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全合成的意义是什么？**
最近写了一篇长文《 关于维生素B12全合成的详细解析》，就来这里投一下。

相信看完之后，你就明白全合成的意义了。

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谨以此文，纪念维生素B12被人类发现90周年。**

注：如果本文中有任何错误或疏漏，请务必联系作者或在评论中写出。不胜感谢！**

## 1.前情提要

维生素B12**（\text{Vitamin B12}，又名 钴胺素**，缩写 \text{VB12}），这种物质（其实严格来说是一类物质）如今早已家喻户晓。作为唯一一种 含有金属元素的维生素**，其中心的 ![\ce{Co} ... ⌘ [Read more](http://www.zhihu.com/question/29971756/answer/3595718726?utm_campaign=rss&utm_medium=rss&utm_source=rss&utm_content=title)