Regio- and Stereoselective Lipase-Catalysed Acylation of Methyl alpha-D-Glycopyranosides with Fluorinated beta-Lactams
: Sundell Riku, Siirola Elina, Kanerva Liisa T
Publisher: Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
: 2014
: European Journal of Organic Chemistry
: EurJOC
: 2014
: 30
: 6753
: 6760
: 8
: 1434-193X
DOI: https://doi.org/10.1002/ejoc.201402800
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 of the gluco- and mannopyranosides and the high reactivity of the pyridylazetidinone restricted product formation. Activation of the β-lactam ring by the presence of fluorine substituents was shown to be necessary for the enzymatic acylation reaction. The (S)-enantiomers of the racemic β-lactam substrates reacted with the sugars.