Biological activity of 4-hydroxy-5-formylbenzoic acid derivatives

A group of thirty 4-hydroxy-5-formylbenzoic acid derivatives of general formula: (formula; see text) where (formula; see text) have been prepared and characterized in an attempt to make available for testing a representative selection of hitherto undescribed hydroxyformylbenzoic acid derivatives. The products, which are listed in Table I, with pertinent data, have been obtained in satisfactory yield and in a good state of purity. The prepared compounds have been tested for "in vitro" activity against three fungi (A. niger, C. albicans, S. cerevisiae), six Gram- bacteria (E. coli Bb, S. typhi, S. infantis, S. paratyphi A, B. melitensis, P. mirabilis) and four Gram+ bacteria (M. paratuberculosis ATCC 607; S. epidermidis, B. subtilis, B. anthracis), by the agar diffusion method (Kirby-Bauer modified). In general, the results of the tests indicated that most of the compounds: a) didn't exhibit antifungal activity "in vitro"; b) had little activity on Gram- bacteria; showed inhibitory activity toward Gram+ species, in particular toward M. paratuberculosis. Other activities of pharmaceutical interest will be tested; the screening program includes tests for cardiac activity. The results of these studies will be published as soon as they are complete.