Anti-inflammatory steroids structure-activity relationship

Structure-Activity Relationship (SAR) Intensive and extensive clinical investigations have duly revealed that the anti-inflammatory activity emanated by the adrenal cortical steroids in humans invariably correlates intimately with their respective glucocorticoid activity. The advent of glaring and outstanding researches have evolved several synthetic steroids that exclusively possess distinctly higher glucocorticoid, and relatively lower mineralocorticosteroid activity in comparison to cortisone or cortisol that have been duly prepared, biologically screened, and marketed. 

Bodor N, Harget AJ, Phillips EW. Structure-activity relationships in the anti-inflammatory steroids a pattern-recognition approach. J Med Chem 1983 26 318-333. 

In connection with the work on the relationship between chemical structure and anti-inflammatory activity, the effect of ursolic acid, betulin, betulinic acid and erythrodiol on a system of chronic dermal edema and cellular proliferation caused by repeated administration of TPA has recently been examined [89], This experimental model of chronic inflammation has considerable selectivity for corticosteroids and leukotriene synthesis inhibitors. Erythrodiol and ursolic acid were significantly effective and also reduced the neutrophil infiltration detected by MPO activity. The lupane derivatives, betulin and betulinic acid, despite their possible steroid-like mechanism of action [47], were not effective in the chronic model. This result could mean that a six-member E ring of the pentacyclic structure is necessary for the activity against a multiple dose of TPA. The data confirm that a hydroxyl group at the C-28 position is important for the activity, as is also true in the case of erythrodiol, and it may explain the anti-inflammatory effect of this compound in each of the methods. 

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