Muhammad Asif Iqbal

One-pot synthesis, characterization, DNA binding and enzymatic studies of 4-methyl trans-cinnamate zinc(II)-mixed ligand complexes

Four new zinc(II) complexes formulated as [Zn(L)2] (1), [Zn(L)2(phen)] (2), [Zn(L)2(bipy)H2O] (3), and [Zn(en)2(H2O)2](L)2(H2O)2 (4), where HL = 4-methyl trans-cinnamic acid, bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline, and en = ethylenediamine, have been synthesized and characterized by FT-IR and NMR spectroscopy. Single-crystal XRD revealed distorted square-pyramidal structure for 3 and octahedral for 4. The complexes were screened for DNA interaction via viscommetry and UV–visible spectroscopy. The apparent binding constants were calculated to be 1.18 × 104, 1.26 × 105, 4.64 × 104, and 1.89 × 104 for 1–4, respectively. The binding propensity to salmon sperm DNA was in the order: K2 > K3 > K4 > K1. Furthermore, these complexes demonstrated efficient inhibition of alkaline phosphatase, which was attributed to the binding of zinc(II) to the enzyme’s active site. Graphical abstract pictogram

Octahedral copper(II) carboxylate complex: synthesis, structural description, DNA-binding and anti-bacterial studies

Abstract Self-assembly of CuSO4, para-methyl-2-phenyl acetate and 1,10-phenanthroline afforded good-quality crystalline complex in quantitative yield. The complex was characterized by FTIR and UV-visible spectroscopy, electrochemistry, and powder and single-crystal XRD studies. Its structure was found to possess axially elongated octahedral symmetry with CuO4N2 chromophore. Its purity was assessed by powder XRD spectrum. Absorption study yielded a broad band corresponding to 2Eg→2T2 g transition. Electrochemical solution study indicated diffusion-controlled irreversible electron transfer process corresponding to Cu(II)/Cu(I) redox couple with diffusion coefficient = 7.89(±0.1)×10−9 cm2s−1. Results of spectroscopic techniques support each other. Complex exhibited excellent DNA-binding ability through UV-visible spectroscopy and cyclic voltammetry yielding Kb values 1.399 × 104 M−1 and 5.81 × 103 M−1, respectively. The complex exhibited significant activity against bacterial strains Escherichia coli, Micrococcus luteus and Staphylococcus aureus and good activity against Bacillus subtilis. These preliminary studies impart good biological relevance on the synthesized complex.

CHRONIC VIRAL HEPATITIS B

Objectives: To determine the frequency of liver fibrosis by non invasive markerin patients with chronic viral hepatitis B. Study Design: Cross sectional clearly investigate aboutchronic viral hepatitis population. Setting: Liaquat University Hospital Hyderabad. Period: Sixmonths, 09-Jan-2014 to 08-July-2014. Patients and Methods: All the patients of 16-50 years ofage, of either gender with chronic viral hepatitis B infection for more than 6 months duration wereadmitted and evaluated for liver fibrosis through non invasive marker (APRI). The SPSS was usedto manipulate the data. Results: During six month study period, total 140 patients with chronicviral hepatitis B infected patients were evaluated for liver fibrosis. Majority of patients were fromurban areas 112/140 (80%). The mean ±SD for age of patients with chronic viral hepatitis Binfection was 37.95±9.77. The mean age ±SD of hepatic fibrotic patients was 35.72±7.62.The mean ±SD for age of male and female population was 35.83±8.74 and 33.83 ± 6.53respectively. The mean ± SD for APRI score in hepatic fibrotic subjects was 1.31±0.31 while inrelation to liver fibrotic male and female patients it was 0.91±0.21 and 1.00±0.32 respectively.Majority of the subjects were 30-39 years of age and the male population predominant (p=0.02)whereas the liver fibrosis was identified in 89/140 (63.5) [p=<0.01] as far as gender distributionis concerned. Conclusion: APRI may be used as a simple and readily available tool for thediagnosis of significant fibrosis in patients with chronic viral hepatitis B.

Supramolecular Heteroleptic Copper(II) Carboxylates: Synthesis, Spectral Characterization, Crystal Structures, and Enzyme Inhibition Assay

Two new complexes of substituted phenyl acetic acids with CuSO4 · 5H2O and 2,2′-bipyridine (Bipy) with formula [CuL(Bipy)2]L · nH2O, where L = 2-ClC6H4CH2COO– (I), 2-CH3-3-NO2C6H3CH2COO– (II) and n = 3 (I); 4 (II), have been synthesized. These complexes have been characterized by elemental analysis, FT-IR and X-ray crystal diffraction (CIF file CCDC nos. 1487707 (I), 1487708 (II)). Both complexes are mononuclear and crystallize in the triclinic space group P1̅. In both complexes two molecules of Bipy bind equatorially with metal atom and one molecule of substituted phenyl acetic acid binds at axial position giving rise to a distorted five coordinated geometry around copper atom, while the second oxygen atom of carboxylate ligand appears to occupy the sixth position resulting in highly distorted six coordination environments around metal center in both complexes. However, another molecule of substituted phenyl acetic acid along with water molecules lies as co-crystal within the crystal lattice. Two bipyridine molecules in both complexes are lying in different planes and are oriented at dihedral angle of 63.89(8)° and 74.99(11)° in complexes I and II, respectively. Extensive hydrogen bonding because of water molecules present in crystal lattice plays a vital role in the formation of the 3D structure. Additionally, other weak interactions such as π–π interactions markedly influence the supramolecular structure. An investigation of DNA binding ability of both complexes using UV-visible spectroscopy and anti-diabetic capacity is also presented. Results revealed that synthesized complexes bind with SSDNA through intercalation as well as groove binding mode with Kb values of 2.45 × 104 and 7.72 × 103 M–1 for complex I and II, respectively. Complex II strongly inhibits in-vitro α-glucosidase with IC50 value of 30.4 μM, while complex I moderately inhibits in-vitro α-amylase with IC50 value of 69.9 μM. Acarbose was employed as standard in both assays.