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.
Chemical Fingerprinting of Conifer Needle Essential Oils and Solvent Extracts by Ultrahigh-Resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
Extractives are an important class of compounds in plants because they contribute to many of their physicochemical properties such as color, odor, density, strength, permeability, and hygroscopicity. Moreover, they also possess significant biological activity and are thus an important part of the plants’ defense mechanisms against biotic and abiotic stresses. Tree needles are a rich source of extractives, counting for as much as 40% of their dry weight. In this study, chemical fingerprinting of essential oils and solvent extracts, obtained from the needles of four conifer tree species (i.e., pine, spruce, larch, and juniper), was performed by using ultrahigh-resolution Fourier transform ion cyclotron mass spectrometry. A wide variety of compounds were detected in the oil samples, including mono-, sesqui-, and diterpenes, terpenoids, fatty and resin acids, esters, and different phenolic compounds. Although the main compounds were present in all the four essential oil samples, large variations in their relative abundances were observed. In contrast, pine needle hexane and toluene extracts showed a high content of resin acids, including pinifolic acid, a rare labdane-type diterpene diacid, and its mono- and dimethyl esters. Thus, by selecting a suitable solvent, specific types of compounds may be isolated from tree needles for further biotechnological or medicinal applications.
Dammaradienyl acetate and taraxasterol from Eupatorium cannabinum: Mass spectrometric study of dammaradienyl acetate and its derivatives
Dammaradienyl acetate (1) (0.01%), taraxasterol (6) (0.0008%) and stigmasterol (c. 0.005%) have been isolated from the whole plant of Eupatorium cannabinum (Compositae). A mass spectrometric study of dammaradienyl acetate (1) and its derivatives has been reported.