DNA Binding Constants Research Articles

Elucidation of DNA binding properties of transition metal ion complexes of curcumin: An In Vitro study

Introduction: The present work aims to synthesize, characterize, and DNA binding properties of copper, nickel, zinc, and iron complexes of a well-known polyphenol drug curcumin. The metal ion complexes of curcumin's synthesized transition metal ion complexes were characterized by UV-vis spectroscopy and FTIR. Method: The complexation of curcumin with transition metal ion complexes changes the color of the curcumin based on the metal incorporated. Moreover, the shift in the absorption maxima of curcumin metal ion complexes may confirm the formation of coordination complexes. Then, FTIR results indicated that the coordination of curcumin with metal ions in the ketone group of curcumin confirms the formation of 1:2 (M: L) complexes. Results: Then, we evaluated the DNA binding properties of synthesized metal ion complexes of curcumin using electronic absorption spectra and agarose gel electrophoresis. The results indicated that the curcumin zinc complex exhibited less DNA binding constant among the four metal ion complexes than all the other compounds tested, confirming its weak interaction. Conclusion: Moreover, all the compounds degrade plasmid DNA, confirming their DNA cleavage activity. From our findings, these compounds will pave the way for developing new anticancer drugs with less toxicity.

Copper(II) and Zinc(II) complexes of new water-soluble Schiff base ligands and their antiproliferative properties towards mesothelioma cell line

In this work, three Schiff base ligands (HL1-HL3) containing a triphenyl phosphonium cation and their Cu(II) and Zn(II) complexes with the general formulae of [M(L)Cl2] were synthesized and their structures were characterized by spectroscopic and analytical methods. Crystal structure of complex [Zn(L1)Cl2] was determined. In the structure of the complex, each Zn(II) ion is four coordinated binding to phenolate oxygen and imine nitrogen atoms of the ligand L1 and two chloride atoms in approximately tetrahedral geometry. The equilibrium geometry of three Schiff base ligands (HL1-HL3) and their Cu(II) and Zn(II) complexes were calculated using the density functional theory (DFT/B3LYP) method with the 6–31++G(d,p) basis set for the C, H, Cl, N, O, P atoms and LANL2DZ for the I atom. Frontier molecular orbitals (HOMO, LUMO) analyses were conducted for the optimized geometries of the compounds, and chemical reactivity descriptors such as hardness, softness, electrophilicity, and electronegativity were examined. Additionally, the molecular electrostatic potential (MEP) of all compounds was modeled using DFT calculations. These calculations were thoroughly examined, and their implications were discussed. The ligands and their metal complexes were investigated for their DNA binding properties. The compounds showed comparable DNA binding properties to ethidium bromide (EB) and 5-fluorouracyl (5-Fu) with DNA binding constant (Kb) 1.5–6.25 × 105 M−1. The cytotoxic properties of the compounds towards HUVEC and H2452 (mesothelioma cell line) cells were investigated using an MTS assay. The IC50 values determined for HUVEC cells were found to range between 27.28 µg/mL ([Cu(L2)Cl2]) and 273.1 µg/mL ([Zn(L2)Cl2]), while in H2452 cells, they varied from 39.48 µg/mL ([Cu(L2)Cl2]) to 319.3 µg/mL ([Zn(L3)Cl2]). The compounds HL1, HL3, and [Zn(L3)Cl2] exhibited antioxidant activity at the highest concentration (750 µg/mL) only, while [Zn(L1)Cl2], HL2, [Zn(L2)Cl2], [Cu(L2)Cl2], and [Cu(L3)Cl2] showed antioxidant activity at 250 µg/mL.

One-Pot, Multi-Component Green Microwave-Assisted Synthesis of Bridgehead Bicyclo[4.4.0]boron Heterocycles and DNA Affinity Studies.

