Self-association of doxorubicin and related compounds in aqueous solution.
The dimerization of doxorubicin, daunorubicin, and their 4-demethoxy, 4'-epi, and 4'-deoxy analogues was studied spectrophotometrically. Self-association was found to be influenced by buffer composition and ionic strength. Kd values were 1.3 X 10(4) and 2.3 X 10(4) M-1 for doxorubicin and daunorubicin, respectively, and ranged from 3.8 X 10(3) to 6.1 X 10(3) M-1 for the 4-demethoxy analogues. For 4'-epi- and 4'-deoxydoxorubicin, tetramerization has also been considered. On this basis, values of 2.0 X 10(4) and 2.2 X 10(4) M-1 were found, respectively, for the formation constant of the dimerization process. Stability of the dimeric species appears to be strongly influenced by substitution of the chromophore moiety.
D002626:Chemistry, Pharmaceutical; D003630:Daunorubicin / Q000031:analogs & derivatives / Q000032:analysis; D004317:Doxorubicin / Q000031:analogs & derivatives / Q000032:analysis; D015251:Epirubicin; D015255:Idarubicin; D012996:Solutions; D013053:Spectrophotometry / Q000379:methods
D012996:Solutions; D015251:Epirubicin; C041984:4'-deoxydaunomycin; C023481:4-demethoxydoxorubicin; C041983:4'-epidaunomycin; D004317:Doxorubicin; C030851:esorubicin; D015255:Idarubicin; D003630:Daunorubicin