An unusual diepoxyguaianolide from Stevia tomentosa

作者：Valdez Calderon Alejandro; Martin Torres Valencia J; Jesus Manriquez Torres J; Velazquez Jimenez Rene; Roman Marin Luisa U; Hernandez Hernandez Juan D; Cerda Garcia Rojas Carlos M; Joseph Nathan Pedro

来源：Tetrahedron Letters, 2013, 54(25): 3286-3289.

DOI：10.1016/j.tetlet.2013.04.056

• Absolute configuration
• 1,5:3,4-Diepoxyguaianolide
• Vibrational circular dichroism
• X-ray diffraction

The aerial parts of Stevia tomentosa afforded a new guaianolide which was characterized by physical and spectroscopic data as (-)-1,5:3,4-diepoxyguaia-10(14)-en-12,8-olide (1). The absolute configuration of this unusual compound containing two beta-oriented epoxide groups in the five-membered carbocyclic ring, one located at the C-1 and C-5 ring junction, was established as (1S,3S,4S,5R,7R,8R,11S)-1 by vibrational circular dichroism spectroscopy in combination with density functional theory calculations, and by evaluation of Flack and Hooft X-ray parameters.

• 出版日期2013-6-19