Anthranilic acids, salicylaldehydes and arylboronic acids reacted in EtOH/H2O (1/3) at 150 °C under microwave irradiation for 1 h to give, in excellent yields and purity, twenty-three bridgehead bicyclo[4.4.0]boron heterocycles via one-pot, three-component green synthesis. The scope and the limitations of the reactions are discussed in terms of the substitution of ten different anthranilic acids, three salicylaldehydes and three arylboronic acids. The replacement of salicylaldehyde with o-hydroxyacetophenone demanded a lipophilic solvent for the reaction to occur. Eight novel derivatives were isolated following crystallization in a toluene-containing mixture that included molecular sieves. The above one-pot, three-component reactions were completed under microwave irradiation at 180 °C within 1.5 h, thus avoiding the conventional prolonged heating reaction times and the use of a Dean-Stark apparatus. All derivatives were studied for their affinity to calf thymus DNA using proper techniques like viscosity and UV-vis spectroscopy, where DNA-binding constants were found in the range 2.83 × 104-8.41 × 106 M-1. Ethidium bromide replacement studies using fluorescence spectroscopy indicated Stern-Volmer constants between 1.49 × 104 and 5.36 × 104 M-1, whereas the corresponding quenching constants were calculated to be between 6.46 × 1011 and 2.33 × 1012 M-1 s-1. All the above initial experiments show that these compounds may have possible medical applications for DNA-related diseases.

Synthesis, spectral elucidation and DNA binding studies of cadmium(II) carboxylates with nitrogen donor heteroligands

A new series of novel homoleptic and heteroleptic Cd(II) complexes using cyclopropanecarboxylic acid (HL1) and cyclopentanecarboxylic acid (HL2) as main ligands and N-donor species like 2,2′-bipyridine (bpy), 1,10-phenanthroline (phen), and 2,9-dimethyl-1,10-phenanthroline (Me2phen) as co-ligands were prepared and characterized by FT-IR, multinuclear (1H and 13C) NMR, and UV–Visible spectroscopies. Furthermore, the crystal structure of the Cd(II) complex coordinated by cyclopentanecarboxylic acid (HL2) and 1,10-phenanthroline (phen) was explored by single crystal X-ray diffraction (SC-XRD) analysis. The crystal structure was binuclear, in which the coordination geometry around each cadmium center was distorted pentagonal bipyramidal coordination geometry. Various intermolecular interactions were accountable for stabilizing the supramolecular associations, which were seen by Hirshfeld surface analysis in terms of interatomic contacts. The spectroanalytical data of the synthesized complexes confirm the absence of the –OH band in the spectra of complexes as compared to the spectra of the free ligands, which favour the formation of complexes. The nature of complex-DNA interaction and the effect of the coordination of heteroligands on the binding strength of complexes were probed through UV–Visible spectroscopy and cyclic voltammetry. The obtained data confirm that the interaction of DNA with the complexes is dual: intercalation as well as groove binding. The DNA binding constants (Kb) and Gibb’s free energy changes (ΔG) were also determined for these complexes. This study aims to project effective drugs with the least harmful effects that could be useful for mankind against dreadful diseases.

Donepezil-Squaric Acid Hybrid: Synthesis, Characterization and Investigation of Anticholinesterase Inhibitory, DNA Binding and Antioxidant Properties

A novel donepezil-squaric acid (DS) hybrid compound was designed, synthesized and biologically evaluated as multi-target-directed ligands against neurodegenerative disease by fusing a fragment of donepezil (D) and squaric acid (S). This study focuses on investigating the binding mechanism of double-stranded fish sperm DNA (Fsds-DNA) with DS and S. The interaction between DS and S with Fsds-DNA was explored using spectrophotometric and viscometric methods. Besides, DNA binding constants (Kb) were determined. The results reveal that DS binds to Fsds-DNA via the minor groove binding mode. The hybrid molecule demonstrates potent inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Furthermore, it exhibits significant antioxidant activity, surpassing the scavenging ability of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals compared to squaric acid alone. In conclusion, these results suggest that the hybrid molecule may serve as a potential multifunctional agent for the treatment of Alzheimer’s disease.

Mononuclear η6-arene ruthenium(II) complexes with pyrazolyl-pyridazine ligands: synthesis, CT-DNA binding, reactivity towards glutathione, and cytotoxicity.

