| Abstract
| - A previously synthesized unit of dolastatin 10 (1), dolaphenine (Doe, 3), was converted in foursteps to tripeptide 10. Subsequent condensation with carboxylic acid 11 (four steps from Meldrum'sacid) provided a practical synthesis of the cancer cell growth inhibitor dolastatin 18 (2, Dhex-(S)-Leu-(R)-N-Me-Phe-Doe). The synthesis of dolastatin 18 (2) confirmed the R stereochemistry of theN-Me-Phe unit as originally assigned and unusual among amino acid components of the sea hareDolabella auricularia. An X-ray crystal structure determination of dolastatin 18 was also completed.
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