Search results for "Terpene"
showing 10 items of 816 documents
Identification of highly effective antitrypanosomal compounds in essential oils from the Apiaceae family
2018
The Apiaceae family encompasses aromatic plants of economic importance employed in foodstuffs, beverages, perfumery, pharmaceuticals and cosmetics. Apiaceae are rich sources of essential oils because of the wealth of secretory structures (ducts and vittae) they are endowed with. The Apiaceae essential oils are available on an industrial level because of the wide cultivation and disposability of the bulky material from which they are extracted as well as their relatively cheap price. In the fight against protozoal infections, essential oils may represent new therapeutic options. In the present work, we focused on a panel of nine Apiaceae species (Siler montamon, Sison amomum, Echinophora spi…
Cinema audiences reproducibly vary the chemical composition of air during films, by broadcasting scene specific emissions on breath
2016
AbstractHuman beings continuously emit chemicals into the air by breath and through the skin. In order to determine whether these emissions vary predictably in response to audiovisual stimuli, we have continuously monitored carbon dioxide and over one hundred volatile organic compounds in a cinema. It was found that many airborne chemicals in cinema air varied distinctively and reproducibly with time for a particular film, even in different screenings to different audiences. Application of scene labels and advanced data mining methods revealed that specific film events, namely “suspense” or “comedy” caused audiences to change their emission of specific chemicals. These event-type synchronou…
Regio- and stereoselective oxyfunctionalization at C-1 and C-5 in sesquiterpene guaianolides
1998
Abstract The regio- and stereoselective functionalization at C-1 and C-5 positions in a guaiane skeleton by allylic hydroxylation are described. The stereochemistry of the resulting compounds are identical to those of the majority of natural 1- and 5-hydroxy-guaianolides.
Novel indole alkaloids from cell suspension cultures of aspidosperma quebracho blanco schlecht
1991
Abstract Two novel monoterpenoid indole alkaloids, aspidochibine ( 1 ) and 3-oxo-14,15-dehydrorhazinilam ( 2 ), were isolated from cell suspension cultures of Aspidosperma quebracho blanco Schlecht. Aspidochibine ( 1 ) exhibits a new alkaloid skeleton. The structure of these alkaloids was elucidated by spectroscopic methods.
Indole Diterpenoids from an Endophytic Penicillium sp.
2019
A chemical investigation of the endophyte Penicillium sp. (strain ZO-R1-1), isolated from roots of the medicinal plant Zingiber officinale, yielded nine new indole diterpenoids (1-9), together with 13 known congeners (10-22). The structures of the new compounds were elucidated by 1D and 2D NMR analysis in combination with HRESIMS data. The absolute configuration of the new natural products 1, 3, and 7 was determined using the TDDFT-ECD approach and confirmed for 1 by single-crystal X-ray determination through anomalous dispersion. The isolated compounds were tested for cytotoxicity against L5178Y, A2780, J82, and HEK-293 cell lines. Compound 1 was the most active metabolite toward L5178Y ce…
Headspace Volatile Composition of the Flowers of Caralluma europaea N.E.Br. (Apocynaceae)
2009
The volatile constituents of the flowers of Caralluma (Apteranthes) europaea (Guss.) N.E. Br. (Apocynaceae - Asclepiadoideae) from Lampedusa Island were analyzed by headspace method. The analyses allowed the identification and quantification of 41 compounds. The main components were, among the monoterpenoids, terpinolene (23.3%), a-terpinene (19.1%) and linalool (18.4%), whereas, among the carbonylic compounds the major constituents were heptanal (2.0%), octanoic acid (2.4%) and hexanoic acid (1.7%). It is worth to mention the presence of a nitrogen containing compound, indole (0.8%) and of a sulphur containing compound, dimethylsulphide (t). The compounds found in the flowers of C. europea…
Stereoselective Synthesis of Enantiomerically Pure Nupharamine Alkaloids from Castoreum
2009
An animalic note: The first total synthesis of the all-cis nupharamine 2, an alkaloid from beaver castoreum, is based on the stereoselective domino Mannich-Michael reaction of N-galactosylfurylaldimine to give 1 (Piv = pivaloyl), subsequent conjugate cuprate addition, and stereoselective protonation of the enolate. These reactions are all controlled by the carbohydrate. Protonation of the enolate after cleavage of the auxiliary leads to epimer 3.
Drug-induced expansion and differentiation of Vγ9Vδ2 T cells in vivo: The role of exogenous IL-2
2005
Human Vgamma9Vdelta2 T cells recognize nonpeptidic Ags generated by the 1-deoxy-d-xylulose 5-phosphate (many eubacteria, algae, plants, and Apicomplexa) and mevalonate (eukaryotes, archaebacteria, and certain eubacteria) pathways of isoprenoid synthesis. The potent Vgamma9Vdelta2 T cell reactivity 1) against certain cancer cells or 2) induced by infectious agents indicates that therapeutic augmentations of Vgamma9Vdelta2 T cell activities may be clinically beneficial. The functional characteristics of Vgamma9Vdelta2 T cells from Macaca fascicularis (cynomolgus monkey) are very similar to those from Homo sapiens. We have found that the i.v. administration of nitrogen-containing bisphosphonat…
Stereochemistry of terpene derivatives. Part 5: Synthesis of chiral lactones fused to a carane system—insect feeding deterrents
2006
Abstract Chiral iodo- 9, bromo- 10 and hydroxylactones 12 condensed with the carane system were obtained. In each case, the synthetic pathway led to an enantiomerically pure diastereoisomer to generate two stereogenic centers. Iodo- 9 and bromolactone 10 possess a γ-lactone group while the hydroxylactone 12 possesses a δ-lactone moiety situated trans to the gem-dimethylcyclopropyl ring. The structures of the products were confirmed by X-ray crystallography. These lactones were tested for antifeedant activity against storage pest insects.