Conformational and Structural Analysis of a ter‐Cyclopentane Scaffold for Molecular Recognition

Abstract

Well-defined oligomers of cycloalkanes comprise a relatively unstudied class of organic compounds, and may have general utility in the development of receptors for biologically relevant molecules. We have investigated the solution structure of a ter-cyclopentane member of this class by molecular modeling and by NMR spectroscopy. We find that the molecular ensembles derived from conformational searches incorporating NMR-derived restraints are in excellent qualitative agreement with unrestrained molecular mechanics conformation searches. The ter-cyclopentane scaffold adopts an ex-

Norbornene in Organic Synthesis

“…Starting from norbornene, oxidative reaction with KMnO 4 on CuSO 4 provided dialdehyde 202 in nearly quantitative yield by cleavage of the double bond. 115 Similarly, the oxidation of norbornene in t BuOH gave the corresponding dialdehyde 202 in 60% yield; this was utilized for the preparation of the useful carbocycle 204 after further functional group interconversions (Scheme 56). 116 Ru-catalyzed oxidation reactions to access dialdehydes were also studied by Yang and Che respectively (Scheme 57).…”

Selective Recognition of Alkyl Pyranosides in Protic and Aprotic Solvents

“…In principle, highly substituted cycloalkanes should provide some of the same benefits as arenes: a hydrophobic surface and conformational control of pendant functionality via avoidance of “anti” interactions (though this control is less stringent than that provided by hexasubstituted benzenes). Indeed, we have successfully employed cycloalkane oligomers as conformational control elements in the development of receptors for lipid A . This led us to begin considering the possibility that other cycloalkane-based scaffolds might have utility as receptors for monosaccharides.…”