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ACS News

CAS reaches 150 millionth substance

by Linda Wang
May 30, 2019 | A version of this story appeared in Volume 97, Issue 22


On May 8, CAS registered its 150 millionth unique chemical substance—a 2-pyrimidinamine carbonitrile derivative, one of several promising compounds studied as inhibitors of two kinases (TBK and IKK) implicated in cancer and immunological diseases, including rheumatoid arthritis, systemic lupus erythematosus, and lupus nephritis.

CAS, a division of the American Chemical Society, provides scientific information services such as SciFinder and patent searching.

The substance was disclosed in a Merck KGaA patent reported by the World Intellectual Property Organization. The full name of the compound, CAS Registry Number 2306877-20-1, is 2-[[3,3-difluoro-1-[(2R)-2-hydroxy-1-oxopropyl]-4-piperidinyl]oxy]-5-[2-[[5-[(2R)-2,4-dimethyl-1-piperazinyl]-6-methoxy-2-pyridinyl]amino]-4-pyrimidinyl]benzonitrile.

Gilles Georges, vice president of CAS content operations, says it’s important to celebrate such milestones. “We don’t want it to be just a number; it has significance in terms of where the research is going. It took us about 40 years to register the first 25 million substances, and we reached that in 2005. We have registered 50 million substances in the last 4 years. That really speaks to the acceleration of chemistry research globally.”

The CAS Registry, which identifies and aggregates chemical substance information, was established in 1965. It is now the world’s largest curated database of unique chemical substances.


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