Moazzam H. Bhatti

Synthesis, spectroscopic characterization, crystal structure and antifungal activity of thiourea derivatives containing a thiazole moiety

AbstractFour novel thiourea derivatives containing a thiazole moiety were synthesized and characterized by IR, 1H and 13C NMR, mass spectrometry and elemental analysis. The crystal structure of 1a was determined from single crystal X-ray diffraction data. It crystallizes in monoclinic space group P21/n with unit cell dimensions a = 11.7752(6) Å, b= 3.8677(2) Å, c= 27.4126(13) Å and β = 92.734(5) Å. There is a strong intramolecular hydrogen bond of the type N-H⋯O, with H⋯O distance of 2.5869(19) Å. The mass fragmentation pattern has also been discussed. The antifungal activity of the synthesized compounds was studied by broth micro-dilution method and poisoned food technique. The compounds 1b and 1c possessed a broad spectrum of antifungal activity.

Synthesis, Spectroscopic Characterization and Biological Studies of Organotin Derivatives of 2- (2,6-dichlorophenyl)aminophenylaceticacid

Abstract Infrared, multinuclear NMR, mass and Mössbauer spectral techniques have been used to characterize new organotin compounds of 2-(2,6-dichlorophenyl)aminophenyl-acetic acid anion with the general formulae R3SnL, R2SnL2 and R2Sn(Cl)L where R = CH3, C4H9, C6H5, C6H5CH2 and L = 2-(2,6-dichlorophenyl)-aminophenylacetic acid anion. These techniques were used to compare the geometry of these compounds as solids and in solution. Antibacterial and antifungal activities were determined in order to study their biological significance.

Reactivity of some poly-1-alkynylsilicon and -tin compounds towards triallylborane—routes to novel heterocycles

Abstract Triallylborane reacts with most poly-1-alkynylsilanes ( 1 – 5 ), containing up to four CC units, or di(1-alkynyl)tin compounds ( 6 ) to give either siloles ( 8 , 11 , 14 , 16 ), as the result of an intermolecular 1,1-allylboration followed by an intramolecular 1,1-vinylboration, or the novel 2-alkylidene-1,3-silaborolene ( 9 ) or 2-alkylidene1,3-stannaborolene derivatives ( 17 ), as the result of intermolecular 1,1-allylboration followed by an intramolecular 1,2-allylboration. In the case of the borolene derivatives, a second intramolecular 1,2-allylboration takes place to give 1,7-borasila- or 1,7-borastannabicyclo[4.3.0]nona-5,8-diene derivatives ( 10 , 12 , 13 , 15 , 18 ). If the starting materials are di(1-alkynyl)methylsilicon hydrides ( 2 ), the latter reaction affords selectively only one diastereomer ( 10 ( H )). All products were characterised by extensive multinuclear magnetic resonance spectra ( 1 H-, 11 B-, 13 C-, 29 Si-, and 119 Sn-NMR).

Electrochemical and spectroscopic investigations of carboxylic acid ligand and its triorganotin complexes for their binding with ds.DNA: in vitro biological studies.

A carboxylic acid ligand, (Z)-4-(4-acetylphenylamino)-4-oxobut-2-enoic acid (APA-1), and its triphenyl-(APA-2) and tributyl-tin(IV) (APA-3) compounds have been synthesized and investigated for their binding with ds.DNA using UV-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and viscosity measurements under physiological conditions of pH and temperature. The experimental results from all techniques i.e. binding constant (Kb), binding site size (n) and free energy change (ΔG) were in good agreement and inferred spontaneous compound-DNA complexes formation via intercalation. Among all the compounds APA-3 showed comparatively greater binding at pH 4.7 as evident from its greater Kb values {APA-3: Kb: 5.63×10(4)M(-1) (UV); 7.94×10(4)M(-1) (fluorescence); 9.91×10(4)M(-1) (CV)}. Electrochemical processes of compounds before and after the addition of DNA were found diffusion controlled. Among all compounds, APA-3 exhibited best antitumor activity.

