitamoto, Makiko,Hayashi, Nobuyuki,Tsuboi, Sadao
, p. 4485 - 4497 (2007/10/03)
Reduction of methyl 3-chloro-2-oxo-3-phenylpropanoate with various reducing agents gave syn- and anti-3-chloro-2-hydroxy-3-phenylpropanoates 3, which underwent an efficient lipase-catalyzed resolution. All four diastereomers were subsequently converted to N-benzoyl-(2R,3S)-3-phenylisoserine methyl ester, C-13 side chain analogues of paclitaxel (Taxol).
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.
Synthesis of all four homochiral stereoisomers of methyl 3-phenyl-1H-aziridine-2-carboxylate
Thijs, Lambertus,Orskamp Jos,Adriaan,Marielle,Eenstra, Rolf W.,Legters, Johan,Zwanenburg, Binne
, p. 2611 - 2622 (2007/10/02)
Sodium -E3-phenylglycidate (±)-2E was prepared using the Darzens' procedure. Classical resolution with 1-phenylethylamine afforded optically pure salts (+)-(2S,3R)-2E and (-)-(2R,3S)-2E. Alternatively, (±)-2E was converted into (±)-2Z by ring opening of ethyl ester (±)1E with hydrogen bromide, followed by recyclization and saponification. Classical resolution of (±)-2Z with ephedrine afforded optically pure salts (+)-(2S,3S)-2Z and (-)-(2R,3R)-2Z Treatment of the four sodium salts with sodium azide followed by esterification gave hydroxy azido esters 3, which were finally converted into the four homochiral stereoisomers of methyl 3-phenyl-1H-aziridine-2-carboxylate 5 in a reaction with triphenylphosphine and subsequent heating of the initially formed oxazaphospholidines 4.
