Crystal structure and conformational analysis of doxorubicin nitrate

Abstract

Crystal structure determination of doxorubicin nitrate, (DoxH)NO3, systematic name (7S,9S)-7-{[(2R,4S,5S,6S)-4-azaniumyl-5-hydroxy-6-methyloxan-2-yl]oxy}-6,9,11-trihydroxy-9-(2-hydroxyacetyl)-4-methoxy-8,10-dihydro-7H-tetracen-5,12-dione nitrate, shows two formula units present in the asymmetric unit. In the crystal lattice, hydrogen-bonded pairs of (DoxH+) cations and segregation of the aglycone and sugar moieties are observed. Inspection of molecular overlays reveals that the conformation of (DoxH)NO3resembles that of DNA-intercalated, but not of protein-docked (DoxH)+. The structure was refined as a two-component twin.