This compound is a pyrazole, a five-membered aromatic ring with adjacent nitrogens at positions 1 and 2. At position 1, the nitrogen bears an ethyl group. At position 4, the carbon is bonded to a sulfonyl group (S double-bonded to two oxygens -S(=O)2) that is also bonded to a nitrogen, which in turn is connected via a methylene to a phenyl ring para-substituted by a tert-butyl group (-C(CH3)3).