244221-77-0Relevant articles and documents
Enantioselective Resolution Copolymerization of Racemic Epoxides and Anhydrides: Efficient Approach for Stereoregular Polyesters and Chiral Epoxides
Li, Jie,Ren, Bai-Hao,Wan, Zhao-Qian,Chen, Shi-Yu,Liu, Ye,Ren, Wei-Min,Lu, Xiao-Bing
supporting information, p. 8937 - 8942 (2019/06/11)
Herein we report an efficient strategy for preparing isotactic polyesters and chiral epoxides via enantioselective resolution copolymerization of racemic terminal epoxides with anhydrides, mediated by enantiopure bimetallic complexes in conjunction with a nucleophilic cocatalyst. The chirality of both the axial linker and the diamine backbones of the ligand are responsible for the chiral induction of this kinetic resolution copolymerization process. The catalyst systems exhibit exceptional levels of enantioselectivity with a kinetic resolution coefficient exceeding 300 for various racemic epoxides, affording highly isotactic copolymers (selectivity factors of more than 300) with a completely alternating structure and low polydispersity index. Most of the produced isotactic polyesters are typical semicrystalline materials with melting temperatures in the range from 77 to 160 °C.
Asymmetric reduction of 1-(benzoazol-2-ylsulfanyl)propan-2-ones using whole cells of Mortierella isabellina, Debaryomyces hansenii, Geotrichum candidum and Zygosaccharomyces rouxii
Borowiecki, Pawel,Wloczewska, Malgorzata,Ochal, Zbigniew
, p. 9 - 16 (2015/01/09)
Growing cells of four fungal strains were used in reduction of 1-(benzoazol-2-ylsulfanyl)propan-2-ones3a-c to corresponding (R)-(+)-1-(benzoazol-2-ylsulfanyl)propan-2-ols (R)-(+)-4a-c. All of the investi-gated yeast strains displayed a very high activity toward prochiral ketones 3a-c converting them tothe desired alcohols after relatively short reaction time (1-3.5 h). The biotransformation products wereisolated with moderate to good yields (45-89%) and in highly enantioenriched forms (94-99% ee). Ste-reoselective bioreduction of 1-(1H-benzimidazol-2-ylsulfanyl)propan-2-one 3a by D. hansenii DSM 3428growing cells provided the respective (R)-alcohol with >99% yield, in reasonable 65% isolated yield andin a highly stereoselective manner (98% ee) after 3 h of cultivation. In the same culture, bioreduction of1-(1,3-benzoxazol-2-ylsulfanyl)propan-2-one 3b led to a 76% yield, 65% isolated yield and very high 94%ee of the formed (R)-alcohol. Similar 1.5 h incubation of 1-(1,3-benzothiazol-2-ylsulfanyl)propan-2-one3c in G. candidum LOCK 105 culture resulted in the corresponding (R)-alcohol preparation in moderate45% isolated yield with excellent enantiomeric purity (99% ee).
Lipase-catalyzed kinetic resolution of 1-(1,3-benzothiazol-2-ylsulfanyl) propan-2-ol with antifungal activity: A comparative study of transesterification versus hydrolysis
Borowiecki, Pawe?,Fabisiak, Marcin,Ochal, Zbigniew
, p. 4597 - 4602 (2013/06/27)
A study of chemoenzymatic synthesis of both enantiomers of 1-(1,3-benzothiazol-2-ylsulfanyl)propan-2-ol was carried out. Several commercially available lipase preparations were tested as biocatalysts in the kinetic resolution process of target compound by enantioselective transesterification and/or hydrolysis. CAL-B (Novozym 435) was found to be the optimal catalyst. The lipase-mediated hydrolysis approach appeared to be superior to the transesterification reaction. Absolute configuration of the obtained alcohol was postulated, applying modified Mosher's methodology. The inhibitory activity of the synthesized benzothiazole derivatives against pathogenic fungi was checked.
