942057-06-9Relevant academic research and scientific papers
Hetero Diels-Alder synthesis of 3-hydroxypyridines: Access to the nosiheptide core
Lu, Jin-Yong,Arndt, Hans-Dieter
, p. 4205 - 4212 (2008/02/05)
The 1-azadiene hetero Diels-Alder reaction of silylated enol oximes with alkynes was investigated and was optimized to furnish 2,5,6-trisubstituted 3-hydroxypyridines in high yields in one simple operation. Importantly, monosubstituted alkynyl ketones were found to lead to the formation of the 6-isomer with exceptional regioselectivity (>95:5). This methodology was applied to a scaleable synthesis of the core structure of the potent antibiotic nosiheptide. Protecting groups were optimized, which led to a racemization-free seven-step synthesis of the key building block.
