A NEW DEVELOPMENT OF SYNTHETIC ORGANIC CHEMISTRY FOR BIOLOGICALLY ACTIVE NATURAL PRODUCTS OF MARINE ORIGINS

1)首次从一种叫Laurencia obtusa的红藻中合成了(+)-obtusenyne。此外，还完整地合成了两种异构体，这两种异构体的立体化学性质尚未确定。这些结果建立了这些化合物的绝对构型。2)为实现所提出的海洋源缩合环聚醚化合物的生物合成途径建立了合成路线。最后，以相应的聚环氧醇为模型，首先用内模法构造了缩合双环和三环醚化合物。3)建立了两种新的构造收敛双缩合环醚的有效方法。4)合成研究朝着全合成雪卡毒素的方向发展，雪卡毒素是雪卡毒素中毒的致病化合物。该合成策略基于收敛过程，先将四个片段分别合成，然后将它们组合成三个剩余的6-7元环醚体系（CD，GH，JK）。CD和JK环系的合成已经实现。5)首次从一种被认为是人类中毒的致病化合物的红藻Polycavernosa tsudai中完全合成了聚海绵体苷A。进一步阐明了结构与生物活性的关系。6)开展了以褐响尾鱼为源的致贝类中毒响尾鱼毒素的全合成研究。从而实现了通用bcdef环体系的一步构建。此外，通过模型实验建立了利用分子间Diels-Alder反应构建ag环体系的策略。7)开展了源于野贝（Patinopecten yessoensis）致贝类中毒pectenotoxin的全合成研究。结果，除C30位置外，所有片段都可以构建。少

1) The first total synthesis of (+)-obtusenyne isolated from a red alga, Laurencia obtusa, has been achieved. Furthermore, two isomers of obtusenyne, which had been isolated by None and undetermined stereochemically, were totally synthesized. These results led to establishment of the absolute configuration of these compounds.2) The synthetic route has been established toward realization of the proposed biosynthetic pathway for condensed cyclic polyether compounds of marine sources. Eventually, construction of the condensed bicyclic and tricyclic ether compounds were carried out firstly in endo-fashions starting from the corresponding polyepoxy alcohols as the models.3) Two new efficient methods have been established in order to construct convergently two-condensed cyclic ethers.4) The synthetic studies were developed toward the total synthesis of ciguatoxin which is the causative compound for ciguatera intoxication. The synthetic strategy was based on the convergent procedure to synthe … More size the four respective fragments and then to combine them constructing three residual 6-7-membered cyclic ether systems (CD,GH,JK). The synthesis of the CD and JK ring systems has been already achieved.5) The first total synthesis of polycavernoside A isolated from a red alga, Polycavernosa tsudai, regarding as a causative compound for human intoxication, has been achieved. Furthermore, the structure-biological activity relationship has been clarified.6) The study toward the total synthesis of pinnatoxins causing shell-fish poisoning originated from Pinna attenuata has been developed. Resultingly, the 1-step construction of the common BCDEF-ring system has been achieved. Furthermore, the strategy for construction of the AG-ring system has been established using an intermolecular Diels-Alder reaction by the model experiments.7) The study toward the total synthesis of pectenotoxins causing shell-fish poisoning originated from Patinopecten yessoensis has been developed. Resultingly, all the fragments were able to be constructed except the C30 position. Less