Fred E. Boettner

Isolation of dolastatins 10–15 from the marine mollusc dolabella auricularia

Abstract A twenty year pursuit of the cell growth inhibitory and antineoplastic constituents of the Western Indian Ocean (Mauritius) sea hare Dolabella auricularia has resulted in the discovery of fifteen structurally unique peptide, cyclopeptide, depsipeptide, and cyclodepsipeptide type-substances designated dolastatins 1–15. Solution of the difficult isolation problems leading to discovery of dolastatins 10–15 in 10−6 to 10−7% yields required 1,600 kg of Dolabella aurlcularia. To date, this represents the largest scale separation of sea hare components. Of these dolastatin 10 (4) has displayed unprecedented potency in experimental antineoplastic and tubulin assembly systems. Dolastatin 15 (9), and to a lesser extent dolastatin 14 (8) were also found to exhibit unusually strong antineoplastic activity. Both dolastatina 10 and 15 are in advanced preclinical development. Details of the isolation strategies and structural summaries for dolastatins 10–15 have been recorded. Intensive Study of the cell growth inhibition and antineoplastic constituents of the sea hare Dolabella auricularia provided the structurally unique peptides designated dolastatins 1-15.

Isolation and structure of the powerful human cancer cell growth inhibitors spongistatins 4 and 5 from an African Spirastrella spinispirulifera(porifera)

The Southwest Indian Ocean marine sponge Spirastrella spinispirulifera has been found to contain (in 10–7% yields) two extraordinarily potent (Gl50ca. 10–8µg ml–1) human cancer cell line inhibitors designated spongistatins 4 1d and 5 2.