What is the approach and binding of a drug to its target broadly dependent on?

If a drug reacts with a binding site and becomes permanently attached, what type of intermolecular bond has been formed?

What is the bond strength range of a covalent bond?

List the types of temporary intermolecular forces that can form between drugs and their targets?

If intermolecular forces such as dipole-dipole interactions are temporary, why don't molecules fall apart and dissociate?

If temporary interactions are possible between the drug and its target, what exists between the unbound and bound drug?

What factors determine the length of time that a drug remains at its target?

What is pharmacodynamics?

What is the strongest of the intermolecular bonds?

What is required of the two molecules between which an ionic/electrostatic bond forms?

With regard to electrostatic/ionic bonds: the strength of the interaction is inversely proportional to...

How does the nature of the environment in which the drug-target interaction is occurring affect ionic/electrostatic bonds?

The drop-off in ionic bonding strength with separation is less than in other intermolecular interactions. What does this mean for the order in which drug-target interactions occur?

What is the strength range of hydrogen bonds? What does the strength of the bond formed depend on?

In a pair of atoms that are hydrogen bonded, which is the hydrogen bond donor?

In a pair of atoms that are hydrogen bonded, which is the hydrogen bond acceptor?

So the hydrogen bond donor is usually the electronegative (δ-) atom that hydrogen is covalently bound to - here, this is the O atom of the water molecule. The hydrogen bond acceptor is the electronegative atom that receives the hydrogen bond - it is electron rich (δ-) and hence accepts the electrodeficient hydrogen (δ+).

If we consider the hydrogen bond donor, the hydrogen atom itself, and the hydrogen bond acceptor to be 'X, Y, and Z', what is the ideal angle between these three components to form the strongest hydrogen bonds?

Which are the two most common atoms involved as hydrogen bond acceptors in biological systems?

Several drugs and macromolecular targets contain a sulphur atom, which is also electronegative. Why is sulphur a weak hydrogen bond acceptor?

Fluorine is present in several drugs but despite being more electronegative than oxygen or nitrogen and having three lone pairs of electrons, it is a weak hydrogen bond acceptor. Why?

What determines the strength of a hydrogen bond acceptor?

List some hydrogen bond accepting groups commonly present in drugs and binding sites as neutral functional groups.

It has been proposed that the pi (π) systems present in alkynes and aromatic rings are regions of high electron density and can act as hydrogen bond acceptors. Why might they be weak hydrogen bond acceptors?

What is the bond strength of van der Waals interactions?

What aspects of molecules do van der Waals forces involve interactions between?

Which physicochemical property of atoms between molecules results in the formation of permanent dipole-dipole interactions?

What role do permanent dipole-dipole interactions play in the binding of a drug to its target?

What is an ion-dipole interaction?

Describe an example of an induced dipole moment.

What are repulsive interactions?

What is the importance of water in drug-target interactions?

What structural adjustments may need to be made to a drug molecule in order to reduce its energy of desolvation (removal of H2O)?

Next to a non-polar surface, water molecules are more ordered as they form stronger reactions with each other in order to avoid the non-polar region. What does this mean for entropy? What might change when a drug binds with its target on a non-polar surface?