Add double bond at C1. Add a C16 methyl group. A methyl group added to either the a or b face increases glucocorticoid activity and decreases mineralcorticoid activity for overall increased selectivity. Combinations of modifications which optimize antiinflammatory activity Betamethasone has 25 times and dexamethasone has 30 times the activity of cortisol. Triamcinolone, with a hydroxyl instead of a methyl group, has a shorter duration of action than betamethasone and dexamethasone, but is roughly as potent.
None have mineralcorticoid activity.
Aldosterone antagonists Aldosterone antagonists are useful for treating hypertension and refractory edema. Such a change produces an aldosterone antagonist without the unwanted antiandrogen side effects. Mechanism of action to decrease inflammation is by suppression of migration of polynorphonuclear leukocytes and reversal of increased capillary permeability. MOA as for cortisone. Can be given i.v.