The experimental determination of formation constant for interaction of two water soluble phthalocyanines,Cobalt (II) 4,4',4",4'"-tetrasulpho phthalocyanine (CoTsPc ) and Manganese(II) 4,4',4",4"-tetrasulphophthalocyanine (MnTsPc ) , with calf thymus DNA have been studied by UV-Vis spectrophotometric methodat lrnM phosphate buffer , pH 7.4 and at 5 different temperatures 20,25,30,35 and 400CC ....

In depth interaction studies between calf thymus deoxyribonucleic acid (CT-DNA) and a series of four structurally relative palladium(II) complexes [Pd(en)(HB)](NO3)2 (a-d), where en is ethylenediamine and heterocyclic base (HB) is 2,2'-bipyridine (bpy, a); 1,10-phenanthroline (phen, b); dipyridoquinoxaline (dpq, c) and dipyridophenazine (dppz, d) (Figure 1), were performed. These studies have b...

The assembly of double-stranded (ds) DNA nanocircles both by hybridization with branched oligodeoxynucleotides (ODNs) and by intercalation was analyzed by atomic force microscopy (AFM). Branched ODNs ligated to single-stranded (ss) gap regions of dsDNA nanocircles led to defined, dumbbell-shaped architectures. ODNs containing an aromatic intercalator yielded oligomeric aggregates.

The carcinogen, 7r,8t-dihydroxy-9t,10t-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene, and a number of its noncarcinogenic derivatives form a reversible physical complex with DNA in vitro. The absorbance spectrum of the hydrocarbon in the complex shifts approximately 10 nm to the red. Fluorescence from the physically bound hydrocarbon is significantly quenched, and binding levels are decreased by the ...

The interaction between 4',6-diamidino-2-phenylindole (DAPI) and the DNA oligomer [d(CGACGTCG)]2 has been investigated by proton one- and two-dimensional NMR spectroscopy in solution. Compared with the minor groove binding of the drug to [d(GCGATCGC)]2, previously studied by NMR spectroscopy, the interaction of DAPI with [d(CGACGTCG)]2 appears markedly different and gives results typical of a b...

A new cytotoxic acridine alkaloid that exhibited antitumor activity in vivo was isolated from a marine Dercitus species sponge collected at a depth of 160 m in the Bahamas. This violet alkaloid, designated dercitin, inhibited the proliferation of cultured murine and human leukemia, lung, and colon tumor cells at MMconcentrations (K .„ values of 63-150 MM) and prolonged the life of mice bearin...

The thermodynamic parameters for the intercalative interaction of structurally related well known intercalators, 9-aminoacridine (9AA) and proflavine (PF) were determined by means of fluorescence quenching study. The fluorescence intensity of 9AA decreased upon intercalation to DNA, poly[d(A-T)2] and poly[d(G-C)2]. A van’t Hoff plot was constructed from the temperature-dependence of slope of th...

In many diseases such as cancer, simultaneous use of two or more pharmacologically active agents will be more effective and have fewer side effects. In this study a new palladium(II) complex with formula of [Pd(phen)(py-dtc)]NO3 (where is phen 1,10-phenanthroline and py-dtc is n-propyldithiocarbamate), was synthesized. The cytotoxic activity of this complex was tested against leukemia K562 cell...

Short Cbmmunieation Proposed Two-molecule Intercalation between Neighboring Base Pairs of DNA Hideyuki ToMosAKA,t Kentaro ANzAi,* and Saburo OMATA Department oj'Biosystem Science, Graduate School ofScience and Tlechnology, fViigata UhiversitJ,, igarashi, Niigata, Niigata 950-21, Jopan 'Department ofC7iemistry, Rietilty ofSeienee, Seience Uhiversity of 7bkyo, Kdgurazaka, Shinjuku-ku, 7bkyo i62, ...

The interaction specificity of salmon sperm DNA with 2-hydroxyethanethionlato(2,2',2''-terpyridine)platinum(II),PtTS has been studied. The results of 1H and 13C nuclear magnetic resonance, flow dichroism and circular dichroism studies are found to be consistent with an intercalation mode of binding as has been proposed earlier by lippard and coworkers.