Betaine Salicylate
Formula: C12H17NO5
Molecular Weight: 255.27
Antimicrobial, Exfoliator

The combination of famous exfoliant, salicylic acid and gentle moisturizer, betaine. It counts as a mild exfoliant and natural moisturizer, skin smoothing agent.
You usually find this guy in K-Beauty products, as due to regulations, pure salicylic acid can be used only in tiny amounts in South-Korean formulations. A generally accepted ballpark number is that betaine salicylate is twice as gentle as salicylic acid, i.e. a 4% betaine salicylate product is similar to a 2% salicylic acid one.