The First Total Synthesis of the Proposed Structure of Montiporyne E

Abstract

Montiporyne E, a novel diacetylenic lactam isolated from the stony coral Montipora sp., was shown to exhibit cytotoxicity against certain solid tumor cells. Construction of a suitably functionalized α,β-unsaturated lactam for palladium-catalyzed couplings was realized via a Beckmann rearrangement. Subsequent Sonagoshira coupling with a known alkyne chain efficiently afforded the alleged structure of the natural product.

Key words

synthesis - Beckmann - lactams - coupling reactions - alkynes

References

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10

The oxime mixture could be recrystallized from EtOH to give pure syn-oxime 5 in 43% yield.

15

The ¹H and ¹³C NMR spectra of natural montiporyne E were provided by Dr. Jee H. Jung, College of Pharmacy, Pusan National University, Korea.