RESUMO
Novel hybrid molecules between benzenesulfonamides and active antimicrobial 2-amino-benzo[d]isothiazol-3-ones were synthesized and characterised and their in vitro antimicrobial activity was evaluated by the minimal inhibitory concentration (MIC). The compounds exhibit moderate antibacterial properties against gram-positive bacteria (MIC 6-100 microg ml(-1)) such as several bacilli, staphylococci and streptococci, including methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis strains, while no inhibition of gram-negative Escherichia coli is detected up to the concentration of 100 microg ml(-1). Synergistic inhibitory activity occurs when sulfanilamides 4a and 4c are tested in combination with trimethoprim against S. aureus. Concerning antifungal properties, only compound 4c is able to inhibit the growth of Saccharomyces cerevisiae and Cryptococcus neoformans yeasts and several dermatophytes. Structure-activity relationships are discussed.
Assuntos
Antibacterianos/síntese química , Sulfonamidas/química , Tiazóis/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Saccharomyces cerevisiae/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacologia , BenzenossulfonamidasRESUMO
The phosphorus ylide obtained from the reaction between 2-aminobenzo[d]isothiazol-3-one and dimethyl acetylenedicarboxylate in the presence of triphenylphosphine undergoes a smooth intramolecular Wittig-type reaction to produce, in a one-pot reaction, 3-H-benzo[d]pyrazolo[1,5-b]isothiazole-2,3a-dicarboxylic acid dimethyl ester, a novel functionalized heterocyclic compound.
