Strucutres (II-IV) are analgues of a lead compound containg an aromatic ring (structure I). Strucutres II and III had increased similar activity to the lead compound whereas strucutre IV showed a moared increase in activity. Which of the following explainations best fits the facts?
a. Introducing a nitrogen increased the basicity and so increased basicity is good for activity
b. Intoducing a nitrogen increases the polarity and water solubility of the analogues and so increased polarity is good for activity
c. Introducing a nitrogen means that an additionaly hydrogen bonding interaction is possible with an extra bidning region in the binding site
d. Introducing a nitrogen removes an aromatic hydrogen. The aromatic hydrogen removed may have been bad for activity for steric reasons
Answer: C
Chemistry
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