Using the Sonogashira Reaction for Preparing a New Fragment Library based on the 3-alkynylimidazo[1,2-a]pyridine Scaffold

Title:Using the Sonogashira Reaction for Preparing a New Fragment Library based on the 3-alkynylimidazo[1,2-a]pyridine Scaffold

Volume: 13 Issue: 7

Author(s): Caroline Castera-Ducros, Hussein El-Kashef, Melanie Piednoel, Vincent Remusat, Jean-Claude Teulade, Pierre Verhaeghe, Pascal Rathelot and Patrice Vanelle

Affiliation:

Keywords: 3-halogenoimidazo[1, 2-a]pyridines, Sonogashira cross-coupling reaction, 3-alkynylimidazoimidazo[1, 2-a]pyridine.

Abstract: Background: The imidazo[1,2-a]pyridine ring has been widely studied by medicinal chemists and displays great pharmaceutical potential.

Methods: In a view to prepare a library of new molecules including an imidazo[1,2-a]pyridine scaffold, as original fragments for the conception of novel anti-protozoal compounds, the Sonogashira crosscoupling reaction between 3-halogenoimidazo [1,2-a]pyridines and phenylacetylene was studied.

Results: From 3-iodoimidazo[1,2-a]pyridine, chosen as an optimal substrate for conducting the reaction at room temperature in 2 hours, a variety of terminal alkynes was involved into the reaction, leading to a series of 16 new 3-phenyethynylimidazo [1,2-a]pyridines in satisfying to good yields (50-82%) and 4 additional derivatives in moderate yields (30-40%).

Conclusion: Such synthetic approach appears efficient for the rapid synthesis of imidazopyridine chemical libraries. The corresponding derivatives will next be evaluated for their anti-infective properties.

Cite this article as:

Castera-Ducros Caroline, El-Kashef Hussein, Piednoel Melanie, Remusat Vincent, Teulade Jean-Claude, Verhaeghe Pierre, Rathelot Pascal and Vanelle Patrice, Using the Sonogashira Reaction for Preparing a New Fragment Library based on the 3-alkynylimidazo[1,2-a]pyridine Scaffold, Letters in Organic Chemistry 2016; 13 (7) . https://dx.doi.org/10.2174/1570178613666160919124456