2225-79-8Relevant articles and documents
Synthesis of (+)-8-deoxyvernolepin and its 11,13-dihydroderivative. A novel reaction initiated by sulfene elimination leads to the 2-oxa-cis-decalin skeleton
Barrero, Alejandro F.,Oltra, J. Enrique,Alvarez, Miriam,Rosales, Antonio
, p. 5461 - 5469 (2002)
The title compounds are interesting candidates for antifungal screening. This paper describes the enantiospecific synthesis of these compounds starting from (+)-costunolide isolated from a commercially available extract. We used two novel reactions as key synthetic steps in this work: the acid-induced cyclization of an δ,ε-epoxy ester, which stereoselectively gave a hydroxymethyl-substituted δ-lactone, with the hydroxyalkyl group in the desired β-equatorial disposition, and a reaction cascade, initiated by a base-promoted sulfene elimination, which led to a 10-oxiranyl-2-oxa-cis-decalin from the mesylate of a trans-fused δ-lactone. We also found that the reaction between selenium dioxide and the 1,5-diene system of elemanolides gave selenadecalins analogous to natural eudesmanolides. Our results prove that the synthetic strategy employed, on the basis of biomimetic concepts, is a useful procedure for the enantiospecific preparation of (+)-vernolepin-related compounds from accessible germacrolides.
Total Synthesis of (+)-Dihydrocostunolide via Tandem Cope-Claisen Rearrangement
Raucher, Stanley,Chi, Ki-Whan,Hwang, Ki-Jun,Burks, John E.
, p. 5503 - 5505 (1986)
The total synthesis of (+)-dihydrocostunolide via tandem Cope-Claisen rearrangement has been accomplished.
Sesquiterpene lactones with potential use as natural herbicide models (I): trans, trans-germacranolides
Macias, Francisco A.,Galindo, Juan C. G.,Castellano, Diego,Velasco, Raul F.
, p. 4407 - 4414 (1999)
A structure-activity study to evaluate the effect of the trans,trans- germacranolide sesquiterpene lactones costunolide, parthenolide, and their 1,10-epoxy and 11,13-dihydro derivatives (in a range of 100-0.001 μM) on the growth and germination of several mono and dicotyledon target species is accomplished. Results are compared with those obtained in the same bioassay with an internal standard, the commercial herbicide Logran, to validate the results with a known active formulation and to compare the results with a commercial product to test their potential use as natural herbicide models. These compounds appear to have a more selective effects on the radicle growth of monocotyledons. Certain factors such as the presence of nucleophile- acceptor groups and their accessibility enhance the inhibitory activity. The levels of radicle inhibition obtained with some compounds on wheat are totally comparable to those of Logran and allow to propose them as lead compounds.
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Winter,Lindauer
, p. 955,956,958 (1976)
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