Ataf Ali Altaf

New supramolecular ferrocenyl amides: synthesis, characterization, and preliminary DNA-binding studies

Three ferrocenyl amides have been synthesized and characterized by analytical techniques. Based on single-crystal X-ray analysis, a supramolecular structure was attributed to 1 owing to the presence of intermolecular non-covalent interactions. UV-Visible spectroscopy, viscometry, and dynamic laser light scattering was used to assess the mode of interaction and binding of these complexes with DNA, which varied in the sequence 1 > 2 > 3. The binding is presumably due to the ability of these complexes to form secondary non-covalent interactions with DNA bases. Complex-DNA adduct formation depends on the nature of R of the amide.

New supramolecular ferrocene incorporated N,N′-disubstituted thioureas: synthesis, characterization, DNA binding, and antioxidant studies

Ferrocene incorporated N,N′-disubstituted thioureas (S1–S6) were synthesized by allowing 4-ferrocenyl-3-methylaniline to react with freshly prepared aliphatic isothiocyanates and were characterized by using different analytical techniques. Based on single-crystal X-ray analysis compound S1 shows supramolecular structure mediated by secondary bonding interactions, intermolecular hydrogen bonding NH–O, NH–S, and secondary non-covalent interactions (π–H). Voltammetric measurements were used to study their redox behavior and DNA binding of the compounds. Different binding parameters like binding constants, binding energies, and diffusion coefficients (Do) were calculated for further insight on the affinity with DNA. All the compounds show electrostatic mode of interactions. The Do of molecule-DNA adducts were found to be lower than that of free molecule. Compounds S1–S6 having 50% inhibition values less than 37.89 μg mL−1 indicate that they may have value as antioxidants to be used as therapeutic agents. Graphical Abstract This research article describes the synthesis, structural characterization, electrochemistry, nature and extent of binding with the DNA and free radical scavenging activity of new ferrocene based N, N′-disubstituted thioureas.

Naked Eye DNA detection: Synthesis, characterization and DNA binding studies of a novel azo-guanidine

A novel class of azo-guanidine compounds is introduced in this article. The novel compound 2-(2-hydroxyphenyl)-1-(phenylamino)-3-(phenylimino)guanidine (AG) was synthesized and well characterized by using different analytical instrumental techniques like elemental analysis, FTIR, (1)H and (13)C NMR, UV-Visible spectroscopy and cyclic voltammetry. The new compound was found interacting with DNA and shows clear color change in the solution. The AG-DNA complex was qualitatively and quantitatively characterized with UV-Visible spectroscopy and cyclic voltammetry. Electrostatic mode of interaction, clear color change and moderate binding constant (K(b)=10(4)) indicate its potential use as DNA staining agent.

Synthesis of N-(6-Arylbenzo[d]thiazole-2-acetamide Derivatives and Their Biological Activities: An Experimental and Computational Approach

A new series of N-(6-arylbenzo[d]thiazol-2-yl)acetamides were synthesized by C-C coupling methodology in the presence of Pd(0) using various aryl boronic pinacol ester/acids. The newly synthesized compounds were evaluated for various biological activities like antioxidant, haemolytic, antibacterial and urease inhibition. In bioassays these compounds were found to have moderate to good activities. Among the tested biological activities screened these compounds displayed the most significant activity for urease inhibition. In urease inhibition, all compounds were found more active than the standard used. The compound N-(6-(p-tolyl)benzo[d]thiazol-2-yl)acetamide was found to be the most active. To understand this urease inhibition, molecular docking studies were performed. The in silico studies showed that these acetamide derivatives bind to the non-metallic active site of the urease enzyme. Structure-activity studies revealed that H-bonding of compounds with the enzyme is important for its inhibition.

Study of New Ferrocene Incorporated N,N′-Disubstituted Thioureas as Potential Antitumour Agents

In this paper, we report the synthesis, structural characterisation, cytotoxicity against human ovarian tumour models (A2780, A2780cisR, and A2780ZD0473R), nature of interaction with calf-thymus (CT)-DNA and pBR322 plasmid DNA of new ferrocene based N,N′-disubstituted thioureas (3a–d). The compounds, characterized based on elemental analysis, FT-IR and multinuclear (1H and 13C) NMR spectroscopy, and single crystal X-ray diffractometry, were found to have significant antitumour activity although much less than cisplatin. Crystallographic data reveals the existance of secondary interactions for compound 3c in terms of intermolecular hydrogen bonding of type NH⋯O, NH⋯S and secondary non-covalent interactions (π⋯H). When pBR322 plasmid DNA was interacted with increasing concentrations of compounds, 3a and 3b but not 3c were found to partially prevent BamH1 digestion of the DNA. The negative shift in peak potential in voltammetric measurements indicates that all the compounds undergo electrostatic interactions with the negatively charged phosphate DNA backbone. The large negative value of the binding energy indicates the spontaneity of reaction between the compounds and CT-DNA and the conformational stability of adducts formed.

