Two alkaloids of pseudopteroxazole and ileabethoxazole, isolated from sea whip Pseudopterogorgia elisabethae, have significant antimicrobial activity against pathogen of tuberculosis: Mycobacterium tuberculosis. These two alkaloids possess similar tetracyclic skeleton, which containing four stereocenters, a fully substituted aromatic ring and an uncommon benzoxazole unit in natural products. Significant antimicrobial activity and special molecular structures attracted extensive attentions to synthetic study on pseudopteroxazole and ileabethoxazole. The progress in the total synthesis of these two alkaloids is reviewed. Keywords Mycobacterium tuberculosis; alkaloid; pseudopteroxazole; ileabethoxazole; total synthesis 结核病(Tuberculosis, TB)是由其病原体--结核分 枝杆菌(Mycobacterium tuberculosis)经空气传播而引起 的传染病. 由于结核分枝杆菌对治疗药物不断突出的耐 药性问题, 使得结核病对人类健康的威胁日渐严重. 对 结核病的研究已成为一个非常重要和活跃的领域 [1] . 在 治疗药物研发中, 具有抗结核分枝杆菌活性的天然产物 是筛选优秀先导化合物的一个重要来源 [2][3][4] .Pseudopteroxazole (1) [3] 和 ileabethoxazole (2) [4] 是 Rodriguez 课题组从分别生存于西印度洋和加勒比海中 的海鞭 Pseudopterogorgia elisabethae 中分离得到的两种 海洋生物碱, 生理活性研究表明两种生物碱对结核分枝 杆菌都具有良好的抗菌活性. 两者在分子结构上也颇为 相似(图 1), 四环基本骨架中都具有天然产物中少有的 苯并噁唑单元(D 环)和一个全取代苯环(A 环), 各自拥有 的四个立体中心中有三个完全相同. 不同之处在于 C 环 的大小和 C(1)的立体构型以及取代基的不同. 良好的抗结核分枝杆菌活性和独特的分子结构使 得对 1 和 2 的全合成研究得到了广泛的关注.

Accelerating the construction of livestock powerhouses is of great significance to better enhance the ability to guarantee the supply of livestock products and improve the quality, efficiency and competitiveness of the livestock industry. This study constructed an evaluation index system to assess the level of China’s livestock powerhouse and then performed an in-depth analysis of the issues and challenges facing the construction of livestock powerhouses. The research results showed that the level of China’s livestock powerhouse ranked 5th in the world, and the livestock industry was transitioning from being a large livestock country to a powerhouse, while there was still a large gap in terms of reaching the goal of constructing livestock powerhouses. There were significant differences in the level of livestock powerhouses across different livestock industries; the layer industry was the world leader in China, whereas the pig, sheep and goat, and broiler industries were stronger, while the beef cattle and dairy industries were weaker. There are still many challenges to accelerating the construction of livestock powerhouses in terms of supply security, scientific and technological support, operation systems, industry and supply chain resilience, international trade, policy support, etc. It is recommended to improve the institutional mechanism for the construction of livestock powerhouses, promote a high level of self-reliance and self-improvement in livestock science and technology, build a modern livestock operation system, enhance the resilience and security level of the industrial and supply chain, and consolidate and expand international trade and cooperation.