COMPLEXATION AND PROTEIN BINDING Seletted Definitions • •
Complex compounds: Those molecules in which most bonding structures can be described by classical valence theories between atoms, but one or more of these bonds are somewhat anomalous. Complexation: It is the association between two or more molecules to form a non bonded entity with a welldefined stoichiometry
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Ligands: The ligand is a molecule that interacts with another molecule ( the substrate) by co-ordinate bonds and form a complex.
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Metal Complex: It consists of a central metal atom or ion that is bonded to one or more ligands.
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Coordination
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Chelatation: It is the process of formation of two or more separate coordinate bonds between a polydentate ligand and a single central atom.
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Inclusion complexes: These are the compounds in which one of the components is trapped in the open lattice or cage like crystal structure of the other. Clatharates: It is a cage like complex in which the coordinating compound is entrapped. Protein Binding: This is the phenomenon of complex formation of drugs with proteins
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Number: It is defined as the total number of ligands attached to a central metal ion/atom.
7. 1 INTRODUCTION Complex compounds are defined as those molecules in which most bonding structures can be described by classical valence theories between atoms, but one or more of these bonds are somewhat anomalous. Complexation is the association between two or more molecules to form a non bonded entity with a well-defined stoichiometry. In broad terms, complexation is used to characterize covalent or non-covalent interactions between two or more compounds that are capable of independent existence. The intermolecular forces involved in complex formation are the covalent bond, the vanderwall forces, the dipole-dipole interaction, and the hydrogen bond etc. Complexes are formed because of the donor acceptor mechanism. Donor is the neutral molecule or ion of non metallic substance that can donate the lone pair of electrons. Acceptor is the metallic ion or sometimes it might a neutral atom.