A study of the properties and13C NMR spectra of pinifolic acid and its derivatives
The properties and13C NMR spectra of pinifolic acid (13S-labd-8,17-ene-15,18-dioic acid), its monomethyl ester, its dimethyl ester, its dicyclohexylammonium salt, dihydropinifolic acid, 18-hydroxy-13S-labd-8(17)-en-15-oic acid, the cyclohexylammonium salt of the monomethyl ester, the bis(diethylammonium) salt, pinifodiol (13S-labd-8(17)-ene-15,18-diol), the acetate of 18-hydroxy-13S-labd-8(17)-en-15-oic acid, and the diacetate of pinifodiol have been studied.
Five new labdane diterpene oxides from Eupatorium jhanii
The authors would like to thank Dr. A. Morales, University of Merida (Venezuela) for gathering the plant and for the sustained interest he has shown in the progress of this work.
Dihydroflavonols and other flavonoids of Eupatorium species
Abstract Chloroform extracts of a hybrid of Eupatorium capillifolium (Lam.) Small and E. perfoliatum L. yielded the dihydroflavonols (2R, 3R)-7-methoxy-3,5,4′-trihydroxyflavanone (IIa), (2R, 3R)-3,4′-dihydroxy-5,7-dimethoxyflavanone (IIIa) and either (2R, 3R)-3,7-dimethoxy-3,5,4′-trihydroxy- or (2R, 3R)-7,4′-dimethoxy-3,5,3′-trihydroxyflavanone (Ia or Ic). Ia (or Ic) and IIIa are new; the stereochemistry of IIa has not been assigned previously. Genkwanin and quercetin 3-methyl ether were also found. E. capillifolium gave IIIa and IIa. E. perfoliatum gave no crystalline flavone fractions.