Process for Synthesis of (3R,3'R)-Zeaxanthin and (3R,3'S;meso)-Zeaxanthin from (3R,3'R,6'R)-Lutein via (3R)-3',4'-Anhydrolutein
申请人:Khachik Frederick
公开号:US20090238933A1
公开(公告)日:2009-09-24
(3R, 3′R, 6′R)-Lutein and (3R, 3′R)-zeaxanthin are two dietary carotenoids that are present in most fruits and vegetables commonly consumed in the US and accumulate in the human plasma, major organs, and ocular tissues. Another stereoisomer of (3R, 3′R)-zeaxanthin that is not of dietary origin but is found in the human ocular tissues is (3R, 3′S; meso)-zeaxanthin. There is growing evidence that these carotenoids play an important role in the prevention of age-related macular degeneration (AMD) that is the leading cause of blindness in the U.S. and the Western World. In view of the potential therapeutic application of dietary lutein, (3R, 3′R)-zeaxanthin, and (3R, 3′S; meso)-zeaxanthin, the industrial production of these carotenoids is of considerable importance. The present invention provides a process for the partial synthesis of (3R, 3′R)-zeaxanthin and (3R, 3′S; meso)-zeaxanthin from a readily accessible dehydration product of (3R, 3′R, 6′R)-lutein, namely, (3R)-3′,4′-didehydro-β,β-caroten-3-ol [(3R)-3′,4′-anhydrolutein]. The process involves regioselective hydroboration of (3R)-3′,4′-anhydrolutein to a mixture of (3R, 3′R)-zeaxanthin and (3R, 3′S; meso)-zeaxanthin followed by separation of these carotenoids by enzyme-mediated acylation.
(3R, 3′R, 6′R)-叶黄素和(3R, 3′R)-玉米黄质是两种膳食类胡萝卜素,存在于美国常见的大多数水果和蔬菜中,并在人类血浆、主要器官和眼组织中积累。另一种立体异构体(3R, 3′S; meso)-玉米黄质虽非膳食来源,但在人眼组织中发现。越来越多的证据表明,这些类胡萝卜素在预防年龄相关性黄斑变性(AMD)方面发挥重要作用,该病是美国和西方世界导致失明的主要原因。鉴于膳食叶黄素、(3R, 3′R)-玉米黄质和(3R, 3′S; meso)-玉米黄质的潜在治疗应用,这些类胡萝卜素的工业生产具有相当重要的意义。本发明提供了一种从(3R, 3′R, 6′R)-叶黄素的易得脱水产物(3R)-3′,4′-去氢β,β-类胡萝卜烯-3-醇[(3R)-3′,4′-anhydrolutein]部分合成(3R, 3′R)-玉米黄质和(3R, 3′S; meso)-玉米黄质的方法。该过程涉及对(3R)-3′,4′-anhydrolutein的区域选择性氢硼化,得到(3R, 3′R)-玉米黄质和(3R, 3′S; meso)-玉米黄质的混合物,然后通过酶介导的酰化分离这些类胡萝卜素。