Anionic polyhedral boron clusters conjugates with 7-diethylamino-4-hydroxycoumarin. Synthesis and lipophilicity determination.

A series of water-soluble conjugates of 7-diethylamino-4-hydroxycoumarin with four different anionic polyhedral boron clusters was synthesized. The distribution coefficients (log D 7.4) as a measure of the ability to pass through the cell membrane for novel compounds were determined via a shake-flask methodology in n-octanol/aqueous (pH 7.4) buffer solution system. For two closo -dodecaborate modifications log D 7.4 displayed negative lipophilicity values. Conjugates of metallacarboranes containing Co and Fe as long as two 7,8-dicarba- nido -undecaborate coumarin anions were found to have appropriate lipophilicity for medicinal applications. • Novel anionic coumarin conjugates with several boron clusters were synthesized. • The first iron bis(1,2-dicarbollide) conjugate with coumarin is described. • Distribution coefficients (log D7.4) of prepared compounds were determined. • Some conjugates were found to have appropriate lipophilicity for medicinal use. [ABSTRACT FROM AUTHOR]