The total synthesis of (+)-9-epi-dictyostatin (1b), a diastereomer of the antimitotic marine-sponge-derived macro-tide (-)-dictyostatin (1a), was achieved by creating 11 stereogenic centers and 4 stereogenic double bonds...
We investigated the behavior of the extensively used system trifluoromethanesulfonic anhydride/sulfoxide in the absence of any added nucleophilic species. We show here, with the help of F-19 NMR spectroscopy, that in the...
A series of bifunctional primary amine-thiophosphoramides were synthesized, which proven to be effective organocatalysts for the asymmetric Michael reaction of acetone to both aryl and alkyl nitro olefins in the presence...
The present communication reports on the synthesis of alkoxyamines by hydroboration of olefins with catecholborane and subsequent oxidation by using nitroxides. Oxidation occurs via a radical process and the intermediate...
An iron-catalyzed ortho-functionalization of phenols was developed. The reactions of simple phenols with alpha-hydroxy ketones provide a novel and efficient. method to construct 2'-hydroxyphenyl-1,2-dione derivatives.
The rare phytoecdysteroid canescensterone is a potent activator of both natural and engineered ecdysteroid receptor (EcR) gene-expression systems. This steroid also shows a remarkable selectivity towards non-lepidopteran...
The synthesis of substituted 1,8-diarylnaphthalenes is reported. A bis-Suzuki coupling strategy starting from 1,8-di-bromonaphthalene provides a useful and general route to the 1,8-diarylnaphthalene scaffold. In this con...
The synthesis of new chiral ionic liquids with chiral anions is described. Chiral sulfate anions were prepared from alcohols of the "chiral pool" in good yields. Subsequent ion metathesis resulted in new salts with tetra...
The novel and simple synthesis of tricyclic chromenoisoxazolidine frameworks by using Baylis-Hillman derivatives through in situ formation of nitrones followed by an intramolecular [3+2] dipolar cycloaddition reaction se...
An efficient chemoenzymatic synthesis of both enantiomers of fagomine, as well as of cis and trans-4-hydroxypipecolic acid is reported. The synthesis starts from commercial 8-valerolactam which, after a Pd-catalyzed meth...
The alpha-alkylation of deprotonated N-aryl-alpha-aminonitriles with alpha-bromoesters furnishes intermediates that can be cyclized to 4-quinolones upon microwave irradiation. Alternatively, base-induced dehydrocyanation...
Unsaturated delta-lactams are cyclopropanated with the aid of diazo compound decomposition catalysed by metal complexes. A study of the reaction conditions, stereochemical outcome and group protection is reported. The re...
NHCs promote the efficient chlorination of unsymmetrical disubstituted ketenes with a range of chlorinating agents; chiral NHCs display promising levels of asymmetric induction in the chlorination process with up to 61 %...
Experimental and computational DFT studies of the Diels-Alder (DA) reaction mechanism for the series of 2H-pyran-2-ones 1 and non-symmetrically substituted alkynes 2, 10, and 11 were undertaken. Several 2H-pyran-2-ones 1...
Treatment of gamma-disubstituted beta,gamma-unsaturated hydroxamates with bis(collidine)bromine(I) hexafluorophosphate led mainly to the formation of cyclic bromo imidates - the thermodynamic products. Unsaturated cyclic...
Treatment of 3-alkoxycarbonyl-4-acyl- or 3,4-dialkoxycarbonyl-substituted isoxazolidines with a mild base, such as tetrabutylammonium fluoride, affords beta-enaminones and/or 3-methylamino-2(5H)-furanones according to th...