1. Department of Chemistry, University of Toronto, ON, Canada M5S 3H6, Department of Chemistry and Chemical Informatics, Faculty of Education, University of Szeged, Szeged, Boldogasszony sgt. 6, Hungary 6725, and Protein Chemistry Research Group, Hungarian Academy of Sciences, University of Szeged, Dóm tér 8, Szeged, Hungary 6720