Fungal and bacterial regioselective hydroxylation of pyrimidine heterocycles

The bacterium Rhodococcus erythropolis is employed to hydroxylate the anxiolytic lesopitron, and this bacterium, together with Agrobacterium sp. and the fungus Beauveria bassiana, are used to extend the field of hydroxylation of heteroaromatic compounds to a series of unexplored pyrimidines. Of all the substrates investigated, only the carbamate 11a is regioselectively hydroxylated by B. bassiana at the C-5 position of the pyrimidine ring; in contrast, the bacteria are able to regioselectively oxidize, when free, the C-2 and/or C-4 positions of the pyrimidine moiety of all the substrates 1a - 12a, up to a maximum of two oxidations. (C) 1997 Elsevier Science Ltd.