Synthetk Studies on Multi Sorts of Biologically Active Cormpounds Using Nitrones Related to Amino Acids and Sugars

(1)探索了从糖等疝缩醛合成具有多氧官能团的环状硝酮的方法。因此，硝酮是通过 ω-甲磺氧基-O-叔丁基二苯基甲硅烷基肟的 TBAT 介导的脱甲硅烷基化环化来制备的，该肟可以通过用 O-叔丁基二苯基甲硅烷基羟胺和甲磺酰氯连续处理从糖衍生物容易地制备。作为该方法的应用，以受保护的L-木糖为原料，实际实现了党参碱、风信子碱A_1和风信子碱A_2的简捷合成。(2)(S)-苯基甘氨醇衍生的环硝酮在MgBr_2OEt_2存在下与烯丙醇反应，立体选择性地生成环加合物。该反应应用于莫纳甜（天然甜味剂）和番茄酸的合成。与烯丙醇的环加成相反，环状硝酮与α-取代丙烯酸酯在不存在 MgBr_2·OEt_2 的情况下反应，得到具有相反 C4 立体化学性质的环加合物。该反应用于4-表莫纳甜的合成。(3)首次合成了(-)-funebrine和(-)-funebral。该合成的特点是由乙醛酸甲酯与古洛糖衍生的肟依次形成硝酮，与(E)-巴豆醇进行酯交换，以及分子内环加成。主要环加合物很容易合成为(-)-funebrine和(-)-funebral的关键合成中间体氨基内酯。(4)合成尼古丁的主要代谢物(3'R,5'S)-3'-羟基可替宁，C-(3-吡啶基)硝酮与(2R)-和(2R)-检查了(2S)-N-(丙烯酰基)冰片烷-10,2-磺内酰胺{(2R)-和(2S)-磺内酰胺]。其中，L-古洛糖衍生的硝酮与(2S)-磺内酰胺进行立体选择性环加成反应，得到环加成物，进而得到(3'R,5'S)-3'-羟基烟替宁。(5)综述了Diets-Alder反应和硝酮环加成反应等代表性的周环反应在杂环化合物合成中的应用。较少的

(1)A method for the synthesis cyclic nitrones having multi-oxygen functionalities from herniacetals such as sugars was explored. Thus, the nitrones were prepared by TBAT-mediated desilylative cyclization of ω-mesyloxy-O-tert-butyldiphenylsilyloximes, readily prepared from sugar derivatives by a consecutive treatment with O-tert-butyldiphenylsilylhydroxylamine and with mesyl chloride. As an application of this method, concise synthes of codonopsine, hyacinthacine A_1, and hyacinthacine A_2 were reality accomplished from the cyclic nitrone, which was obtained from protected L-xylose.(2)A cyclic nitrone derived from (S)-phenylglycinol reacted with allyl alcohols in the presence of MgBr_2OEt_2 to give cycloadducts stereoselectively. The reaction was applied to syntheses of monatin (a natural sweetener) and lycoperdic acid. In contrast to cycloaddition with allyl alcohols, reactions of the cyclic nitrone with a-substituted acrylates in the absence of MgBr_2・OEt_2 gave cycloadducts having op … More posite C4-stcreochemistries. The reaction was used for the synthesis of 4-epi-monatin.(3)The first syntheses of (-)-funebrine and (-)-funebral were achieved. The syntheses feature sequential formation of the nitrone from methyl glyoxylate with a gulose-derived oxime, transesterification with (E)-crotyl alcohol, and intramolecular cycloaddition. The major cycloadduct was readily elaborated to amino lactone, the key synthetic intermediate of (-)-funebrine and (-)-funebral.(4)To synthesize (3'R,5'S)-3'-hydroxycotinine, the main metabolite of nicotine, cycloaddition of C-(3-pyridyl)nitrones with (2R)-and (2S)-N-(acryloyl)bornane-10,2-sultam {(2R)-and (2S)-sultam] was examined. Among them, L-gulose-derived nitrone underwent stereoselective cycloaddition with (2S)-sultam to afford the cycloadduct, which was elaborated to (3'R,5'S)-3'-hydroxyeotinine.(5)Applications of Diets-Alder reactions and cycloaddition of nitrones, representative peri-cyclic reactions to synthesis of heterocyclic compounds were reviewed. Less