Organometallic η6-arene ruthenium(II) complexes with 3-chloro-6-(1H-pyrazol-1-yl)pyridazine (Ru1, Ru2, and Ru5) and 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)pyridazine (Ru3-4) N,N' heterocyclic and η6-arene (cymene (Ru1-4) or toluene (Ru 5)) have been synthesized. The ruthenium(II) complexes have common "three-legged piano-stool" pseudo-octahedral structures known for half-sandwich complexes. Evolution of their UV-Visible absorption spectra in PBS buffer or DMSO over 24h confirmed their good solvolysis stability. Titrations of the complexes with the calf thymus DNA (CT-DNA) were monitored using UV-Visible absorption and fluorescence spectroscopies. The complexes interact moderately with CT-DNA and their binding constants are in the order of 104M-1. Competitive binding of the complexes to a DNA-Hoechst 33,258 depicted competitive displacement of Hoechst from DNA's minor grooves. These complexes bind to glutathione forming GSH-adducts through S coordination by replacement of a halide, with the iodo-analogues having higher binding constants than the chloro-complexes. Cyclic voltammograms of the complexes exhibited one electron-transfer quasi-reversible process. Trends in the molecular docking data of Ru1-5/DNA were similar to those for DNA binding constants. Of the five, only Ru1, Ru3 and Ru5 showed some activity (moderate) against the MCF-7 breast cancer cells with IC50 values in the range of 59.2-39.9 for which Ru5 was the most active. However, the more difficult-to-treat cell line, MDA-MB 231 cell was recalcitrant to the treatment by these complexes.

Nonperipherally and peripherally substituted water‐soluble magnesium (II) phthalocyanines and their DNA binding, nuclease activities

In this study, magnesium (II) phthalocyanines (2a, 3a) and their water‐soluble derivatives (2b, 3b) were synthesized via multistep reactions. The structures of these phthalocyanines were identified by FT‐IR, NMR, MALDI‐TOF, and UV–Vis spectroscopy. The ct‐DNA binding (UV–Vis absorption, competitive EB binding, and agarose electrophoresis studies) and supercoiled plasmid DNA nuclease properties (hydrolytic, photonuclease, oxidative nuclease, and photooxidative nuclease) of the water‐soluble compounds were investigated using different methods. The DNA binding constant (Kb) values of 2b and 3b were calculated as 8.45 ± (0.25) × 104 and 7.71 ± (0.13) × 104 M−1 at 25°C, respectively. The results showed that 2b had a stronger ct‐DNA binding effect than 3b according to Kb and r values. The DNA nuclease studies claimed that both compounds indicated photonuclease activity on plasmid DNA depending on the light dose. Additionally, 2b had a higher photonuclease capacity than 3b. All of these results showed that 2b had promising potential as a photosensitizer agent for photodynamic therapy.

Cyrene™ as a green alternative to N,N'-dimethylformamide (DMF) in the synthesis of MLCT-emissive ruthenium(II) polypyridyl complexes for biological applications.

Ruthenium(II) polypyridyl complexes (RPCs) that emit from triplet metal-to-ligand charge transfer (MLCT) states find a wide variety of uses ranging from luminophores to potential anti-cancer or anti-bacterial therapeutics. Herein we describe a greener, microwave-assisted synthetic pathway for the preparation of homoleptic [Ru(N^N)3]2+ and bis-heteroleptic [Ru(N^N)2(N'^N')]2+ type complexes. This employs the bio-renewable solvent Cyrene™, dihydrolevoglucosenone, as a green alternative to N,N'-dimethylformamide (DMF) in the synthesis of Ru(N^N)2Cl2 intermediate complexes, obtaining comparable yields for N^N = 2,2'-bipyridine, 1,10-phenanthroline and methylated derivatives. Employing these intermediates, a range of RPCs were prepared and we verify that the ubiquitous luminophore [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) can be prepared by this two-step green pathway where it is virtually indistinguishable from a commercial reference. Furthermore, the novel complexes [Ru(bpy)2(10,11-dmdppz)]2+ (10,11-dmdppz = 10,11-dimethyl-dipyridophenazine) and [Ru(5,5'-dmbpy)2(10,11-dmdppz)]2+ (5,5'-dmbpy = 5,5'-dimethyl-bpy) intercalate duplex DNA with high affinity (DNA binding constants, Kb = 5.7 × 107 and 1.0 × 107 M-1, respectively) and function as plasma membrane and nuclear DNA dyes for confocal and STED microscopies courtesy of their long-lived MLCT luminescence.

