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Updated: Apr 12, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Dienals derived from pyridinium salts and their subsequent application in natural product synthesis
Jens M J Nolsøe1, Marius Aursnes1, Jørn E Tungen1
1School of Pharmacy, Department of Pharmaceutical Chemistry, University of Oslo, P.O. Box 1068 Blindern, N-0316 Oslo, Norway.
Abstract:
Transformation of quaternary pyridinium compounds into functionalized conjugated dienes can be adapted to natural product synthesis with great effect. Most conspicuously, the transformation has been employed in the preparation of polyenic structures. However, in a more convoluted application, polycyclic systems have arisen from elaboration of the diene motif. The goal of the present account is to survey the utility of dienals derived from pyridinium salts as the means to establish molecular architecture featured in natural products.
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