Botcinins E and F and Botcinolide from Botrytis cinerea and structural revision of botcinolides.
Botcinins E and F were isolated together with the known botcinolide. The structures of botcinins E and F were determined to be 3-O-deacetylbotcinin A (5) and 3-O-deacetyl-2-epi-botcinin A (6), respectively, by spectroscopic methods and chemical conversion. The structure of botcinolide was revised on the basis of spectroscopic data and chemical conversion. Botcinolide was originally reported as a nine-membered lactone (7), but the revised structure is the seco acid of botcinin E (13). Thus botcinolide is renamed botcinic acid, and homobotcinolide is renamed botcineric acid. Reinvestigation of the spectroscopic data reported for all botcinolide analogues indicates that 4-O-methylbotcinolide and 3-O-acetyl-2-epibotcinolide are the same as a methyl ester of botcinic acid (13a) and botcinin A (1), respectively, and that 2-epibotcinolide may be the same as botcinin E (5). Compounds 5, 6, and 13 showed weak antifungal activity against Magnaporthe grisea, a pathogen of rice blast disease.
Tani
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Department of Agricultural Chemistry, Faculty of Agriculture, Tottori University, Tottori 680-8553, Japan.
Koshino
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Sakuno
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E
Cutler
H G
HG
Nakajima
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H
D020171:Botrytis / Q000737:chemistry*; D003651:Decanoates / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D020082:Magnaporthe / Q000187:drug effects / Q000472:pathogenicity; D015394:Molecular Structure; D010935:Plant Diseases / Q000382:microbiology; D011753:Pyrones / Q000737:chemistry* / Q000302:isolation & purification*
D003651:Decanoates; D007783:Lactones; D011753:Pyrones; C511119:botcinin E; C511120:botcinin F; C101236:botcinolide; C101235:homobotcinolide