Schiff bases containing 1,2,3-triazole group and phenanthroline: Synthesis, characterization, and investigation of DNA binding properties

In our study, the synthesis of Schiff base compounds C and D containing the phenanthroline structure and 1,2,3-triazole group was carried out in accordance with the literature. Structural characterization of the synthesized compounds was carried out using methods such as FT-IR, 1H, 13C NMR, UV–vis and Photoluminescence spectroscopy. Information regarding the interaction properties of the materials obtained within the scope of the study with the DNA structure was collected using UV–vis, viscosity tests and Photoluminescence spectroscopy methods. Data were collected about the DNA binding types, mode and energies of the Schiff base compounds synthesized within the scope of the study. As a result of the interaction of compounds C and D with the DNA structure, calibration equations, correlation coefficients (r2), DNA binding constants (Kb) and fluorescence spectrum extinction coefficient (Ksv) of EB-DNA were calculated. UV–vis, EB competitive binding and viscosity studies showed that compounds C and D interact with DNA via the groove binding mode. The Kb binding constants of substances C and D were calculated as 1.43×104 M−1 and 3.0×104 M−1, respectively, and the Ksv quenching constants were calculated as 5.34x104 M−1 and 0.6x104 M−1, respectively.

Biophysical studies of single and double alkyl chain metallosurfactants in presence of ionic liquids as additive on its binding to calf thymus DNA

In this work, a binding study of DNA in ionic liquid media of single and double alkyl chain metallosurfactants types (trans-[Co(DH)2(HA)Cl]2+ (1) and trans-[Co(DH)2(HA)2]3+ (2)) where DH = dimethyl glyoxime and HA = hexadecylamine, have been carried out by various spectral techniques. The experimental results indicating that size and shape of the ligand and hydrophobicity of these complexes marked effect on the binding affinity of the complexes to CT DNA in groove binding mode and the order of their intrinsic DNA binding constants kb is kb = 1.2 × 105 (1) < kb 3.6 × 105 (2). In the presence of an ionic liquid additive, the binding strength of the surfactant-cobalt(III) complex to the DNA increased due to the double alkyl chain of metallosurfactant, being more hydrophobic, exhibits strong binding towards DNA in comparison to the single alkyl chain. This indicates that the long aliphatic chain amine ligand/s present in the metallosurfactant-oxime complex (2) play a definite role in the binding between the metallosurfactant-oxime complex and DNA through their hydrophobicity. Ethidium bromide (EB) shows that these complexes exhibit the ability to displace the DNA-bound EB indicating that the complexes bind to DNA in groove binding site. Observed changes in the circular dichoric spectra of DNA in the presence of metallosurfactant complexes support the strong binding of complexes with DNA. Cyclic voltammetry results also confirm this mode of binding. The results reveal that the extent of DNA binding of (2) was greater than that of (1).

Synthesis, Antioxidant, Molecular Docking and DNA Interaction Studies of Metal-Based Imine Derivatives.

Currently, numerous ongoing studies are investigating the interaction of free radicals with biological systems, such as lipids, DNA and protein. In the present work, synthesis, characterization, antioxidant, DNA binding and molecular docking studies of Schiff base ligand and its Ni(II), Co(II), Cu(II) and Zn(II) were evaluated. The metal complexes have shown significant dose-dependent antioxidant activities higher than those of the free ligand but lesser than those of the standard antioxidant, ascorbic acid. The DNA binding constants (Kb) were found in the order Zn(pimp)2 {9.118 × 105 M-1} > H-pimp {3.487 × 105 M-1} > Co(pimp)2 {3.090 × 105 M-1} > Ni(pimp)2 {1.858 × 105 M-1} > Cu(pimp)2 {1.367 × 105 M-1}. Binding constants (Kb) values calculated from the molecular docking analysis were found to be in close agreement with the experimental results. The obtained results indicate the importance of synthesis complexes as a source of synthetic antioxidants and anticancer drugs.

