A synthesis of (+)-milbemycin β3. The 3,4-dihydro-2H-pyran approach
Abstract
Nucleophilic scission of oxirane (8) by vinyl alanate (4) and oxirane (11) by metallated 3,4-dihydro-2H-pyran (15) were key steps in the synthesis of (+)-milbemycin β3(1).