# Benzochromanone and Benzochromene Natural Products: Synthetic Strategies and Total Syntheses

## TL;DR

This paper presents new synthetic methods to create natural products with benzochromanone and benzochromene structures, enabling the production of bioactive compounds like xanthones and blennolide C.

## Contribution

The paper introduces versatile and enantioselective synthetic strategies for benzochromanone and benzochromene natural products.

## Key findings

- Total syntheses of (±)-4-deoxyblennolide C, (+)-blennolide C, and gonytolide C were achieved.
- An asymmetric synthesis of (R)-(+)-teretifolione B and methylteretifolione B was successfully developed.
- A Diels–Alder reaction using benzyne and oxygenated furans enabled efficient benzochromene synthesis.

## Abstract

This account overviews our synthetic strategies for natural products featuring benzochromanone and benzochromene frameworks. The total synthesis of monomeric benzochromanones, particularly xanthones and benzochromanones is achieved. Key accomplishments include the development of a versatile synthetic approach for constructing xanthone frameworks via spirochromanone intermediates and the successful total syntheses of (±)‐4‐deoxyblennolide C, (+)‐blennolide C, and chromanone lactone gonytolide C. The asymmetric total synthesis of benzochromene (R)‐(+)‐teretifolione B and the first asymmetric synthesis of (R)‐(+)‐methylteretifolione B are also achieved. The Diels–Alder reaction between benzyne derived from chromene precursors and oxygenated furans enabled efficient access to benzochromene derivatives. The enantioselective synthesis of teretifolione B and related compound was accomplished through the enzymatic resolution of racemic chromenes, and the reaction conditions were investigated to improve regioselectivity in key steps. These synthetic routes provide access to a diverse array of benzochromanone and benzochromene derivatives with potential biological activity.

This work outlines synthetic strategies for natural products with benzochromanone and benzochromene cores. Key achievements include total syntheses of xanthones, blennolide C, gonytolide C, and teretifolione B. Spirochromanone intermediates, benzyne–furan Diels–Alder reactions, and enzymatic resolution enabled efficient and enantioselective access to diverse bioactive derivatives.© 2025 WILEY‐VCH GmbH