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Combining Multiple Data Acquisition Systems to Study Corticospinal Output and Multi-segment Biomechanics

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Published on: January 9, 2016

Total synthesis of ningalin D.

Akiyuki Hamasaki¹, Jeffrey M Zimpleman, Inkyu Hwang

¹Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.

Journal of the American Chemical Society

|July 28, 2005

Summary

This study presents a concise nine-step synthesis of ningalin D, achieving a 19% overall yield. The novel approach effectively constructs the complex molecule and explores its potential in reversing multidrug resistance.

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Area of Science:

Organic Synthesis
Medicinal Chemistry
Chemical Biology

Background:

Ningalin D is a complex natural product with demonstrated cytotoxic and multidrug resistance (MDR) reversal activities.
Efficient synthetic routes are crucial for further biological evaluation and analog development.

Purpose of the Study:

To disclose a concise and effective total synthesis of ningalin D.
To investigate the cytotoxic and MDR reversal activities of ningalin D, its derivatives, and synthetic intermediates.

Main Methods:

A nine-step total synthesis featuring a 1,2,4,5-tetrazine --> 1,2-diazine --> pyrrole Diels-Alder strategy.
Key reactions include a double Dieckmann condensation, Suzuki coupling, and a Curtius rearrangement-initiated oxidative decarboxylation cascade.

Main Results:

Achieved a 19% overall yield for the total synthesis of ningalin D.
Successfully assembled the fully substituted pyrrole core and introduced sterically demanding aryl rings.
Demonstrated the cytotoxic and MDR reversal activities of synthesized compounds.

Conclusions:

The developed synthetic strategy is efficient and provides access to ningalin D and its analogs.
The biological evaluation provides insights into structure-activity relationships for cytotoxic and MDR reversal effects.