Toxicology Research Today is a free monthly online journal that collates and summarizes the latest research about Toxicology, including details on forensic toxicology, carcinogenicity, assays.

Synthesis and comparative toxicology of a series of polyhedral borane anion-substituted tetraphenyl porphyrins.

Koo MS, Ozawa T, Santos RA, Lamborn KR, Bollen AW, Deen DF, Kahl SB

Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California 94143, USA.

Three structurally similar tetraphenylporphyrins bearing polyhedral borane anions have been synthesized and their toxicological profiles obtained in rats. These conjugates were found to have quite different acute toxicities as manifested at the maximum tolerated dose (MTD). When given at the MTD and observed over 28 days, the most acutely toxic porphyrin was found to be devoid of toxicity, as measured by blood chemistry panels. The remaining two less acutely toxic compounds both elicited significant changes, characterized by moderate to severe thrombocytopenia, failure to gain weight normally and changes in liver enzymes indicative of mild hepatotoxicity. All toxic effects were transient, with platelets rebounding to above normal levels at day 28. We conclude that thrombocytopenia is the dose limiting toxicity for boronated porphyrins in mammals and suggest that these effects may be due to the porphyrin, not the borane or carborane.

Published 15 February 2007 in J Med Chem, 50(4): 820-7.
Full-text of this article is available online (may require subscription).

© 2005-2008 Toxicology Research Today. All Rights Reserved.