Jf. Hu et al., ASSIGNMENT OF THE H-1 AND C-13 NMR-SPECTRA OF LUDOVICIN-B BY 2-DIMENSIONAL NMR TECHNIQUES, Bulletin des Societes chimiques belges, 106(3), 1997, pp. 141-146
Ludovicin B(I) was isolated firstly from Artemisia mongolica Fisch as
an eudesmanolide. Analysis of H-1 and C-13 NMR spectra of Ludovicin B(
I), with the aid of various 2D NMR techniques (H-1-H-1 COSY, HMQC, HMB
C) and NOE difference spectra, has allowed unambiguous chemical shift
assignments of all the protons and carbons.