Saeed-Ur Rehman

A thermal analysis study of 1,2-dipiperidinoethane complexes of cobalt, nickel, copper, zinc and cadmium by TG-DTG-DTA techniques

A number of complexes of the general formula ML(NO3)2, (M=Co(II), Ni(II), Cu(II), Zn(II) and Cd(II); L=1,2-dipiperidinoethane (DPE)) were prepared and studied by means of TG–DTG–DTA techniques. Their compositions were investigated by elemental analysis in order to ensure their purity and structural elucidations were based on conductivity measurements. room temperature magnetic measurement, proton NMR, and IR spectra. Thermal decomposition of these distorted tetrahedral complexes and their ligand took place in two distinct steps upon heating up to 720°C with the loss of inorganic and organic fragments and show almost the same mode of decomposition. The thermal degradation of all the complexes in static air atmosphere starts at temperature lower than observed for free ligand degradation. The composition of intermediates formed during degradation was confirmed by microanalysis and IR spectroscopy. The residues after heating above 600°C correspond to metal oxide. It follows from the results that thermal stability of the complexes increases in the following sequence: Ni(II)

Synthesis, characterization, in vitro antimicrobial, and U2OS tumoricidal activities of different coumarin derivatives.

BackgroundCoumarin and its derivatives are biologically very active. It was found that the enhanced activities are dependent on the coumarin nucleus. Biological significance of these compounds include anti-bacterial, anti-thrombotic and vasodilatory, anti-mutagenic, lipoxygenase and cyclooxygenase inhibition, scavenging of reactive oxygen species, and anti-tumourigenic. Our interest in medicinal chemistry of dicoumarol compounds have been developed by keeping in view the importance of coumarins along with its derivatives in medicinal chemistry. All the synthesized compounds were fully characterized by spectroscopic and analytical techniques and were screened for antimicrobial and U2OS bone cancer activities.Results4-hydroxycoumarin was derivatized by condensing with different aldehydes yielding the dicoumarol and translactonized products. Elemental analyses, ESI(+,−) MS, 1H and 13C{1H}-NMR, infrared spectroscopy and conductance studies were used to characterize the synthesized compounds which revealed the dicoumarol and dichromone structures for the compounds. The compounds were screened against U2OS cancerous cells and pathogenic micro organisms. The compounds with intermolecular H-bonding were found more active revealing a possible relationship among hydrogen bonding, cytotoxicity and antimicrobial activities.ConclusionCoumarin based drugs can be designed for the possible treatment of U2OS leukemia.

Neutron activation analysis and atomic absorption spectrophotometry for the analysis of fresh, pasteurized and powder milk

Specific gravity 1.074 1.060 1.026 1.021 1.023 1.025 1.025 1.021 1.016 1.027 1.024 − − Ca (mg/mL) 1.79±0.13 1.65±0.13 1.89±0.15 0.91±0.07 1.07±0.10 0.81±0.07 1.33±0.10 1.21±0.09 0.95±0.07 1.03±0.08 0.71±0.06 1.25±0.10 1.26±0.10 K (mg/mL) 1.04±0.09 1.31±0.11 1.18±0.10 1.29±0.12 1.32±0.12 1.15±0.10 1.31±0.12 1.20±0.11 0.81±0.07 1.23±0.11 0.78±0.07 1.09±0.10 1.13±0.10 Na (mg/mL) 0.56±0.05 0.44±0.04 0.45±0.04 1.27±0.11 0.97±0.08 1.13±0.09 0.73±0.06 0.95±0.08 0.71±0.06 1.45±0.13 0.52±0.04 0.60±0.05 0.73±0.06 Cl (mg/mL) 0.67±0.09 0.68±0.07 0.88±0.10 0.89±0.10 0.88±0.10 0.93±0.10 0.74±0.08 0.96±0.10 0.66±0.07 0.94±0.10 0.48±0.05 0.58±0.07 0.82±0.09 P (mg/mL) 0.55±0.06 0.28±0.02 0.33±0.03 0.15±0.01 0.33±0.04 0.27±0.02 0.15±0.01 0.15±0.02 0.15±0.01 0.18±0.01 0.21±0.03 0.25±0.03 0.21±0.02 Mg (mg/mL) 0.18±0.04 0.12±0.02 0.13±0.03 0.07±0.02 0.15±0.03 0.07±0.02 0.11±0.02 0.14±0.02 0.13±0.02 0.15±0.02 0.07±0.01 0.12±0.03 0.09±0.02 Zn (μg/mL) 6.39±0.48 6.73±0.48 5.00±0.37 2.84±0.22 3.55±0.27 2.34±0.18 4.29±0.32 3.75±0.28 2.93±0.22 3.19±0.24 3.04±0.23 6.39±0.48 4.22±0.32 Fe (μg/mL) 1.00±0.11 0.94±0.11 0.90±0.11 2.84±0.31 2.05±0.22 1.23±0.13 2.09±0.24 0.89±0.11 0.98±0.11 1.07±0.11 5.15±0.46 15.12±1.28 1.29±0.15 Sr (μg/mL) 2.97±0.23 1.48±0.13 4.20±0.32 2.29±0.21 2.78±0.22 1.76±0.14 2.38±0.20 2.93±0.22 2.35±0.17 2.54±0.18 1.44±0.11 2.96±0.23 2.51±0.20 I (μg/mL) 0.29±0.03 − − − 0.13±0.02 0.08±0.03 − − 10.41±1.00 − − 0.18±0.03 − Br (μg/mL) 2.01±0.16 1.67±0.13 4.58±0.32 1.93±0.15 1.93±0.15 1.55±0.11 1.94±0.15 2.00±0.15 2.15±0.16 2.05±0.15 1.44±0.11 1.13±0.09 2.69±0.20 Rb (μg/mL) 1.37±0.10 1.29±0.09 0.64±0.05 0.8±0.07 0.89±0.07 0.8±0.06 0.98±0.07 0.78±0.05 0.58±0.04 0.96±0.07 0.55±0.04 0.53±0.04 0.98±0.09 Ni (μg/mL) 0.15±0.01 0.21±0.01 0.17±0.01 0.10±0.01 0.10±0.01 − − 0.44±0.01 0.17±0.01 0.25±0.01 0.12±0.01 0.20±0.01 0.08±0.01 Cu (μg/mL) 0.15±0.01 0.12±0.01 0.13±0.01 0.09±0.01 0.19±0.01 0.14±0.03 0.20±0.04 0.08±0.01 0.07±0.01 0.17±0.01 0.05±0.01 0.27±0.01 0.21±0.01 Pb (ng/mL) − − − − 140±11 105±17 − − − − − − − Mn (ng/mL) − − − 105±10 − 149±9 − 113±8 181±7 120±6 76±7 109±12 −

Synthesis, Pyrolytic, and Antibacterial Study of 3-[(E)-(2-phenylhydrazinylidene)methyl]pyridine(PHMP) and Its Transition Metal Complexes

Phenyl hydrazine and pyridine-3-carbaldehyde were coupled to form a new Schiff base 3-[(E)-(2-phenylhydrazinylidene)methyl]pyridine(PHMP), followed by the formation of its transition metal derivatives (i.e., Co(II), Cu(II), and Zn(II) complexes). All of them were characterized by physical and spectral methods such as 1H-NMR, IR, elemental analysis, UV-Vis spectra, and conductance studies. Thermal study was carried out with TG/DTA method to understand the degradation pattern of the newly synthesized ligand and its complexes. Antibacterial study was carried out with both the gram-positive (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermis, Streptococcus pneumonia) and gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli). The complexes showed medium activity as compared to the standard imipenem.