Colletochlorins E and F, New Phytotoxic Tetrasubstituted Pyran-2-one and Dihydrobenzofuran, Isolated from Colletotrichum higginsianum with Potential Herbicidal Activity

Abstract

A new tetrasubstituted pyran-2-one and a new dihydrobenzofuran, named colletochlorins E and F (1 and 2, respectively), were isolated from the culture filtrates of the fungus Colletotrichum higginsianum together with the already known colletochlorin A, 4-chloroorcinol, and colletopyrone. Colletochlorin E, the main metabolite, and colletochlorin F were characterized by spectroscopic (NMR, HRESIMS) and chemical methods as 3-[7-chloro-4-hydroxy-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydrobenzofuran-5-ylmethyl]-4-hydroxy-5,6-dimethylpyran-2-one and 7-chloro-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydrobenzofuran-4-ol, respectively. The absolute configuration 2'S of 1 was deduced by X-ray diffractometric analysis, whereas 2S of 2 was deduced by comparison of its NMR and CD data with those of 1. When assayed by leaf puncture on Sonchus arvensis and tomato leaves, 2 caused quite large necrosis (>1 cm), whereas 4-chloroorcinol proved to be the most active compound. These results were confirmed by those obtained in assays on Lemna minor and Phelipanche ramosa seed germination. Furthermore 1, colletochlorin A and colletopyrone were less or modestly active in the latter assay, respectively. Interestingly, the phytotoxicity was not associated with an antibiotic activity, whereas only 4-chloroorcinol and colletochlorin F exhibited zootoxic activity.

H3K4 trimethylation by CclA regulates pathogenicity and the production of three families of terpenoid secondary metabolites in Colletotrichum higginsianum

“…Studies on the numerous toxins and other secondary metabolites produced by Colletotrichum species were reviewed by (García‐Pajón and Collado, ). However, natural products produced by C. higginsianum were only reported recently (Cimmino et al ., ; Masi et al ., ; ). These include the diterpenes subglutinol A and BR‐050, that were previously isolated from Fusarium subglutinans (Lee et al ., ) and Penicillifer superimpositus (Terumi et al ., ).…”

“…In 2016, Cimmino and co‐workers reported two epimers of subglutinol A and BR‐050, which they called higginsianin A and B, respectively. Colletochlorin A (Kosuge et al ., ), colletochlorins E‐H, 4‐chloroorcinol (Monde et al ., ), colletopyrone (Gohbara et al ., ) and colletopyrandione were also isolated from the same strain of C. higginsianum as that studied here (Masi et al ., ; ). In the present study, we discovered five novel terpenoid compounds from cultures of the ∆ cclA mutant, including two additional members of the colletochlorin family (colletorin D and colletorin D acid), two new higginsianin analogues (higginsianin C and 13‐ epi ‐higginsianin C) as well as an inositol‐conjugated form of sclerosporin that we called sclerosporide.…”

Structure, Synthesis of Hierridin C and Discovery of Prevalent Alkylresorcinol Biosynthesis in Picocyanobacteria

“…The halogenated 5-methylresorcinol derivative 4-chloroorcinol was isolated from the phytopathogenic fungus Colletotrichium higgisianum and induced chlorosis in plant leaves, inhibited seed germination and was also toxic to the crustacean Artemia salina. 8 The monochasiols are a series of long chain alkylresorcinols, with a single chlorinated carbon in between the resorcinol hydroxy groups, that have been isolated from the slime mold Dictyostelium and have mild immunosuppressive activity. 9 Other examples include a series of dimerized chlorinated short-chain alkylresorcinols -the spiromastols -that have been reported recently from a deep-sea fungus and have antibacterial activity.…”

Life cycle assessment of dryland paddy farming in Ngadirojo District, Pacitan

“…Chemical control uses by some farmers because this mechanism is easy, inexpensive, and effective. Nevertheless, chemical control has a negative impact for ecosystem [23]. So, other farmers prefer for implemented mechanical control as an effort to keep the sustainable of the ecosystem.…”