Laboratório de Química Orgânica e Biocatálise, Instituto de Química de São Carlos, Universidade de São Paulo, Av. João Dagnone, 1100, Ed. Química Ambiental, Jd. Santa Angelina, São Carlos, São Paulo, 13563-120, Brazil. [Email]
This study describes the chemoselective hydrogenation reaction of halogenated 2'-hydroxychalcones by the marine-derived fungus Penicillium raistrickii CBMAI 931. Initially, 2'-hydroxychalcone was utilized as a model for the selection of the appropriate conditions to perform the biotransformation reactions. The best results were obtained using mycelia and filtered culture broth, and this condition was chosen for the biotransformation reaction of 2'-hydroxychalcones substituted with methoxy and halogen groups. Experiments performed with 2'-hydroxychalcones dissolved in 600 μL-DMSO were more effective than those performed using 300 μL-DMSO, once solubility of the compounds influenced conversion rate in the liquid medium. The halogenated 2'-hydroxy-dihydrochalcones were obtained in good conversions (78-99%) and moderate isolated yields (31-65%). All biotransformation reactions using the marine-derived fungus P. raistrickii CBMAI 931 showed regioselective and chemoselective control for the formation of 2'-hydroxy-dihydrochalcones.