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Updated: Dec 6, 2025

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Synthesis and Stereochemical Assignment of Conioidine A: DNA- and HSA-Binding Studies of the Four Diastereomers
Ryan Shaktah1, Laura Vardanyan1, Elroma David1
1Department of Chemistry and Biochemistry, California State University, Northridge, 18111 Nordhoff Street, Northridge, California 91330, United States.
Abstract:
Conioidine A (1), isolated in 1993 with unknown relative and absolute configuration, was suggested to be a DNA-binding compound by an indirect technique. Four stereoisomers of conioidine A have been synthesized from d- and l-proline, and the natural product has been identified as possessing (4R,6R) absolute configuration. Binding of the conioidine diastereomers to calf thymus DNA (CT DNA) and human serum albumin (HSA) has been investigated by fluorescence spectroscopy and isothermal titration calorimetry (ITC). All stereoisomers display at least an order of magnitude weaker binding to DNA than the control compound netropsin; however, a strong association with HSA was observed for the (4R,6S) stereoisomer.
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