Investigation of photoluminescence and DNA binding properties of benzimidazole compounds containing benzophenone group

The synthesis of benzimidazole compounds containing benzophenone group in accordance with the literature and the investigation of DNA binding properties of these compounds by using UV-vis and photoluminescence spectroscopy methods constitute the basis of this research. The structures of the compounds were determined by methods such as FT-IR, 1H, 13C NMR, UV-vis, Photoluminescence spectroscopy, and X-ray crystallography. By using methods such as UV-vis, Photoluminescence spectroscopy, and viscosity tests, information were collected about the binding types, binding mode, and binding energies of the compounds with DNA. In addition, the binding interactions of the compounds with DNA were investigated using the molecular docking technique. Using this information, calibration equations, correlation coefficients (r 2), and DNA binding constants (Kb ) were calculated for their compounds. The binding constants (Kb ) calculated for substances A, B, and C were found to be 3.0 × 104 , 7.0 × 104 , and 3.0 × 104 M−1, respectively. UV-vis, EB competitive binding, and viscosity tests showed that the compounds tended to bind to the DNA structure via the groove binding mode. At the end of molecular docking studies, it was determined that compound B showed the best DNA binding activity in in vitro studies. Compared with the studies in the literature, it is thought that the synthesized compounds can take place in cancer drug research as DNA binding agents. Communicated by Ramaswamy H. Sarma

Pharmacological Properties of &lt;i&gt;Genista sagittalis&lt;/i&gt; L. (Fabaceae) Grown in Turkey

The genus Genista L. (Family: Fabaceae) is a plant having several traditional uses for treating common ailments such as diabetes, ulcer, and respiratory diseases. In this current study, the composition of essential oil and the biological activities of Genista sagittalis L. (Fabaceae) from Kocaeli: Yuvacık Dam Basin have been studied. A total of fourteen components were identified in the essential oil. The identified compounds belonged to straight-chain alkane, aromatic ether, and terpenoid derivatives. The antibacterial activity analyses demonstrated that G. sagittalis flower extract only had low activity against P. mirabilis and P. aeruginosa with MICs 1 to 2 mg/mL, as the peduncle extract showed strong anti-QS activity at 1.3 mg/mL. To the best of our knowledge, the current work is the first to report the antimicrobial and anti-quorum sensing activity of G. sagittalis growing in Turkey. Double-stranded DNA binding affinity investigations of the flower and peduncle ethanol extracts indicate that there are interactions with double-stranded DNA and related binding constants (Kb) were found as 1.97×103±0.37 and 3.68×102±0.44 for the flower and peduncle extract, respectively.

Synthesis and study of some properties of new tetrazole-containing derivatives of morpholin-4-yl-1,3,5-triazine and 4-methylpiperidin-1-yl-1,3,5-triazine

New tetrazole-containing derivatives of morpholin-4-yl-1,3,5-triazine and 4-methylpiperidin-1-yl-1,3,5-triazine were synthesized. Cytotoxic activity of the compounds obtained against human liver tumor cell lines Huh-7 and human lung A549 was studied by the MTT test. It was shown that these substances do not exhibit a pronounced cytotoxic effect. The most significant antitumor activity was shown by 1,3,5-triazine containing 5-phenyltetrazol-2-ylacetohydrazide fragment and 4-methylpiperidine ring as substituents, as well as 1,3,5-triazine containing 5-methyl-1 H -tetrazol-1-ylacetohydrazide fragment and two morpholine rings. For these compounds, the interaction with DNA was studied by UV spectroscopy. For N ’-(4,6-dimorpholino-1,3,5-triazin-2-yl)-2-(5-methyl-1 H -tetrazol-1-yl)acetohydrazide, the DNA binding constant was determined ( K bin 9.02× 104 M.-1) and studied the ability to inhibit the tyrosine kinase domain of surface receptors. It was shown that the studied tetrazole-containing derivatives of 1,3,5-triazine do not exhibit antioxidant properties with respect to NO-radicals and do not cause photoinduced hemolysis.

