Assembly of DNA recognition elements on an octahedral rhodium intercalator: predictive recognition of 5'-TGCA-3' by Δ-[Rh[(R,R)-Me_2trien]phi]^(3+)

Here we explore the de novo design of rhodium intercalators for predictive four base pair recognition of duplex DNA. Complexes have been constructed which, like DNA-binding proteins, pose several functionalities for site-specific noncovalent interaction with DNA. Octahedral rhodium intercalators are particularly useful in this design since (i) the octahedral coordination specifies the stereochemistry of ligand functionalities and (ii) the intercalating ligands orients these functionalities with respect to the DNA major groove

Metallointercalators: structure of rac-bis(ethylenediamine)(9,10-phenanthrenequinone diimine)rhodium(III) tribromide trihydrate

Bis(ethylenediamine)(phenanthrenequinone diimine)rhodium(III) tribromide trihydrate has a nearly planar phenanthrenequinone diimine ligand and two ordered ethylenediamine ligands, giving a distorted octahedral coordination to the compound. The N-Rh-N angles range from 77.1 (6) to 96.5°, with the largest deviations from 90° associated with the N atoms of the phenanthrenequinone diimine ligand. The two Rh-N distances involving these N atoms are 0.05 Å shorter than Rh-N distances to ethylenediamine ligands; other distances and angles are within normal ranges