Two drimane lactones,valdiviolide and 11‐epivaldiviolide,in the form of a 1:1 cocrystal obtained from Drimys winteri extracts

A cocrystal, C₁₅H₂₂O₃·C₁₅H₂₂O₃, (I), obtained from Drimys winteri, is composed of two isomeric drimane sesquiterpene lactones, namely valdiviolide, (Ia), and 11‐epivaldiviolide, (Ib), neither of which has been reported in the crystal form. Both diastereoisomers present three chiral centres at sites 5, 10 and 11, with an SSR sequence in (Ia) and an SSS sequence in (Ib). O—H...O hydrogen bonds bind molecules into chains running along [20] and the chains are in turn linked by π–π stacking interactions to define planar weakly interacting arrays parallel to (001).     

Four New Compounds from Sinacalia tangutica

Four new compounds, 9α‐hydroxy‐1β‐methoxycaryolanol ( 1 ), stigmast‐5‐ene‐7α,22α‐diol‐3β‐tetradecanoate ( 2 ), 7‐O‐(6′‐acetoxy‐β‐D ‐glucopyranosyl)coumarin ( 3 ), and 8‐O‐(6′‐acetoxy‐β‐D ‐glucopyranosyl)‐7‐hydroxycoumarin ( 4 ), together with ten known compounds, were isolated from the aerial parts of Sinacalia tangutica. The structures of the new compounds were established by means of extensive spectroscopic analyses (1D‐ and 2D‐NMR, EI‐MS, HR‐ESI‐MS, as well as IR and UV) and by comparison of their spectroscopic data with those of structurally related compounds reported in the literature.     

(E)-2,6,10-Trimethyldodec-8-en-2-ol: An Undescribed Sesquiterpenoid from Copaiba Oil

The use of copaiba oil has been reported since the 16th century in Amazon traditional medicine, especially as an anti-inflammatory ingredient and for wound healing. The use of copaiba oil continues today, and it is sold in various parts of the world, including the United States. Copaiba oil contains mainly sesquiterpenes, bioactive compounds that are popular for their positive effect on human health. As part of our ongoing research endeavors to identify the chemical constituents of broadly consumed herbal supplements or their adulterants, copaiba oil was investigated. In this regard, copaiba oil was subjected to repeated silica gel column chromatography to purify the compounds. As a result, one new and seven known sesquiterpenes/sesquiterpenoids were isolated and identified from the copaiba oil. The new compound was elucidated as (E)-2,6,10-trimethyldodec-8-en-2-ol. Structure elucidation was achieved by 1D- and 2D NMR and GC/Q-ToF mass spectral data analyses. The isolated chemical constituents in this study could be used as chemical markers to evaluate the safety or quality of copaiba oil.     

A new eremophilane-type sesquiterpene from Ligularia virgaurea

A new eremophilane-type sesquiterpene,1α,8β,10β-trihydroxy-6β-(2-methylacryloyl)oxyeremophil-7(11)-en-8α,12-olide, was isolated from the roots of Ligularia virgaurea.Its structure was established on the basis of various spectroscopic analyses, including the 1D,2D NMR techniques and HR-ESI-MS.