title: The antifungal activity of widdrol and its biotransformation by Colletotrichum gloeosporioides (penz.) Penz. & Sacc. and Botrytis cinerea Pers.: Fr.
abstract: Widdrol (1) was tested against the necrotrophic plant pathogens Botrytis cinerea and Colletotrichum gloeosporioides. While 1 was found to be inactive against C. gloeosporioides, it showed a selective and effective control of B. cinerea, significantly inhibiting the mycelial growth of the fungus at concentrations of 100 ppm and above. In addition, the biotransformation of 1 by both fungi was studied. Incubation with C. gloeosporioides and B. cinerea afforded four and one biotransformation products (2-6), respectively. Biotransformation with C. gloeosporioides was highly regioselective, yielding for the most part oxidation products at C-10: 10-oxowiddrol (2), 10beta-hydroxywiddrol (3), 10alpha-hydroxywiddrol (4), and 14alpha-hydroxywiddrol (5). The structures of all products were determined on the basis of their spectroscopic data, including coupling constants, two-dimensional NMR analysis (heteronuclear multiple quantum coherence, heteronuclear multiple bond correlation, and nuclear Overhauser enhancement spectroscopy), and nuclear Overhauser effect. The biotransformation products were then tested against B. cinerea and found to be inactive. These results shed further light on the structural modifications, which may be necessary to develop selective fungal control agents against B. cinerea.
authors.affiliation: Instituto de Investigaciones Fundamentales en Agricultura Tropical Alejandro de Humboldt (INIFAT), Calle:2, Esq. 1, Santiago de las Vegas, CP 17200, Cuba.
authors.forename: Yarelis Ortíz
authors.initials: YO
authors.lastname: Nuñez
authors.forename: Iraida Spengler
authors.initials: IS
authors.lastname: Salabarria
authors.forename: Isidro G
authors.initials: IG
authors.lastname: Collado
authors.forename: Rosario
authors.initials: R
authors.lastname: Hernandez-Galan
mesh_terms: D001567:Benzocycloheptenes / Q000378:metabolism* / Q000494:pharmacology*; D020171:Botrytis / Q000187:drug effects* / Q000378:metabolism; D020231:Colletotrichum / Q000187:drug effects* / Q000378:metabolism; D005659:Fungicides, Industrial / Q000378:metabolism / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy
chemical_list: D001567:Benzocycloheptenes; D005659:Fungicides, Industrial; C078670:widdrol