DIONES, SULFOXIDES, AND SULFONES FROM THE AEROBIC COMETABOLISM OF METHYLBENZOTHIOPHENES BY PSEUDOMONAS STRAIN BT1

Six methyl-substituted benzothiophenes were synthesized and used as substrates for Pseudomonas strain BT1. These compounds would not support growth but were cometabolized when the culture was grown on 1-methylnaphthalene or glucose. Sulfur-containing metabolites were identified by GC-MS and GC-FTIR and, when possible, by comparison with authentic standards. 2,3-Diones were the metabolites from 4-methylbenzothiophene, 5-methylbenzothiophene, and 6-methylbenzothiophene. Sulfoxides were the major products from 2-methylbenzothiophene and 2,3-dimethylbenzothiophene. Sulfones were also detected as metabolites of the latter two compounds. Cometabolism of 7-methylbenzothiophene yielded the corresponding 2,3-dione, sulfoxide, sulfone, and several other unidentified compounds. Thus, the nature of the metabolites from these methylbenzothiophenes was dependent on the position of the methyl substitution.