Sulfoximines: A Neglected Opportunity in Medicinal Chemistry

Innovation has frequently been described as the key to drug discovery. However, in the daily routine, medicinal chemists often tend to stick to the functional groups and structural elements they know and love. Blockbuster cancer drug Velcade (bortezomib), for example, was rejected by more than 50 companies, supposedly because of its unusual boronic acid function (as often repeated: "only a moron would put boron in a drug!"). Similarly, in the discovery process of the pan-CDK inhibitor BAY 1000394, the unconventional proposal to introduce a sulfoximine group into the lead series also led to sneers and raised eyebrows, since sulfoximines have seldom been used in medicinal chemistry. However, it was the…