Kinetic and Equilibrium Binding Studies of a Series of Intercalating Agents That Bind by Threading a Sidechain through the DNA Helix. In: Pullman B, Jortner J, editors. Molecular Basis of Specificity in Nucleic Acid-Drug Interactions. Dordrecht: Springer Netherlands; 1990. pp. 191-206. [DOI: 10.1007/978-94-011-3728-7_14]

Synthesis, antitumor cytotoxicity, and DNA-binding of novel N-5,2-di(omega-aminoalkyl)-2,6-dihydropyrazolo[3,4,5-kl]acridine-5-carboxamides

A series of DNA-binding potential antitumor agents bearing a cationic carboxamide side chain attached in position peri to an electron-withdrawing atom, N-5,2-di(omega-aminoalkyl)-2,6-dihydropyrazolo[3,4,5-kl]acridine-5-carboxamides, has been prepared by reaction of the appropriate 1-chloro-9-oxo-9,10-dihydro-4-acridinecarboxamides with the suitable (omega-aminoalkyl)hydrazine. The noncovalent DNA-binding properties of these compounds have been examined using a fluorometric technique. In vitro cytotoxic potency of these derivatives toward the human colon adenocarcinoma cell line (HT29) is described and compared to that of reference drugs. Structure-activity relationships are discussed. Two highly DNA-affinic and potent cytotoxic compounds, 4m,o, have been identified as new leads in the antitumor strategies.

Synthesis and structure-activity relationships of potential anticancer agents: alkylcarbamates of 3-(9-acridinylamino)-5-hydroxymethylaniline

A series of potential 9-anilinoacridine antitumor agents, 3-(9-acridinylamino)-5-hydroxymethylaniline (AHMA) derivatives with monosubstituent at C4' and disubstituents at C4' and C5' of the acridine ring and their alkylcarbamates, were synthesized for evaluation of their antitumor activity. A structure-activity relationship (SAR) study showed that the AHMA-alkylcarbamates were more potent than their corresponding parent AHMA compounds. In addition, the cytotoxicity of the AHMA-alkylcarbamate decreased with increasing length and size of the alkyl function. Among these compounds, AHMA-ethylcarbamate (18) and 4'-methyl-5'-dimethylaminoethylcarboxamido-AHMA-ethylcarb amate (34) possess potent cytotoxicity on the inhibition of human leukemic HL-60 cell growth in culture. Further in vivo studies of these compounds displayed significant anticancer therapeutic effects in mice bearing sarcoma 180, Lewis lung carcinoma, and P388 leukemia.

Use of electric linear dichroism and competition experiments with intercalating drugs to investigate the mode of binding of Hoechst 33258, berenil and DAPI to GC sequences

The drugs Hoechst 33258, berenil and DAPI bind preferentially to the minor groove of AT sequences in DNA. Despite a strong selectivity for AT sites, they can interact with GC sequences by a mechanism which remains so far controversial. The 2-amino group of guanosine represents a steric hindrance to the entry of the drugs in the minor groove of GC sequences. Intercalation and major groove binding to GC sites of GC-rich DNA and polynucleotides have been proposed for these drugs. To investigate further the mode of binding of Hoechst 33258, berenil and DAPI to GC sequences, we studied by electric linear dichroism the mutual interference in the DNA binding reaction between these compounds and a classical intercalator, proflavine, or a DNA-threading intercalating drug, the amsacrine-4-carboxamide derivative SN16713. The results of the competition experiments show that the two acridine intercalators markedly affect the binding of Hoechst 33258, berenil and DAPI to GC polynucleotides but not to DNA containing AT/GC mixed sequences such as calf thymus DNA. Proflavine and SN16713 exert dissimilar effects on the binding of Hoechst 33258, berenil and DAPI to GC sites. The structural changes in DNA induced upon intercalation of the acridine drugs into GC sites are not identically perceived by the test compounds. The electric linear dichroism data support the hypothesis that Hoechst 33258, berenil and DAPI interact with GC sites via a non-classical intercalation process.