Avermectin-milbemycin studies. 2. An efficient chemical degradation of avermectin b1a
β Scribed by Amos B. Smith III; Andrew S. Thompson
- Publisher
- Elsevier Science
- Year
- 1985
- Tongue
- French
- Weight
- 256 KB
- Volume
- 26
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
β¦ Synopsis
An efficient chemical degradation of avermectin Bla affording intact northern and southern hemispheres has been achieved.
π SIMILAR VOLUMES
gummary -An efficient oxidative degradation of avermectin Bla affording suitably functionalized Cl-C10 and Cll-Czs segments is reported. Recently, we reported a stereospecific total synthesis' of the Cll-C2s segment of the potent anthelmintic agent (+I-avermectin Bla,' culminating in the synthesis
Dianions derived from a variety of 1,3-diketones react with Z-ethyl-3-bromopropenoate to afford unsaturated diketoesters which upon treatment with base undergo facile cyclization-dehydration to p-hydroxybenzoates.
Interesting reactivitics have baen observed upon reaction of epoxy-spiroketal 1 with a variety of dimethyl-aluminum sulfides, and are compared with results obtained upon reaction of the same epoxide 1 with diethyl alu&um cyanide. These chemical modifications provide access to novel avermeuin Bb anal
Absfracfi Avemectin B la A44,4a ,2, has been obtained from avenneztin B la. 1, and its bioactivity evaluated. The key step of the transfommtion is the reduction of an intemxdiate allylic radical with aBu@nH. The avermectins are disaccharide derivatives of a structurally similar group of pentacyclic