Syntheses and Phytotoxicity of All Stereoisomers of 6-(2-Hydroxy-6-phenylhex-1-yl)-5,6-dihydro-2<i>H</i>-pyran-2-one and Determination of the Effect of the α,β-Unsaturated Carbonyl Structure and Hydroxy Group Bonding to Chiral Carbon
作者:Ryota Ochi、Hisashi Nishiwaki、Satoshi Yamauchi
DOI:10.1021/acs.jafc.9b05507
日期:2019.11.13
All four stereoisomers of naturally occurring 6-(2-hydroxy-6-phenylhex-1-yl)-5,6-dihydro-2H-pyran-2-one (1) were synthesized by employing yeast-reduction products with high optical purity [from 95% enantiomeric excess (ee) to more than 99% ee], and then their phytotoxicities against lettuce and Italian ryegrass were evaluated. In the Italian ryegrass seedlings test, (6S,2′R)-1 showed the most potent
天然存在的 6-(2-羟基-6-苯基己-1-基)-5,6-二氢-2 H-吡喃-2-酮 ( 1 ) 的所有四种立体异构体均采用高光学酵母还原产物合成。纯度[从 95% 对映体过量 (ee) 到 99% ee 以上],然后评估它们对生菜和意大利黑麦草的植物毒性。在意大利黑麦草幼苗试验中,(6 S ,2′ R )- 1对芽(IC 50 = 260 μM)和根(IC 50 = 43.2 μM)表现出最有效的立体特异性活性,与其他黑麦草有显着差异。立体异构体。 (6 S ,2' R ) -1中也观察到了对意大利黑麦草种子的最高种子发芽抑制活性,在 1000 μM 时显示出与对照相比的 53% 的发芽率。这种有利的 (6 S ,2' R ) 立体化学被用于合成 α,β-二氢、2'-脱羟基和 2'-甲氧基衍生物13 – 15 。通过使用这些衍生物的试验,确定了5,6-二氢-α-吡喃酮6-烷基链上的α