The enolates of various propiophenones, chromanones, and also analogues of naturally occurring flavanones were stereoselectively hydroxylated at the α-position, by employing commercially available enantiopure oxaziridines, to afford the desired α-hydroxylated target molecules in good to exceptional stereoselectivities and in moderate to good chemical yields. A mechanistic rationale is presented to account for the stereoselectivities achieved. These in vitro results were tentatively related to the stereoselective biosynthesis of enantio-enriched dihydroflavonols while questions were raised about the authenticity of certain natural compounds.
通过使用市场上可买到的对映体纯噁嗪基里胺,对各种苯丙酮、色酮以及天然黄烷酮类似物的烯醇化物在α位进行立体选择性羟基化,以良好至特殊的立体选择性和中等至良好的化学收率得到所需的α-羟基化目标分子。本研究提出了一种机理原理来解释所实现的立体选择性。这些体外研究结果与对映体丰富的二氢黄酮醇的立体选择性生物合成初步相关,同时也对某些天然化合物的真实性提出了质疑。