An Unprecedented Octahydro-3H-oxeto[2,3,4-ij]isochromene Ring System Formed by a Trichloromethyl-Anion-Induced Reaction Cascade

Abstract

Sigillin A is a unique polychlorinated, insect repellent natural product, isolated recently from springtails. During the exploitation of an access to such compounds using a trichloromethyl-anion-induced epoxide opening as key step a new synthetic compound was found. A five-step cascade reaction leads to an oxeto[2,3,4-ij]isochromene compound, including a rare oxetane acetal as well as an trichloroenol ether group. Biological data on the antibacterial properties of this compound and sigillin A are reported as well.

Key words

sigillin - springtails - dichlorocarbene - chlorinated natural products - hydrobenzopyranone - dimethyldioxirane - oxetane acetal - trichloroenol ether

• References and Notes

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