Self-assembled Transition Metal Coordination Frameworks of ...

g g 7 g Self-Assembled Transition Metal Coordination
further be used as a substrate for further complexation or to design mixed-metal
complexes. The complexes reported here possess uncoordinated donor atoms and this
is better in complexes derived from di-2-pyridyl ketone derived ligands. Accidentally
and fortunately complex la, got crystallized from a solution of complex 1, is found to
have two trapped water molecules inside the four uncoordinated pyridyl groups. This
kind of water of crystallization as a receptee and associated hydrogen bonds are
supramolecularly very potent.
The pyridyl group, selected here, is a very vital substituent in the light of
various biological activities shown by thiosemicarbazone and other related potential
compounds possessing it. Similarly, quinoline group, an equivalent analogue thereof,
also has a unique position in drug chemistry. So we found it worthwhile to go for an
immediate direction towards pharmaceutical applications. Also there was anticipation
of anticancer drug analogues for thiocarbohydrazones. In the light of these aspects we
carried out preliminary anticancer studies of selected compounds and included in the
thesis. The chapter wise conclusions of the thesis are as described below.
Chapter 1 depicts a brief survey of the previous research works in the field of
carbohydrazones and thiocarbohydrazones, their applications, importance of
multinuclear coordination compounds, method of self-assembly and
metallosupramolecular squares. The thiocarbohydrazone ligands possessing mainly
two binding units, unlike thiosemicarbazones, are found to have the possibility of
forming multinuclear compounds and for behaving as building blocks for self­
assembly to form molecular square grids. The different analytical and spectroscopic
techniques used for the analysis of the ligands and metal complexes are also
discussed.
Chapter 2 includes syntheses of carbohydrazone, thiocarbohydrazone and
thiosemicarbazone ligands and their spectral characterization by elemental analysis,
IR, UV-vis and different NMR techniques with a comparative study. X-Ray crystal
structures of two new ligands HZL3 and HZL-4 are also reported. All compounds were
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