C-13核磁数据库

碳－13核磁共振波谱数据库系统始建于1982年,它是国内第一个比较大型的碳-13 NMR数据库系统，主要用于有机化合物结构的自动解析。数据类型包括有机化合物的诸种有关信息：化合物名称，分子式，分子量，化学位移和多重性，谱图，结构信息，谱图的来源即参考文献，以及相关的实验条件，等等。检索中，对于化合物名称，分子式，分子量等，允许每项单独检索，同时也允许两项或多项联合检索。在联合检索中，必须同时满足所给定的多项条件方可被检索。谱图信息如化学位移检索是碳13NMR数据库检索中的重要内容。系统允许单峰检索，同时允许多个峰值一起即相似性检索。单峰检索要求使用者对碳13NMR谱有较多的了解，这样才能够选取较“特征”的峰，以使检索高效。若选取的峰不太“特征”，则库中的“响应”将会过多，搜索速度慢且结果可能较差。谱图的相似性检索是谱图类检索中的最重要的功能，因为论数据库有多大，它总会不包含新合成的化合物，在库中没有完全相同的化合物时，借助相似性检索，则可得到与检索化合物相似的化合物（以相似度大小为序给出）。

The Carbon-13 Nuclear Magnetic Resonance (¹³C NMR) Spectroscopy Database System was established in 1982. It was the first large-scale dedicated ¹³C NMR database system in China, primarily used for the automatic elucidation of organic compound structures. The database contains various types of information related to organic compounds, including compound names, molecular formulas, molecular weights, chemical shifts and multiplicities, spectral data, structural information, spectral sources (i.e., references), and related experimental conditions, among others. For retrieval operations, single-item searches are allowed for fields such as compound names, molecular formulas, and molecular weights, while combined searches of two or more criteria are also supported. In combined searches, only compounds that meet all specified conditions will be returned as matching hits. Spectral information retrieval, such as chemical shift search, is a core component of ¹³C NMR database retrieval. The system supports both single-peak search and multi-peak joint similarity search. Single-peak search requires users to have a solid grasp of ¹³C NMR spectra, so that they can select relatively "characteristic" peaks to ensure efficient retrieval. If non-characteristic peaks are selected, the database will return excessive hits, leading to slow search speeds and suboptimal results. Spectrum similarity search is the most critical function in spectral retrieval, as no database, regardless of its scale, will cover all newly synthesized compounds. When no exact matching compound exists in the database, similarity search can retrieve compounds structurally similar to the query compound, with results sorted by their similarity scores in descending order.

搜集汇总

背景与挑战

背景概述

C-13核磁数据库是国内首个大型碳-13 NMR数据库系统，始建于1982年，主要用于有机化合物结构的自动解析，包含8万条记录，数据量达2330MB。该数据库支持化合物名称、分子式、分子量等单项或联合检索，以及化学位移的单峰和相似性检索，适用于有机化合物结构分析。