Synthesis, characterization, and biological activity of sterically hindered fluorine-containing platinum(II) complexes

Picoplatin is a sterically hindered antitumor compound with unique chemical and DNA binding properties, but its curative effect is not as good as other platinum drugs. Therefore, a series of sterically hindered fluorine-containing platinum(II) complexes Y1–Y5 were synthesized and characterized by introducing fluorine atoms at the 2-position of the pyridine group and different leaving group ligands. In vitro antiproliferative activity assessments of these complexes have been performed against A549, MCF-7, SW480, HCT116, HepG2 human cancer cell lines, and LO2 normal cells. The results showed that Y1 with 2-fluoropyridine coordination and chloride ion as the leaving group exhibited stronger antiproliferative activity and selectivity in the tested cancer cell lines, especially for A549 cancer cells. DNA binding constants were determined by UV absorption and fluorescence titration, and the binding ability of Y1 to DNA is much stronger than that of the others, which shows Y1 has better DNA damage ability. For the determination of apoptosis by the complex, the results were consistent with those of the MTT assay, and the apoptosis rate of Y1 reached 38.9%. Therefore, our work offers an advantageous method for the development of new platinum-based antitumor drugs.

Erbium(III) coordination compounds with substituted salicylaldehydes: Characterization and biological profile

Five erbium(III) complexes with salicylaldehyde (saloH for 1), and mono– (5–X–saloH; X = NO2 and Me for 2 and 3, respectively) or di–substituted salicylaldehydes (3,5–diX–saloH; X = Cl and Br for 4 and 5, respectively) were synthesized and characterized by physicochemical and spectroscopic techniques and single–crystal X–ray crystallography. All five complexes have the general formula [Er(deprotonated salicylaldehyde)3(MeOH)(H2O)]. The structure of complexes [Er(3,5–diCl–salo)3(MeOH)(H2O)]·1.5MeOH (complex 4) and [Er(3,5–diBr–salo)3(MeOH)(H2O)]·1.75MeOH (complex 5) were verified by single–crystal X–ray crystallography. The evaluation of antioxidant activity of the complexes was focused on their ability to scavenge 1,1–diphenyl–picrylhydrazyl and 2,2′–azinobis–(3–ethylbenzothiazoline–6–sulfonic acid) free radicals and to reduce H2O2. The interaction of the complexes with calf–thymus DNA was investigated by UV–vis spectroscopy, viscosity measurements and via competitive studies with ethidium bromide in order to evaluate the possible DNA–binding mode and to determine the corresponding DNA–binding constants. The affinity of the complexes for bovine and human serum albumins was explored by fluorescence emission spectroscopy and the corresponding binding constants were determined.

A fluorene based imine compound: Structural characterization, DNA binding properties and fluorescence sensor properties towards metal ions

In the course of this work, a new fluorene-based Schiff base compound (SB) from the condensation reaction 2-aminofluorene and 4-(diethylamino)salicylaldehyde was synthesized and its structure was characterized by FTIR, 1H/13C NMR spectroscopies and elemental analysis. Crystal structure of the synthesized compound (SB) was determined single crystal X-ray diffraction study. Crystal structure of the compound was solved in monoclinic unit cell and P21 space group. The molecule shows phenol-imine intramolecular hydrogen bond and molecules are connected by CH····π interactions. The Schiff base compound was then screened for its DNA binding properties by using UV–vis absorption, fluorescence and viscosity studies. All DNA binding data showed that the compound interacts with FSdsDNA via intercalation. The intrinsic DNA binding constant of the compound from UV–vis spectral data was 3.00×104 M−1 which is significantly lower than ethidium bromide (an intercalating agent). The compound was further investigated for colorimetric sensing of metal ions. Colorimetric sensor properties of the compound towards Fe(III), Pb(II), Zn(II), Cu(II), Al(III), Hg(II), Co(II), Mn(II) and Ni(II) ions were investigated in solution. The compound showed selective sensing properties for Cu(II) under 365 nm light. Jobs variation study indicated that the Cu(II) to receptor ratio was 2:1.