Zirconium complexes in homogeneous ethylene polymerization

This article reviews the recent progress of zirconium complexes for ethylene polymerization. Zirconium complexes are one of the most important types of catalysts for homogeneous ethylene polymerization. Polymerization behavior and polymer structure can be adjusted through the balancing of ligand structure. We surveyed the zirconium complexes synthesized from 2006 to early 2009 and summarize their comparative catalytic activities. Generally, the main factor observed is the steric bulk which on increasing reduces the catalytic activity. Electron count, electronic cloud, and inductive effect also influence the catalytic activity.

Solvothermal Preparation of ZnO Nanorods as Anode Material for Improved Cycle Life Zn/AgO Batteries

Nano materials with high surface area increase the kinetics and extent of the redox reactions, thus resulting in high power and energy densities. In this study high surface area zinc oxide nanorods have been synthesized by surfactant free ethylene glycol assisted solvothermal method. The nanorods thus prepared have diameters in the submicron range (300∼500 nm) with high aspect ratio. They have uniform geometry and well aligned direction. These nanorods are characterized by XRD, SEM, Specific Surface Area Analysis, solubility in alkaline medium, EDX analysis and galvanostatic charge/discharge studies in Zn/AgO batteries. The prepared zinc oxide nanorods have low solubility in alkaline medium with higher structural stability, which imparts the improved cycle life stability to Zn/AgO cells.

N-(4-Ferrocenylphenyl)benzamide

In the title compound, [Fe(C5H5)(C18H14NO)], the unsubstituted cyclopentadienyl ring is disordered over two sets of sites with occupancy ratio of 0.55 (1):0.45 (1). One conformation has the rings eclipsed and the other staggered. An intramolecular C—H⋯O hydrogen bond forms an S(6) ring motif. In the crystal, intermolecular C—H⋯O and N—H⋯O hydrogen bonds lead to R 2 1(7) ring motifs. The molecules are linked into polymeric chains extending along the b axis.

Biologically Active New N, N', N''-Tri-Substituted Ferrocenyl Phenylguanidines and their Characterization.

BACKGROUND Introducing new candidates for various biological targets is a prime characteristic of the present day medicinal research and development. Guanidines are the important bioactive compounds and are well recognized for their diverse biological activities, especially as anticancer, antimicrobial and antioxidant agents. Due to the favorable electronic properties of ferrocene like lipophilicity, redox activity, stability in solution state and its easy derivatization, have made ferrocenyl compounds very popular molecules for biological uses. OBJECTIVES Keeping in sight, it is valuable to synthesize ferrocenyl guanidines to increase the binding potency with DNA, make them redox active and more lipophilic compounds. METHODS Six new ferrocenyl phenylguanidines (F1 - F6) have been synthesized via multi step protocol. The structures of F1 - F6 were established by using elemental analysis, UV-visible, multinuclear (1H and 13C) NMR and FTIR spectroscopy. Solution phase redox behavior, of the synthesized compounds, has been characterized by cyclic voltammetry. Two compounds (F2 & F4) were characterized by single crystal XRD. RESULTS Due to the biological importance of guanidines; these ferrocenyl guanidiens were screened for different biological activities like antibacterial, antifungal, antioxidant and DNA binding. DNA interaction study was done by using UV-visible spectrometry and cyclic voltammetry revealed good binding capacity of the test compounds. CONCLUSION The results revealed that the ferrocene incorporation to guanidines enhances their DNA binding ability. A similar trend was found in antioxidant and antimicrobial studies. Being the bioactive molecules these compounds are potential drug candidates.

Acid base co-crystal converted into porous carbon material for energy storage devices

A simple and facile method is adopted for the synthesis of pure and catalyst free carbon material for supercapacitor applications. In a co-crystal synthesis, the precursors (isophthalic acid and a base, 4,4′-bipyridine) are arranged in regular pattern, followed by carbonization at 600 °C under an inert atmosphere to produce pure carbon material, CIN-600. The obtained sample is characterized by many techniques, such as powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and gas adsorption analysis. The gas adsorption and microscopic analysis demonstrated the high porosity of the carbon sample and its irregular geometry. Owing to the excellent porosity and electrical conducting properties, CIN-600 showed enhanced capacitive performance when used as an electrode material in electric double layer capacitors. The specific capacitance of the sample was ca.181.3 F g−1 at 2 mV s−1 and maintained 91.3% of its initial capacitance in a long-term cycling test.