TABLE OF CONTENTS

A new ligand, Se (CH2-N-Btrzole)2 and its cobalt(II) complex, Co(L^se)2·(SCN)2, have been synthesized and the molecular been determined by X-ray techniques. The ligand Lse presents very good SOD activity.

Both NMR spectra and UV-vis titration data have showed that GMP coordinates via guanine base to thallium(I) ion in the pH range of study (1.5-10). The formation constants at different media were analyzed in terms ofamlet and Taft's parameters. In this work, we have also used the normalized polarity parameter, E_T^N, alone and in combination with some of theamlet-Taft parameters to find a better correlation of the formation constants at different aqueous solutions of methanol.

The Ce(III), La(III) and Nd(III) complexes of coumarin-3-carboxylic acid were synthesized and determined by means of spectral data (IR, Raman), TGA and elemental analysis. The newly synthesized compounds were assayed for cytotoxicity against SKW-3, HL-60 and Reh cells. The complex of neodymium(III) induced approximately 50% reduction of the survival HL-60 and SKW-3 cells at concentration 200 µM.

The Br/Li exchange was applied to gen-erate an ortho-lithiated derivative of protected phenylboronic acid. This intermediate was quenched with electrophiles to give various ortho-functionalized arylboronic acids and 1,3-dihydro-1-hydroxy-3-arylbenzo[c][2,1]oxaboroles; one of these compounds was characterized by X-ray diffraction

The presence was established of tributyltin, dibutyltin and monobutyltin in outdoor settled dust collected from several sites on the island of Malta. Concentrations as high as 15.5 and 18.7 µg Sn g^-1 were determined in certain areas. The distribution of these contaminants suggests that organotins originate mainly from marine paint removal work in Grand Harbour and the municipal solid waste landfill at Maghtab and the higher levels of contamination may be of concern for the health of young children.

The solution behaviour of both the Zn(HDz)₂ photochromic complex and the H₂Dz ligand was investigated by Vis spectroscopy, advanced NMR techniques and Density Functional calculations. This theoretical and experimental approach has enabled to shed light on the structure and bonding of both the stable and activated complex forms involved in the photochromic equilibrium. These results disclose interesting perspectives for the inclusion of Zn(HDz)₂ in transparent oxide matrices aimed at the development of advanced optical devices. Molecular structure of Zn(HDz)₂

The complexes [Rh(CO)₂ClL](1), where L = 2-aminophenol (a), 3-aminophenol (b) and 4-aminophenol (c), have been synthesized and characterized. The ligands are coordinated to the metal centre through an N-donor site. The complexes 1 undergo oxidative addition (OA) reactions with various alkyl halides (RX) like CH₃I, C₂H₅I and C₆H₅CH₂Cl to produce Rh(III) complexes of the type [Rh(CO)(COR)XClL], where R = CH₃(2), C₂H₅(3), X = I; R = C₆H₅CH₂ and X = Cl (4). The OA reaction with CH₃I follows a two-stageinetics and shows the order of reactivity as 1b > 1c > 1a. The minimum energy structure and Fukui function values of the complexes 1a-1c were calculated theoretically using a DND basis set with the help of Dmol³ program to substantiate the observed local reactivity trend. The catalytic activity of the complexes 1 in carbonylation of methanol, in general, is higher (TON 1189-1456) than the species [Rh(CO)₂I₂]^- (TON 1159).

Without following tedious separation, in- situ prepared sodium ferrate oxidizes aromatic alcohols and aldehydes to their corresponding carbonyl compounds or aromatic acids, respectively, in excellent yields under microwave irradiation, when adsorbed on montmorillonite in the presence of copper nano-particles. Aromatics with amino or hydroxy groups polymerize.

Three substituted salicylaldimine ligands (1a, 2a, 3a) and their titanium complexes bis[N-(5-nitrosalicylidene)-2,6-disopropylanilinato]titanium(IV)dichloride (1), bis[N-(5-chlorosalicylidene)-2,6-diisopropylanilinato]titanium(IV)dichloride (2) and bis[N-(5-bromosalicylidene)-2,6-diisopropylanilinato]titanium(IV)dichloride (3) were synthesized? characterized and used as catalysts for ethylene polymerization in the presence of MAO .Their catalytic activities are much higher than that of corresponding complex with no substituent in the 5-position of the salicylaldiminato ring. All these complexes are favorable for producing polyolefins with a broad molecular weight distribution and high melting points

Multiwalled carbon nanotubes have been synthesized by the floating catalyst method using toluene as the carbon source and mixtures of ferrocene and ferrocenyl sulfide as the catalyst.

N,N,N,N,N-pentamethyl-N-(trifluorosilylmethyl)phosphoric triamide exists in (OSi)chelate form with intramolecular PO Si coordination bond.

New oxorhenium complexes with 3-methylazapentane-1, 5-dithiolate (SNMeS) and thiol functionalized monodentate tetrahydroquinolyl and tetrahydroisoquinolyl derivatives, namely THQ (CH₂)₂SReO (SNMeS) and THiQ (CH₂)₂SReO (SNMeS), have been synthesized. The characterization of complexes involved elemental analysis, IR, ¹H and ¹³C NMR spectroscopy and X-ray crystallographic analysis. Metal complexes were found to be active in psychotropic in vivo and cytotoxicity in vitro screening.

A new series of antibacterial and antifun-gal amino acid derived Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments, IR and electronic spectral measurements. The synthesized ligands, along with their metal complexes, were screened for their in-vitro antibacterial activity against four Gram-negative (Escherichia coli, Shigella flexeneri, Pseudomonas aeruginosa and Salmonella typhi) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains and for in-vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata