The application of FEL-EXPERT system in the interpretation of boron compounds toxicity
The influence of substructural features on boron compounds toxicity (LD50, mice, i.p.) has been studied by FEL-EXPERT system developed at the Czech Technical University of Prague. A set of 108 compounds containing one or two boron atoms in their molecule has been arbitrarily divided into three classes: the compounds with a high toxicity (LD50 < 100 mg/kg), with a medium toxicity (100 mg/kg ⪬ LD50 < 1 000 mg/kg) and with a low toxicity (LD50 ≥ 1 000 mg/kg). The compounds have been represented by 70 substructural fragments, 27 of them being "central substructures" containing boron atom(s). The inference net consists of 118 nodes (74 of the Bayesian type), 362 production rules and 74 context links. The total classification correctness has been 98%. As a case-study, the classification of p-tolylboronic acid (LD50 = 520 mg/kg) and 4-carboxyphenylboronic acid (LD50 = 3 838 mg/kg) has been discussed.