70 research outputs found
Divergent synthesis of (+)-tanikolide and its analogues employing stereoselective rhodium(II)-catalyzed reaction
In this study, we described the divergent synthesis of (+)-tanikolide and its analogues, such as (4S)- and (4R)-hydroxytanikolides, and nortanikolide, employing a stereoselective dirhodium(II)-catalyzed reaction to construct the quaternary chiral center of tanokolides. The key steps involve (a) a dirhodium(II)-catalyzed oxonium ylide formation–[2,3]-sigmatropic rearrangement, (b) an N-heterocyclic carbene-catalyzed ring-expansion lactonization of tetrahydrofurfural, or (c) an oxidative cleavage of tetrahydrofuran-5-methanol to γ-lactone using a 2-iodobenzamide catalyst. This route would provide high flexibility for analogue synthesis because the long side chain can be introduced at a later stage in the synthesis
Stereoselective synthesis of 1,3-disubstituted dihydroisoquinolines vial-phenylalanine-derived dihydroisoquinoline N-oxides.
The preparation of chiral pool-derived nitrone 3 and its use in the protecting-group free, stereoselective synthesis of a range of 1,3-disubstituted tetrahydroisoquinolines is described. Grignard reagent additions to nitrone 3 yielded trans-1,3-disubstituted N-hydroxytetrahydroisoquinolines 6 with good levels of selectivity, while 1,3-dipolar cycloadditions to this nitrone provided access to 3-(2-hydroxyalkyl)isoquinolines 12 as single diastereomers
Alkyl and aryl sulfonyl p-pyridine ethanone oximes are efficient DNA photo-cleavage agents
D- and L-Erythrose as Sources of Chiral Quaternary Carbon Centers. Total Synthesis of (-)-Malyngolide and (+)-Tanikolide.
Formation of New Alkynyl(phenyl)iodonium Salts and Their Use in the Synthesis of Phenylsulfonyl Indenes and Acetylenes
The preparation of phenylsulfonyl indene derivatives and phenylsulfonyl- acetylenes from readily available alkynyl(phenyl)iodonium tetrafluoroborates and triflates was investigated using phenylsulfinate as nucleophile
1,3-Dipolar Cycloadditions in the Synthesis of Carbohydrate Mimics. Part 3. Azides, Diazo Compounds and Other Dipoles
THE EFFECTS OF ANTICIPATED JOB EMBEDDEDNESS AND SOCIAL NEEDS ON ORGANIZATIONAL ATTRACTION
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