錝,5″S)-2-{3′-Methoxy-2′-propoxy-5′-[5″-(3,4,5-trimethoxyphenyl)tetrahydrofuran-2″-yl] phenylsulfonyl}ethanol(MK-287) which was potent PAF antagonist, was enantioselectively synthesized in eight steps by a...錝,5″S)-2-{3′-Methoxy-2′-propoxy-5′-[5″-(3,4,5-trimethoxyphenyl)tetrahydrofuran-2″-yl] phenylsulfonyl}ethanol(MK-287) which was potent PAF antagonist, was enantioselectively synthesized in eight steps by addition, oxidation, hot decomposition, hydrogenation and so on from (-)-4,10-dioxatricyclo-[5.2.1.0 2,6]-decene-3-ole(1). Asymmetry was introduced using the nucleophilic addition of the triisopropoxytitanium to the lactol 1. The second asymmetric center was installed by a highly stereocontrolled acid-assisted reduction with sodium cyanoborohydride of the hemiketal formed. The product MK-287 was optically pure.展开更多
文摘錝,5″S)-2-{3′-Methoxy-2′-propoxy-5′-[5″-(3,4,5-trimethoxyphenyl)tetrahydrofuran-2″-yl] phenylsulfonyl}ethanol(MK-287) which was potent PAF antagonist, was enantioselectively synthesized in eight steps by addition, oxidation, hot decomposition, hydrogenation and so on from (-)-4,10-dioxatricyclo-[5.2.1.0 2,6]-decene-3-ole(1). Asymmetry was introduced using the nucleophilic addition of the triisopropoxytitanium to the lactol 1. The second asymmetric center was installed by a highly stereocontrolled acid-assisted reduction with sodium cyanoborohydride of the hemiketal formed. The product MK-287 was optically pure.