A fundamental relationship between hydrophobic properties and biological activity for the duocarmycin class of DNA-alkylating antitumor drugs: hydrophobic-binding-driven bonding.
Two systematic series of increasingly hydrophilic derivatives of duocarmycin SA that feature the incorporation of ethylene glycol units (n = 1-5) into the methoxy substituents of the trimethoxyindole subunit are described. These derivatives exhibit progressively increasing water solubility along with progressive decreases in cell growth inhibitory activity and DNA alkylation efficiency with the incremental ethylene glycol unit incorporations. Linear relationships of cLogP with -log IC50 for cell growth inhibition and -log AE (AE = cell-free DNA alkylation efficiency) were observed, with the cLogP values spanning the productive range of 2.5-0.49 and the -log IC50 values spanning the range of 11.2-6.4, representing IC50 values that vary by a factor of 10(5) (0.008 to 370 nM). The results quantify the fundamental role played by the hydrophobic character of the compound in the expression of the biological activity of members in this class (driving the intrinsically reversible DNA alkylation reaction) and define the stunning magnitude of its effect.
Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States.
Amanda L
AL
Wolfe
Katharine K
KK
Duncan
James P
JP
Lajiness
Kaicheng
K
Zhu
Adam S
AS
Duerfeldt
Dale L
DL
Boger
D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000737:chemistry / Q000494:pharmacology*; D001665:Binding Sites; D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry / Q000187:drug effects*; D000080890:Duocarmycins; D057927:Hydrophobic and Hydrophilic Interactions; D007211:Indoles / Q000737:chemistry / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D011758:Pyrroles / Q000737:chemistry / Q000494:pharmacology; D012995:Solubility; D021241:Spectrometry, Mass, Electrospray Ionization
D018906:Antineoplastic Agents, Alkylating; D000080890:Duocarmycins; D007211:Indoles; D011758:Pyrroles; C066098:duocarmycin SA; D004247:DNA