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Total syntheses of isonaamine C and isonaamidine E
Heather M Lima1, Beatriz J Garcia-Barboza, Nicole N Khatibi
1Department of Chemistry & Biochemistry, University of Texas at Arlington, Arlington, TX 76019.
Tetrahedron Letters
|December 6, 2011
Summary
Researchers achieved the total synthesis of two marine alkaloids, isonaamine C and isonaamidine E, from the Leucetta sp. sponge. These syntheses were completed in 6 and 7 steps, respectively, utilizing novel chemical transformations.
Area of Science:
- Marine Natural Products Chemistry
- Organic Synthesis
- Medicinal Chemistry
Background:
- Marine sponges are a rich source of structurally diverse alkaloids with potential biological activities.
- Leucetta sp. sponges yield unique alkaloid compounds, including isonaamine C and isonaamidine E.
- Efficient synthetic routes to these complex molecules are crucial for further study.
Purpose of the Study:
- To achieve the first total synthesis of isonaamine C and isonaamidine E.
- To develop a scalable and efficient synthetic strategy for these marine alkaloids.
- To provide access to these compounds for further biological evaluation.
Main Methods:
- Total synthesis starting from a 4,5-diiodoimidazole derivative.
- Grignard-mediated halogen-metal exchange for side-chain installation.
- Lithiation and quenching with trisyl azide for C2 substitution, followed by hydrogenation.
- Hydantoin ring formation using activated parabanic acid.
Main Results:
- Successful 6-step total synthesis of isonaamine C.
- Successful 7-step total synthesis of isonaamidine E, derived from isonaamine C.
- Demonstrated utility of halogen-metal exchange and lithiation strategies.
Conclusions:
- The total syntheses of isonaamine C and isonaamidine E were successfully accomplished.
- The developed synthetic routes provide valuable access to these marine alkaloids.
- This work enables further investigation into the potential applications of these compounds.
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