Synthesis of Racemic, N-Benzylated Neoechinulin A and Isoneoechinulin A [¹]

 

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Abstract

Two N-benzylated analogues of the antioxidant, radical scavenging, and neuroprotective alkaloid neoechinulin A were prepared. Since, according to SAR studies, stereochemistry does not play an important role, both analogues were prepared in racemic form, using enaminone chemistry.

The term isoneoechinulin A is proposed by authors of this work and refers to the prenyl group replacing the isoprenyl group in neoechinulin A. This nomenclature is used for naming compound 2.

References and Notes

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The term isoneoechinulin A is proposed by authors of this work and refers to the prenyl group replacing the isoprenyl group in neoechinulin A. This nomenclature is used for naming compound 2.

A crystal structure of isoprenylated analogue 1 was established from monocrystal, but the diffraction data were poor for the isoprenylated region of the molecule; although the X-ray structure obtained unambiguously showed a Z orientation around the exocyclic double bond.