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ChemInform Abstract: Diastereoselective Synthesis of Spongian Diterpenes. Total Synthesis of the Furanoditerpene (-)-Spongia-13(16),14-diene.
2010
Abstract An effective diastereoselective synthesis of the marine-sponge metabolite (−)-spongia-13(16),14-diene 1 is achieved starting from S-(+)-carvone via a homochiral phenanthrenone as the key intermediate for the construction of the furan ring system. S-(+)-Carvone was transformed into the phenanthrenone 2a in six steps (53% overall yield), using an intramolecular Diels-Alder reaction as the key step. Conversion of the enone function in 2a into an epoxyaldehyde function followed by cyclisation and aromatisation in acid conditions completed the construction of ring D.
Composition of the essential oil fromflowerheads ofChrysanthemum coronarium L.(Asteraceae) growing wild in Southern Italy
2004
The essential oils from the aerial parts of Chrysanthemum coronarium L. (Asteraceae) growing wild in two different localities of Southern Italy, Lascari (L) and Palinuro (P), were obtained by hydrodistillation in a 0.13-0.16% yield. The oils were analysed by GC and GC-MS; 68 constituents, amounting to 89.0% of the oil (L), and 43 constituents, amounting to 91.6% of the oil (P), were identified. The trans-spiroketal-enol ether 2-(2,4- hexadiynylidene)-1,6-dioxaspiro(4,4)non-3-ene (trans-tonghaosu) with chrysanthenyl and lyratyl esters and camphor were the main components of the oils. Copyright © 2004 John Wiley & Sons, Ltd.
Hydroquinone derivatives from the marine-derived fungus Gliomastix sp.
2017
Eight new hydroquinone derivatives, gliomastins A–D (1–4), 9-O-methylgliomastin C (5), acremonin A 1-O-β-D-glucopyranoside (6), gliomastin E 1-O-β-D-glucopyranoside (7), and 6′-O-acetyl-isohomoarbutin (8), together with seven known analogues were isolated from the marine-derived fungus Gliomastix sp. Their structures were elucidated by extensive spectroscopic analysis including 1D and 2D NMR measurements aided by DFT NMR calculations as well as MS data. TDDFT-ECD and OR calculations were performed to determine the absolute configurations of 1 and the aglycones of 6 and 7. Compound 1 features a novel skeleton, biogenetically derived from a Diels–Alder reaction between derivatives of 11 and 1…
Organics in soda-anthraquinone black liquors from hot-water-extracted non-wood feedstocks
2019
The chemical compositions of black liquors (BLs) obtained from the soda-anthraquinone (AQ) pulping of untreated and hot-water-extracted non-wood feedstocks (okra stalk, miscanthus stalk, and wheat straw) were determined. These under-utilized renewable and widely available feedstocks could provide a cheaper source for producing fiber and precursors for manufacturing green chemicals. These BLs were mainly characterized in terms of carbohydrate-derived volatile carboxylic acids (acetic and formic acids) and non-volatile carboxylic acids (hydroxy acids) as well as lignin. Additionally, in each case, the average molar mass and molar mass distribution of the dissolved lignin were measured. Result…
Heterocyclisch anellierte Steroide aus 2-Hydroxymethylen-canrenon
1995
A-ring annulated heterocycles, the isoxazole 6, the pyrazoles 8 and the pyrimidines 9 are prepared starting from 2-hydroxymethylene canrenone 1. Binding studies were carried out with the compounds 1 and 6-8 using estrogen, progesterone, androgen, gluco- and mineralocorticoid receptors as well as the serum proteins SHBG and CBG: the substances were inactive on the receptor level. 1, 7 and 8a show weak binding affinity to CBG.
Trophic Transfer of Trace Elements in an Isotopically Constructed Food Chain From a Semi-enclosed Marine Coastal Area (Stagnone di Marsala, Sicily, M…
2012
Trace element accumulation is particularly important in coastal and transitional environments, which act as contaminant buffers between the continental and marine systems. We compared trace element transfer to the biota in two locations with different open-sea exposures in a semi-enclosed marine coastal area (Stagnone di Marsala, Sicily, Italy) using isotopically reconstructed food chains. Samples of sediment, macroalgae, seagrasses, invertebrates, fish, and bird feathers were sampled in July 2006 and analysed for stable carbon and nitrogen isotopes (δ(13)C, δ(15)N) and trace elements (arsenic [As], cadmium [Cd], total mercury [THg], and lead [Pb]). Trophic magnification factors were calcul…
CCDC 928582: Experimental Crystal Structure Determination
2013
Related Article: Sergiu Calancea, Dalice Pinero, David Poirot, Corine Mathoniere, Patrick Rosa, Rodolphe Clerac, Carolina Pejo, Raul Chiozzone,Francesc Lloret, Ricardo Gonzalez Hartje|2013|Polyhedron|64|294|doi:10.1016/j.poly.2013.05.021
CCDC 928581: Experimental Crystal Structure Determination
2013
Related Article: Sergiu Calancea, Dalice Pinero, David Poirot, Corine Mathoniere, Patrick Rosa, Rodolphe Clerac, Carolina Pejo, Raul Chiozzone,Francesc Lloret, Ricardo Gonzalez Hartje|2013|Polyhedron|64|294|doi:10.1016/j.poly.2013.05.021
CCDC 1503291: Experimental Crystal Structure Determination
2016
Related Article: Dimosthenis P. Giannopoulos, Luís Cunha-Silva, Rafael Ballesteros-Garrido, Rafael Ballesteros, Belén Abarca, Albert Escuer, Theocharis C. Stamatatos|2016|RSC Advances|6|105969|doi:10.1039/C6RA22953K
CCDC 2096753: Experimental Crystal Structure Determination
2021
Related Article: Juan-Ram��n Jim��nez, Buqing Xu, Hasnaa El Said, Yanling Li, Jurgen von Bardeleben, Lise-Marie Chamoreau, Rodrigue Lescou��zec, Sergiu Shova, Diana Visinescu, Maria-Gabriela Alexandru, Joan Cano, Miguel Julve|2021|Dalton Trans.|50|16353|doi:10.1039/D1DT02441H