1. Research Group of Peptide Chemistry, Eötvös Loránd University (ELTE), Hungarian Academy of Sciences, Budapest 112, P.O. Box 32, H-1518, Hungary, Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Budapest, Gellért tér 4, H-1521 Hungary, Research Group for Alkaloid Chemistry, Hungarian Academy of Sciences, University of Technology and Economics, Budapest, Gellért tér 4, H-1521 Hungary, Institute of Enzymology, Biological Research Center, Hungarian Academy of...