Abstract
An asymmetric formal synthesis of azadirachtin, a potent insect antifeedant, was accomplished in 30 steps to Ley's synthetic intermediate (longest linear sequence). The synthesis features: 1) rapid access to the optically active right-hand segment starting from the known 5-hydroxymethyl-2-cyclopentenone scaffold; 2) construction of the B and E rings by a key intramolecular tandem radical cyclization; 3) formation of the hemiacetal moiety in the C ring through the α-oxidation of the six-membered lactone followed by methanolysis. The asymmetric formal synthesis of azadirachtin (1) was accomplished by utilizing the tandem radical cyclization reaction as a key step. The route to the key intermediate 2 requires the longest linear sequence of 30 steps.
Original language | English |
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Pages (from-to) | 14920-14923 |
Number of pages | 4 |
Journal | Angewandte Chemie - International Edition |
Volume | 54 |
Issue number | 49 |
DOIs | |
Publication status | Published - 2015 Dec 1 |
Externally published | Yes |
Keywords
- acetals
- cyclizations
- natural products
- radicals
- stereoselectivity
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)