Lecture 2 Functional groups - solubility and steric effects

water soluble functional groups properties

ability to ionize, ability to form hydrogen bonds, and acidic/basic functional groups

ability to ionize

If a functional group can become charged, it usually becomes much more water-soluble

ability to form hydrogen bonds

Functional groups containing atoms such as O and N can often form hydrogen bonds with water.

acidic/basic functional groups

are particularly important because they can gain or lose H⁺ depending on pH, which can create a charge

lipid soluble functional groups

incapable of ionizing and incapable of forming H bonds

esters can be viewed as

either water soluble or lipid soluble functional groups

steric hindrance

the size and shape of functional groups have on a drug's conformation and its ability to fit into and bind to its biological target

steric effects benefits

Increased Selectivity for its biological target
Enhanced binding interactions with its biological target
Favorable alteration of its rate of metabolism

Amino acids

Building blocks for some peptide-based drug molecules
Building blocks for proteins and enzymes

amino acid structure

alpha carbon attached to amino group (–NH₃⁺), carboxyl group (–COO⁻), hydrogen, and R group