✦ LIBER ✦
NMR assignments and absolute stereochemistry of two guaianolide sesquiterpenes from Tanacetum densume subsp. amani
✍ Scribed by Ayhan Ulubelen; Nezhun Gören; Tian-Yi Jiang; Lincoln Scott; Manoelson Tianasoa-Ramomojy; John M. K. Snyder
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 429 KB
- Volume
- 33
- Category
- Article
- ISSN
- 0749-1581
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The guaianolide sesquiterpene pyrethroidinin (1) and the corresponding ketone parishin A (2) wee isolated from Tanacetum densum subsp. amani (Asteraceae). The absolute stereochemistry of 1 was established as (1__R__, 3__R__, 6__S__, 7__S__, 10__R__) on the basis of the differential shielfing in the ^1^H NMR spectra of the (−)‐ and (+)‐O‐methylmandelate esters. The structure, including absolute stereochemistry, of 2 was confirmed by oxidation of 1 whit Jones' reagent.