Isolation of bio active natural compounds, mainly , anti bacterial , anti viral and/or cytotoxic compounds from plants and mainly marine organisms ( soft corals, sponges and tunicates ). The compounds belong to the various bio-synthetic groups , namely , terpenoids , polyketides and nitrogen containing compounds ( alkaloids ? ) . The structure elucidation was achieved by spectroscopic means , mainly , 1D- and 2D-NMR spectra. As well as MS and chemical transformations. The marine organisms were collected from shallow to 50 m deep waters of the Red Sea, the East coasts of Africa, and west coast of Madagascar. Based on the many novel structures , congeners were synthesized , that is , diterpene analogs and latrunculins, as well as total synthesis of eilatin , endiamino- and thioenamino cyclic peptides . Work was also done on Israel Negev plants.