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Updated: Aug 17, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
P-heterocyclic building blocks: application to the stereoselective synthesis of P-sugars
Diana S Stoianova1, Alan Whitehead, Paul R Hanson
1Department of Chemistry, 1251 Wescoe Hall Drive, Malott Hall, University of Kansas, Lawrence, KS 66045-7582, USA.
Abstract:
A strategy relying on the utilization of stereoselective additions to allyldiphenylphosphonate esters and subsequent ring-closing metathesis (RCM) to access P-chiral P-heterocyclic building blocks for the synthesis of phosphono sugars is described. These building blocks possess several attractive components, including the following: (i) P(2) and C(6) stereogenic centers for directing stereoselective transformations; (ii) an activated C(3) methylene group that promotes base-mediated olefin transposition to generate vinyl phosphonates available for further stereoselective reactions; and (iii) a P(2)-stereogenic center containing an exchangeable phosphonate ester armed to attenuate the "stereochemical environment" at phosphorus. Taken collectively, these attributes contribute to a concise method for the stereoselective synthesis of an array of P-sugars.
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