Molecular Modification - Reversibly and Irreversibly Attached Groups

Reversibly and Irreversibly Attached Groups

The type of group selected also depends on the degree of permanency required. Groups that are bound directly to the carbon skeleton of the lead compound by less reactive C–C, C–O and C–N bonds are likely to be irreversibly attached to the lead structure.

Groups that are linked to the lead by ester, amide, phosphate, sulfate and glycosidic bonds are more likely to be metabolized from the resulting analogue to reform the parent lead compound as the analogue is transferred from its point of administration to its site of action. Compounds with this type of solubilizing group are acting as prodrugs and so their activity is more likely to be the same as the parent lead compound. However, the rate of loss of the solubilizing group will depend on the nature of the transfer route, and this could affect the activity of the drug.