title: Cohaerins A and B, azaphilones from the fungus Hypoxylon cohaerens, and comparison of HPLC-based metabolite profiles in Hypoxylon sect. Annulata.
abstract: Azaphilones, named cohaerins A and B were isolated from stromata of the xylariaceous ascomycete Hypoxylon cohaerens. Their absolute structures were determined by spectroscopic methods (2D NMR, MS, IR, UV CD), and subsequently confirmed by acetylation. Stromatal metabolite profiles of several taxa of Hypoxylon sect. Annulata were also generated using analytical HPLC with diode array and MS detection. The cohaerins were neither found in other Hypoxylon spp., nor in other Xylariaceae. However, they were present even in holotype material of H. cohaerens, collected over 200 years ago. The binaphthalene BNT was also omnipresent in sect Annulata, and its derivatives, the benzo[j]fluoranthenes daldinone A and truncatone, as well as presumably related compounds. These fungi were found devoid of other types of azaphilone pigments of the Xylariaceae, such as mitorubrins and daldinins, the latter of which are widespread in certain groups of Hypoxylon sect. Hypoxylon. Hence, chemotaxonomic data largely support the current generic concept. The original source of truncatone was identified as Hypoxylon annulatum.
authors.affiliation: Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima 770-8514, Japan.
authors.forename: Dang Ngoc
authors.initials: DN
authors.lastname: Quang
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nomura
authors.forename: Hartmund
authors.initials: H
authors.lastname: Wollweber
authors.forename: Veronika
authors.initials: V
authors.lastname: Hellwig
authors.forename: Jacques
authors.initials: J
authors.lastname: Fournier
authors.forename: Marc
authors.initials: M
authors.lastname: Stadler
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Asakawa
mesh_terms: D001203:Ascomycota / Q000737:chemistry / Q000378:metabolism*; D001578:Benzopyrans / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D015394:Molecular Structure
chemical_list: D001578:Benzopyrans; C501693:cohaerin A; C501692:cohaerin B