159277-29-9Relevant academic research and scientific papers
DNA-targeted alkylating agents
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, (2008/06/13)
The invention relates to novel bis-benzimidazole compounds which have the ability to bind to the minor groove of DNA and to alkylate DNA, to methods of preparing the compounds, and the use of the compounds in the treatement of neoplastic disease.
DNA-directed alkylating agents. 6. Synthesis and antitumor activity of DNA minor groove-targeted aniline mustard analogues of pibenzimol (Hoechst 33258)
Gravatt,Baguley,Wilson,Denny
, p. 4338 - 4345 (2007/10/02)
A series of nitrogen mustard analogues of the DNA minor groove binding fluorophore pibenzimol (Hoechst 33258) have been synthesized and evaluated for antitumor activity. Conventional construction of the bisbenzimidazole ring system from the piperazinyl terminus, via two consecutive Pinner-type reactions, gave low yields of products contaminated with the 2-methyl analogue which proved difficult to separate. An alternative synthesis was developed, involving construction of the bisbenzimidazole from the mustard terminus, via Cu2+-promoted oxidative coupling of the mustard aldehydes with 3,4-diaminobenzonitrile to form the monobenzimidazoles, followed by a Pinner-type reaction and condensation with 4-(1-methyl-4-piperazinyl)-o- phenylenediamine. This process gives higher yields and pure products. The mustard analogues showed high hypersensitivity factors (IC50 AA8/IC50 UV4), typical of DNA alkylating agents. There was a large increase in cytotoxicity (85-fold) across the homologous series which cannot be explained entirely by changes in mustard reactivity and may be related to altering orientation of the mustard with respect to the DNA resulting in different patterns of alkylation. Pibenzimol itself (which has been evaluated clinically as an anticancer drug) was inactive against P388 in vivo using a single-dose protocol, but the short-chain mustard homologues were highly effective, eliciting a proportion of long-term survivors.
