Total syntheses of (-)- and (+)-boronolide and their plant growth-inhibitory activity.
Biosci Biotechnol Biochem 2012;
76:1708-14. [PMID:
22972334 DOI:
10.1271/bbb.120317]
[Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Optically pure (+)- and (-)-boronolides were stereoselectively synthesized from yeast reductive products which had been obtained by yeast reduction of one common racemic substrate. The lactone structure of boronolide was constructed by Baeyer-Villiger oxidation. The stereochemistry of the yeast reduction products was studied to obtain the stereocenters at 5 positions of the dodecanolides of (+)- and (-)-boronolides. The stereochemistry of the 6 and 7 positions was obtained by AD-mix-α or β oxidation. The chiral center at the 8 position was constructed by employing (R)-(+)- or (S)-(-)-2-methyl-CBS-oxazaborolidine reduction or the Mitsunobu reaction. The plant growth-inhibitory activity against Echinochloa crusgalli L. of naturally occurring (+)-boronolide was higher than that of the (-)-boronolide.
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