Chemoenzymatic preparation of fluorine-substituted β-lactam enantiomers exploiting Burkholderia cepacia lipase
摘要:
Both enantiomers of fluorinated and non-fluorinated 4-phenyl-2-azetidinones are prepared in high enantiopurities (ee 99%) by a chemoenzymatic method, using a double resolution technique to N-hydroxymethylated beta-lactams in the presence of Burkholderia cepacia lipase as the source of enantiopurity. N-Deprotections yield the beta-lactam enantiomers from the corresponding hydroxymethylated counterparts using KMnO4 in a mixture of acetone and water. (c) 2007 Elsevier Ltd. All rights reserved.
Regio- and Stereoselective Lipase-Catalysed Acylation of Methyl α-<scp>D</scp>-Glycopyranosides with Fluorinated β-Lactams
作者:Riku Sundell、Elina Siirola、Liisa T. Kanerva
DOI:10.1002/ejoc.201402800
日期:2014.10
Burkholderia cepacia lipase (lipase PS-D) catalysed acylation with 3,3-difluoro-4-phenyl-, -thiophen-3-yl- and -4-pyridylazetidin-2-ones was examined for the formation of N-Boc-protected 6-O-acylated sugar–β-amino acid conjugates from methyl α-D-galacto-, -gluco- and mannopyranosides and Boc2O. The 6-O-acylated glycopyranoside–β-amino acid conjugates were isolated and characterized. The low solubility
Burkholderia cepacia lipase and activated β-lactams in β-dipeptide and β-amino amide synthesis
作者:Xiang-Guo Li、Maria Lähitie、Liisa T. Kanerva
DOI:10.1016/j.tetasy.2008.07.017
日期:2008.8
The work describes fluorine-activated and N-Boc-activated beta-lactams as acyl donors to N-nucleophiles in the presence of Burkholderia cepacia lipase (lipase PS-D). Fluorine activation at the beta-lactam ring causes the ring to open in high enantioselectivity and allows the preparation of beta-dipeptides and beta-amino amides. in the case of N-Boc-activation, the chemical ring opening is significant. beta-Dipeptide formation can then be considerably enhanced by the presence of lipase PS-D and/or by temperature. (C) 2008 Elsevier Ltd. All rights reserved.
Enantioselective acylation of alcohols with fluorinated β-phenyl-β-lactams in the presence of Burkholderia cepacia lipase
作者:Xiang-Guo Li、Maria Lähitie、Mari Päiviö、Liisa T. Kanerva
DOI:10.1016/j.tetasy.2007.06.033
日期:2007.7
the acylation of alcohols with 3,3-difluoro-4-phenylazetidin-2-one rac-1, trans-3-fluoro-4-phenylazetidin-2-one rac-2 and 4-phenylazetidin-2-one rac-3 in the presence of immobilized lipase PS from Burkholderia cepacia in dry tert-butyl methyl ether (TBME). Fluorine activation in the compounds studied was essential in order to split the β-lactam ring with lipase PS. The highly enantioselective ring
Chemoenzymatic preparation of fluorine-substituted β-lactam enantiomers exploiting Burkholderia cepacia lipase
作者:Xiang-Guo Li、Liisa T. Kanerva
DOI:10.1016/j.tetasy.2007.10.003
日期:2007.10
Both enantiomers of fluorinated and non-fluorinated 4-phenyl-2-azetidinones are prepared in high enantiopurities (ee 99%) by a chemoenzymatic method, using a double resolution technique to N-hydroxymethylated beta-lactams in the presence of Burkholderia cepacia lipase as the source of enantiopurity. N-Deprotections yield the beta-lactam enantiomers from the corresponding hydroxymethylated counterparts using KMnO4 in a mixture of acetone and water. (c) 2007 Elsevier Ltd. All rights reserved.