Abstract
The reduction of cyclic Mannich ketones having antibacterial activity showed poor stereoselectivity with L-Selectride®, sodium trimethoxyborohydride and diisobutylaluminium hydride, while lithium aluminium hydride and, in particular, sodium borohydride often yielded a single stereoisomer. The size of the ring strongly influenced the stereocomposition of the reaction mixtures. An increased preference for the trans isomer was attributed to a weak intramolecular hydrogen bond between the OH and the N, as demonstrated by X-ray crystallography. After reduction, the antibacterial activity of the product decreased dramatically ("S-form") but was not completely abolished in deep rough mutants of Gram-negative bacteria.
Original language | English |
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Pages (from-to) | 34-52 |
Number of pages | 19 |
Journal | Arkivoc |
Volume | 2004 |
Issue number | 7 |
State | Published - 1 Jan 2004 |
Keywords
- Deep rough (Re) mutants
- Molecular modelling
- NMR spectroscopy
- Reduction
- X-ray crystallography