[1] Hebrew Univ Jerusalem, Hadassah Med Sch, Sch Pharm, Dept Med Chem, IL-91120 Jerusalem, Israel
[2] Med Univ, Dept Biochem & Chem, Pleven 5800, Bulgaria
[3] Bulgarian Acad Sci, Inst Organ Chem, Ctr Phytochem, BU-1113 Sofia, Bulgaria
[4] David R Bloom Ctr Pharm, Jerusalem, Israel