R-基团相似性的比较

Comparison of the R-Group Similarity

介绍了对化学取代基 (R 基团 )进行相似性比较的工作 .每个R 基团主要依赖一些对反应影响较为明显 ,同时又便于计算的结构描述符来进行描述 ,例如电负性、氢键受体、氢键给体等参数 .由于与反应核心相距过远的环境对反应的影响较小 ,R 基团相似性比较对象 ,就由每个R 基团截取从它与母体连接的位点出发向外扩展 6层的子结构组成 .在确立了对R 基团描述和距离限制的基础上 ,提出了用一个 45维向量表示一个R 基团 ,并由化学结构的比较 ,转化为向量比较来实现R 基团相似性比较的方法 .采用这一方法 ,成功地对大量的R 基团进行了相似性的区分 。

This work is mainly concerned with the comparison of the similarities of the R-groups. Each R-group is based on several descriptors, such as electronegativity, hydrogen-bond acceptor, hydrogen-bond donor etc., which will affect reactions obviously and can be calculated conveniently. Since the environment with very long distance from the reaction core has relatively small effect on the reaction, the comparison partners of R-group can be regarded as some substructures that have through-bond of up to six from the point of substitution on the reaction core. This work proposed a method based on the description of R-group and the constraints of distance to compare the R-group similarities, which represented an R-group with a 45 dimensional vector and converted the comparison of chemical structures into the corresponding multiple vectors. Employing this method, we successfully distinguished a large number of R-group similarities, and realized the goal of predicating the similarity of unknown chemical compounds.