1H, 13C, AND 119Sn NMR, IR, MASS, THERMAL, AND BIOLOGICAL STUDIES OF ORGANOTIN(IV) DERIVATIVES OF 4-p-(CHLOROPHENYL)-2-PHENYL-5-THIAZOLEACETIC ACID

ABSTRACT A series of di- and triorganotin(IV) carboxylates of 4-p-(chlorophenyl)-2-phenyl-5-thiazoleacetic acid has been synthesized and characterized by various instrumental techniques such as infrared, 1H, 13C, 119Sn NMR, mass spectrometry and thermal analysis. These compounds were also tested for their antibacterial and antifungal activities to study their biological significance.

Hydroboration of alkyn-1-yl(methyl)silanes bearing functional substituents at silicon

Abstract Alkyn-1-yl(methyl)silanes Me2(H)Si–CC–R (1), Me(H)(Cl)Si–CC–R (2) and Me2(Cl)Si–CC–R (3) [R=Bu (a), tBu (b), Ph (c), SiMe3 (d)] react with 9-borabicyclo[3.3.1]nonane (9-BBN) by 1,2-cis-hydroboration to give selectively (except of 3d) the alkenylsilanes 4 (from 1), 5 (from 2), and 6 (from 3), in which the boryl group has become attached to the carbon atom adjacent to the silyl group bearing functional substituents. In the case of 3d, a mixture consisting of the alkenes 6d and the isomers 7d, 8d and 9d is obtained. All products were characterised by NMR spectra (1H-, 11B-, 13C- and 29Si-NMR) in solution, and in the cases of 5c and 6c, the molecular structures in the solid state were determined by X-ray analysis.

SYNTHESIS, SPECTROSCOPIC CHARACTERIZATION, AND BIOLOGICAL APPLICATIONS OF ORGANOTIN(IV) DERIVATIVES OF 2-(N-MALEOYL)-3-PHENYLPROPANOIC ACID

ABSTRACT In an effort to develop new organotin materials for investigation and biocidal evaluation, a series of compounds with the general formula R4−nSnLn (where R=CH3, n-C4H9, C6H5, C6H5CH2 and L=2-(N-maleoyl)-3-phenylpropanoic acid anion) have been synthesized, and characterized by elemental analyses, IR, multinuclear (1H, 13C and 119Sn) NMR and mass spectrometry. The biological activity of these compounds against various bacteria and fungi has been investigated. All of the compounds were found to be active against the tested fungi with a few exceptions. These compounds also showed significant antibacterial activity. LD50 data show that the investigated compounds also have significant toxicity.

Ethyl 4-(3-benzoyl-thio-ureido)benzoate.

The title compound, C17H16N2O3S, crystallizes in the thioamide form with an intramolecular N—H⋯O hydrogen bond across the thiourea system. Molecules are connected in chains parallel to [10] by hydrogen bonds from the second thiourea N—H group to the benzoate C=O function.

Ethyl 4-(3-butyrylthio-ureido)benzoate.

The title compound, C14H18N2O3S, crystallizes in the thioamide form with an intramolecular N—H⋯O hydrogen bond associated with the thiourea unit. With the benzoic acid and the butyrylthioureido units, the molecule consists of two planar building blocks connected by the common NH function adjacent to the aromatic ring. The interplanar angle is 33.38 (3)°. Molecules are connected in chains parallel to [110] by classical hydrogen bonds of the N—H⋯O type from the other NH group to the benzoate C=O of a neighboring molecule.

Organotin(IV) complexes of 4-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acid: Synthesis, spectral characterization and biological applications

Abstract4-(2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acid and its complexes with methyl-, n-butyl-, phenyl-, benzyl- and octyl-tin have been synthesized and characterized by elemental analysis and spectral studies. The geometry around the tin atom has been deduced from both solid and solution studies. These complexes were also tested against different bacteria and fungi to determine their toxicity. LD50 data was also calculated using the Brine Shrimp method.