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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Identification of 2,3-dihydro-gamma-ionylideneethanol in Cercospora cruenta
H Yamamoto1, M Inomata, T Uchiyama
1Faculty of Agriculture, Niigata University, Ikarashi, Japan. hirotaka@agr.niigata-u.ac.jp
Abstract:
During our scrutiny of GC-EI-MS date for C15 alcohols as putative intermediates on the ABA biosynthetic pathway in Cercospora cruenta, a trace amount of 5-[2',2'-dimethyl-6'-methylene-1'-cyclohexyl]-3-methyl-4-penten-1-ol (2,3-dihydro-gamma-ionylideneethanol) was identified. Feeding experiments indicated that this compound was not an intermediate to ABA, but a catabolite that originated from gamma-ionylideneacetaldehyde. The stereochemistry of 2,3-dihydro-gamma-ionylideneethanol was deduced to be (3R,1'S) from a comparison with an authentic specimen prepared via baker's yeast asymmetric reduction.
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