Three branched monomers 1 ~ 3, possessing 3 - fold symmetry and branches emanating from a tetrahedral carbon branch point, were utilized as the key building block in the dendrimer syntheses.

目标化合物以甘油、硝基甲烷为三方向起始核心，以从季碳原子三倍对称分散的化合物1～3为分支侧链。

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It can fold in on itself to become a completely sealed concrete block, preventing any of the undead from getting in.

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