Synthesis of 4-Nitrophenyl β-d-galactofuranoside: A Useful Substrate for β-d-Galactofuranosidases Studies

Abstract

Beta-D-Galactofuranosyl units (Beta-D-Galf) are constituents of microorganisms, some of them pathogenic, such as Mycobacteria, the trypanosomatids Trypanosoma cruzi and Leishmania1 and fungi like Aspergillus fumigatus.2 Since Galf has never been found in mammals, its biosynthesis and metabolism are good targets for chemotherapeutic strategies. In some species the degradation of Galf containing glycoconjugates is promoted by extracellular beta-D-galactofuranosidases. For example, Penicillium and Apergillius species,3 Helminthosporium sacchari4 and Trichoderma harzianum5 produce exo beta-D-galactofuranosidases (EC 3.2.1.146).First studies of beta-D-galactofuranosidases involved the use of methyl Beta-D-galactofuranoside as substrate and the tedious measurement of the reducing sugar released by the enzyme.4,6 The availability of the chromogenic substrate 4-nitrophenyl beta-D-galactofuranoside (3)