Biosynthesis of fungal meroterpenoids

Abstract

Covering: up to September 2015. Meroterpenoids are hybrid natural products that partially originate from the terpenoid pathway. The meroterpenoids derived from fungi display quite diverse structures, with a wide range of biological properties. This review summarizes the molecular bases for their biosyntheses, which were recently elucidated with modern techniques, and also discusses the plausible biosynthetic pathways of other related natural products lacking genetic information. (Complementary to the coverage of literature by Geris and Simpson in Nat. Prod. Rep., 2009, 26, 1063-1094.).

A Concise Route to the Strongylophorines

“…[3, 4] Meroterpenoids are a terpenoid subclass resulting from hybrid biosynthetic pathways that fuse terpene substructures with polyketide or alkaloid components. [5,6] Our laboratory takes an interest in natural products with challenging structural features and unclarified biological activities.[7] The strongylophorines (STRs, Figure S1 in the Supporting Information) are a family of meroditerpenoids initially isolated from the marine sponges Strongylophora durissima and Petrosia cortica, [8, 9b] with members displaying diverse biological activity, including neuroprotective effects (STR-8), [9a] anti-invasive activity (STR-26), [9b-d] and inhibitory activity against HIF-1 (STR-2, 3, and 8).[9e] To date, no syntheses of any of the strongylophorines have been reported. Structurally, STR-2 (1, Figure 1) occupies a central position within the STR-family since this compound provides a favorable point of diversification and contains the synthetically challenging bicyclic d-lactone functionality at the AÀB ring junction found in most of the bioactive STRs.…”

3,5‐Dimethylorsellinic Acid Derived Meroterpenoids from Eupenicillium sp. 6A‐9, a Fungus Isolated from the Marine Sponge Plakortis simplex

“…[30] Notably, the completely elucidated pathways for austinol [21,22,27] and berkeleydione, [29] for which the known compounds preaustinoid A1 (7) and preaustinoid A3 (10) acquired here are biosynthetic intermediates, enabled us to propose detailed mechanisms for the biosynthesis of the five related new meroterpenoids 1-5 (Scheme 1).…”

“…Thus, given the assigned austinol biosynthetic pathway, [30] the mechanisms for providing preaustinoid A1 (7) and preaustinoid A3 (10) within six steps can be described as follows (Scheme 1a). An epoxide-initiated cyclization of a generates a tetracyclic intermediate, protoaustinoid A (11).…”

The Chemistry of the Sesquiterpene Alkaloids

“…Terpenoids also take part in mixed biosynthetic processes joining with NPs from other origins (meroterpenoids), 4 or by uniting with other terpenoids (oligoterpenoids), 5 and by including atoms not usual to their normal biosynthesis. The tremendous structural variation of terpenoids (and NPs) can easily be verified by reading the "Hot off the Press" articles published bimonthly in Natural Product Reports.…”