Water-soluble meso-thienyl BODIPY therapeutics: Synthesis, characterization, exploring photophysicochemical and DNA/BSA binding properties

Recently, there is rising attention in photodynamic therapy (PDT) compared to traditional methods (immunotherapy, surgery, chemotherapy or radiotherapy) in the treatment of cancer. This method includes the sensitizers which are activated to generate cytotoxic reactive oxygen species (ROS). BODIPYs are known as one of the sensitizers used in PDT applications. Encouraged by these fact in this study, we present the synthesis of novel BODIPY derivatives with meso-thienyl segment, diiodine moieties at 2-,6-positions and distyryl structure at 3-,5-positions. The characterization of all compounds was performed by using various spectroscopic methods (UV–Vis, FT-IR, Mass, 1H-NMR and 13C-NMR spectroscopy). To assess the potentials of the synthesized compounds in PDT applications, fluorescence, singlet oxygen and photodegradation quantum yields were calculated. Singlet oxygen quantum yields are 0.03, 0.84, 0.13, 0.32 and 0.76 for BODIPY compounds 1–5, respectively. Besides the photophysicochemical studies, DNA/BSA binding experiments for water-soluble BODIPY derivative (5) were examined. For water-soluble BODIPY derivative 5, the DNA binding constant (Kb) is 1.75 × 105 and the BSA binding constant (KBSA) is 4.15 × 104.

Preliminary investigation on biological possessions of Saquinavir‐modified quinoline‐derived azadipeptidomimetics

AbstractHerein, azadipeptidomimetic molecules were designed and synthesized using a quinoline‐histidine‐amino acid sequence with terminal amino acid modification. In‐silico studies were carried out to evaluate the compound's HIV protease‐1 inhibition temperament. In‐vitro anti‐proliferative possessions of the test compounds were studied by executing a series of experiments, namely DNA binding, bovine serum albumin (BSA) binding capability, and cytotoxicity assay on MCF‐7 cells. The molecule 5j exhibited remarkable results in all experiments; it has an excellent DNA binding constant (3.76 × 105), higher serum albumin unbound concentration of 5.96%, and a significant antiproliferative effect on MCF‐7 cells with IC50 value 0.31 nM.

An Integrated Analysis of Mechanistic Insights into Biomolecular Interactions and Molecular Dynamics of Bio-Inspired Cu(II) and Zn(II) Complexes towards DNA/BSA/SARS-CoV-2 3CLpro by Molecular Docking-Based Virtual Screening and FRET Detection.

Novel constructed bioactive mixed-ligand complexes (1b) [CuII(L)2(phen)] and (2b) [ZnII(L)2(phen)] {where, L = 2-(4-morpholinobenzylideneamino)phenol), phen = 1,10-phenanthroline} have been structurally analysed by various analytical and spectroscopic techniques, including, magnetic moments, thermogravimetric analysis, and X-ray crystallography. Various analytical and spectral measurements assigned showed that all complexes appear to have an octahedral geometry. Agar gel electrophoresis's output demonstrated that the Cu(II) complex (1b) had efficient deoxyribonucleic cleavage and complex (2b) demonstrated the partial cleavage accomplished with an oxidation agent, which generates spreadable OH● through the Fenton type mechanism. The DNA binding constants observed from viscosity, UV-Vis spectral, fluorometric, and electrochemical titrations were in the following sequence: (1b) &gt; (2b) &gt; (HL), which suggests that the complexes (1b-2b) might intercalate DNA, a possibility that is supported by the biothermodynamic measurements. In addition, the observed binding constant results of BSA by electronic absorption and fluorometric titrations indicate that complex (1b) revealed the best binding efficacy as compared to complex (2b) and free ligand. Interestingly, all compounds are found to interact with BSA through a static approach, as further attested by FRET detection. The DFT and molecular docking calculations were also performed to realize the electronic structure, reactivity, and binding capability of all test samples with CT-DNA, BSA, and the SARS-CoV-2 3CLPro, which revealed the binding energies were in a range of -8.1 to -8.9, -7.5 to -10.5 and -6.7--8.8 kcal/mol, respectively. The higher reactivity of the complexes than the free ligand is supported by the FMO theory. Among all the observed data for antioxidant properties against DPPH᛫, ᛫OH, O2-• and NO᛫ free radicals, complex (1a) had the best biological efficacy. The antimicrobial and cytotoxic characteristics of all test compounds have been studied by screening against certain selected microorganisms as well as against A549, HepG2, MCF-7, and NHDF cell lines, respectively. The observed findings revealed that the activity enhances coordination as compared to free ligand via Overtone's and Tweedy's chelation mechanisms. This is especially encouraging given that in every case, the experimental findings and theoretical detections were in perfect accord.