Planta Med 2014; 80 - PN1
DOI: 10.1055/s-0034-1382683

Computationally assisted assignment of highly strained isochromene nucleus

MM Ghoneim 1, 4, KM Elokely 3, AA El-Hela 4, AEI Mohammad 4, SJ Cutler 3, RJ Doerksen 3, SA Ross 1, 2
  • 1National Center for Natural Products Research
  • 2Department of Pharmacognosy
  • 3Department of Medicinal Chemistry, School of Pharmacy, The University of Mississippi, University, MS 38677, USA
  • 4Department of Pharmacognosy, Faculty of Pharmacy, University of Al-Azhar, Cairo 11371, Egypt

Assignment of the absolute configuration of highly strained isochromene from Asphodelus microcarpus using a combination of molecular modeling and spectroscopic data. The R and S isomers were sketched in maestro 2D sketcher, converted to 3D structures and minimized using OPLS2005 force field and charges with extended cutoffs of 8.0 Å for Van der Waals, 20.0 Å for Electrostatic and 4.0 Å for H-bond.

Fig. 1: Gaussian 09 PM3 optimized structure showing all bond lengths