Azim Khan

Preliminary investigation of anticancer activity by determining the DNA binding and antioxidant potency of new ferrocene incorporated N,N',N″-trisubstituted phenylguanidines.

Six new bioactive ferrocene based phenylguanidines were successively synthesized and characterized by means of various analytical techniques like elemental analysis, FT-IR, multinuclear ((1)H and (13)C) NMR, UV-Vis spectroscopy and cyclic voltammetry. The interaction of compounds with DNA was investigated by spectroscopic and cyclic voltammetric measurements. The interaction was found to be the electrostatic and the binding constants values were impressively larger. Compounds f-1, f-2, f-3 have slight larger binding constant values ranging from 0.8×10(5) to 2.4×10(5) as compared to g-1, g-2 and g-3 ranging from 7.6×10(4) to 1.1×10(5) which is most probably due to the presence of ferrocene at para position where the delocalization of electrons is maximum. Antioxidant activity was determined by UV-Vis spectrophotometer by using DPPH as a free radical. All the compounds exhibit good antioxidant activity and the results so obtained support the structure activity relationship.

New supramolecular ferrocenyl phenylguanidines as potent antimicrobial and DNA-binding agents

Six new ferrocenyl phenylguanidines have been synthesized and characterized by elemental analysis, FT-IR, multinuclear (1H and 13C) NMR, and single crystal analysis. The latter showed a supramolecular structure for 2 mediated by O H and π H interactions. A subsequent DNA-binding study of these complexes proved them to be good DNA binders with the binding constant varying in the range of 1.2–5.6 × 105 M−1. These compounds were found to have moderate antibacterial and significant antifungal activities, especially for compounds having a chlorophenyl. These compounds may emerge as a new class of anticancer and antifungal agents alone or in combination with other drugs.

Combined Application of Boron and Zinc Influence the Leaf Mineral Status, Growth, Productivity and Fruit Quality of ‘Kinnow’ Mandarin (Citrus nobilis Lour × Citrus deliciosa Tenora)

The deficiency of mineral nutrients, particularly of boron (B) and zinc (Zn) in many citrus orchards of Pakistan affect yield and quality. Effect of foliar application of B and Zn on leaf mineral nutrients, growth, productivity, and quality of ‘Kinnow’ were studied. Trees were sprayed with 37 mM boric acid and 49 mM zinc sulfate either alone or in combination at fruit setting stage or fruit setting and pre-mature stages. Leaf phosphorus (P), potassium (K), B, and Zn were significantly increased with treatments. Lowest fruit drop and maximum fruit weight and number, highest level of ascorbic acid, and reducing sugars were recorded in the trees sprayed with combine application of B and Zn at fruit set stage. In conclusion, combined application of B and Zn at fruit setting stage can be used effectively to increase nutrient uptake, reduce fruit drop, and increase yield with better quality of ‘Kinnow’ mandarin fruit.

2-(3-Chloro-benzo-yl)-3-(3,4-di-chloro-phen-yl)-1-(4-ferrocenylphen-yl)guanidine.

In the title compound, [Fe(C5H5)(C25H17Cl3N3O)], the isolated cyclopentadienyl (Cp) ring is disordered over two set of sites in a 0.577 (8):0.423 (8) ratio. The dihedral angle between the other Cp ring and its attached benzene ring is 13.6 (3)°, and that between the benzene ring and the guanidine group is 64.8 (2)°. One of the N—H groups forms both an intra- and an intermolecular N—H⋯O hydrogen bond; the other N—H group does not form any hydrogen bonds. In the crystal, pairs of the intermolecular N—H⋯O hydrogen bonds link the molecules into inversion dimers.

N-[(Methyl-sulfan-yl)meth-yl]benzamide.

In the title compound, C9H11NOS, the phenyl ring and formamide unit make a dihedral angle of 23.93 (14)°, whereas the (methylsulfanyl)methyl group is oriented at a dihedral angle of 61.31 (8)° with respect to the phenyl ring. There are intermolecular N—H⋯O hydrogen bonds, forming C(4) chains along the [010] direction. These polymeric chains are linked by C—H⋯O hydrogen bonds to form polymeric sheets in the (110) plane.

5-(4-Chloro­phen­yl)-2-fluoro­pyridine

In the title compound, C11H7ClFN, the chlorobenzene and 2-fluoropyridine rings are oriented at a dihedral angle of 38.83 (5)°. In the crystal, there are no hydrogen-bonding interactions.

Impact of city effluents on water quality of Indus River: assessment of temporal and spatial variations in the southern region of Khyber Pakhtunkhwa, Pakistan

The impact of city effluents on water quality of Indus River was assessed in the southern region of Khyber Pakhtunkhwa, Pakistan. Water samples were collected in dry (DS) and wet (WS) seasons from seven sampling zones along Indus River and the physical, bacteriological, and chemical parameters determining water quality were quantified. There were marked temporal and spatial variations in the water quality of Indus River. The magnitude of pollution was high in WS compared with DS. The quality of water varied across the sampling zones, and it greatly depended upon the nature of effluents entering the river. Water samples exceeded the WHO permissible limits for pH, EC, TDS, TS, TSS, TH, DO, BOD, COD, total coliforms, Escherichia coli, Ca2+, Mg2+, NO3−, and PO42−. Piper analysis indicated that water across the seven sampling zones along Indus River was alkaline in nature. Correlation analyses indicated that EC, TDS, TS, TH, DO, BOD, and COD may be considered as key physical parameters, while Na+, K+, Ca2+, Mg2+, Cl−, F−, NO3−, PO42−, and SO42− as key chemical parameters determining water quality, because they were strongly correlated (r > 0.70) with most of the parameters studied. Cluster analysis indicated that discharge point at Shami Road is the major source of pollution impairing water quality of Indus River. Wastewater treatment plants must be installed at all discharge points along Indus River for protecting the quality of water of this rich freshwater resource in Pakistan.

1,1-Ethylboration of Di(alkyn-1-yl)silanes with Two and Three Si-H Functions. New Silacyclopentadienes

The reaction of the di(alkyn-1-yl)silanes Me2Si(C≡CSiMe2H)2 1a and Me(H)Si(C≡CSiMe2H)2 1b with triethylborane was studied. In the case of 1a, the 4-ethyl-3-diethylboryl-1,1-dimethyl-2,5- bis(dimethylsilyl)-1-sila-2,4-cyclop entadiene 2a was the sole product. In the case of 1b, the analogous silole 2b was formed along with two other products which were identified as di(alkenyl)silanes 3b and 4b, in which different types of electron-deficient Si-H-B bridges could be detected. All products were characterised by consistent sets of solution NMR data (1H, 11B, 13C and 29Si NMR). The coupling constants 1J(13C,13C) were measured for 2a and calculated by using DFT methods (B3LYP/6-311+G(d,p) level of theory)