Structural elucidation of a new triquinane sesquiterpenoid, presilphiperfolane-7α,8α-diol, , isolated from , was accomplished by combining solvent-induced removal of chemical shift degeneracy and computational (DFT-GIAO) prediction of NMR spectra with the analysis of H NMR splitting patterns. In addition to extensive NMR experiments (in 10 different solvents), MS, and FTIR, the identity of was also confirmed by chemical transformations. The applied approach can facilitate structural elucidation of organic molecules and decrease the probability of an erroneous identification, permitting an unambiguous stereochemical elucidation and full NMR assignment. The pharmacological/toxicological profile of was evaluated in several different models.
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