The first total synthesis of the tetracyclic alkaloid (-)-acutumine is described. Key reactions include an asymmetric ketone allylation mediated by Nakamura's chiral allylzinc reagent, an anionic oxy-Cope rearrangement, and the Lewis acid-promoted cyclization of an amine onto an alpha,beta-unsaturated dimethyl ketal.

A catalytic, enantioselective γ-alkylation of α,β-unsaturated malonates and ketoesters is reported. This strategy entails a highly regio- and enantioselective iridium-catalyzed α-alkylation of an extended enolate, and a subsequent translocation of chirality to the γ-position via a Cope rearrangement.

In reactions with weak dienophiles, cyclooctatetraene (COT) often yields 2:1 adducts possessing the fluxional bicyclo[5.1.0]octadiene moiety. They undergo fast, nearly degenerate Cope rearrangement with an activation barrier similar to that of the parent dihydrobullvalene. Irradiation to excite the carbonyl moiety induces an intramolecular Paterno-Buchi cyclization yielding endo-oxetanes and si...

A set of mild processes for the conversion of vinyl cyclopropyl diazo ketones to highly functionalized cycloheptadienones and vinyl cyclopentenones by use of a target-inspired tandem Wolff/Cope rearrangement sequence is described. A divergent reaction course of the vinyl cyclopropyl diazo ketone substrates under sono- or photochemical activation provides good to excellent yields (55-98%) of the...

Pinostrobin (5-hydroxy-7-methoxyflavanone) obtained in relatively large amounts from fingerroot (Boesenbergia pandurata) was converted to its C-6 and C-8 prenylated derivatives. The Mitsunobu reaction, europium(III)-catalyzed Claisen-Cope rearrangement, and Claisen reaction coupled with cross-metathesis were used as the key steps. Using a sealed-vessel microwave reactor, the Mitsunobu and Clais...

in order to find the susceptibility of the claisen rearrangement and next proton shift reaction of ally) aryl etherto the substiment effects in pan position, the kinetic and the:rmodynamie parameters are calculated at the33 ltp level using 6-3110. b asis set. the calculated activation energies for the rearrangements and protonshift reactions are around 3133 kcaumol and 52.16 kcal/mol, nap.. liv...

Background: Mammalian cell division is regulated by a complex includes cyclin-dependent kinases (Cdks) and cyclins, Cdk/cyclin complex. The activity of the complex is regulated by Cdk inhibitors (CKIs) compressing CDK4 (INK4) and CDK-interacting protein/kinase inhibitory protein (CIP/KIP) family. Hypermethylation of CKIs has been reported in various cancers. DNA methyltransferase inhibitors (DN...