In 2005, Fenical et al. reported the isolation and charac­terization of cyclomarin D from Salinispora arenicola CNS-205. Interestingly, the same strain produced two other interesting metabolites, the cyclomarazines A and B, showing some anti­bacterial activity.

  • A. Isogai, J. Nakayama, S. Takayama, A. Kusai, A. Suzuki, Biosci. Biotechnol. Biochem.1992, 56, 1079–1085.

Biological testing of the synthesized compound revealed surprising results. The cyclomarazines A (R = Me) and B (R = H) displayed no antimicrobial activity against E. coli or S. aureus, in contrast to the reported activities for the isolated material. But the isolated cyclomarazines are described to be oils, while our synthesized compounds are obtained as white solids.

  • P. Barbie, U. Kazmaier, "Total synthesis of desoxycyclomarin C and the cyclomarazines A and B", Org. Biomol. Chem. 2016, 14, 6055−6064.