CAS REGISTRY®, the CAS substance collection, is the premier source relied upon by scientists and regulators worldwide for accurate information on chemical substances.

CAS Registry Numbers (CAS RN) are simple and regular, convenient for database searches. They offer a reliable, common and international link to every specific substance across the various …

“CAS registry” is a registered trademark of the American Chemical society.

Dec 16, 2025 · You can also identify your substance of interest by its CAS Registry Number®, which is universally used to provide a unique, unmistakable identifier for chemical substances.

Each number represents only one substance and has no chemical significance but serves solely as an internationally observed substance identifier by scientists, industry and regulatory organizations.

2 days ago · CAS registry numbers are used for searching chemical databases. The size of the registry is immense, with over 32 million substances and 59 million sequences. It identifies every chemical …

Building blocks refer to a class of basic units used to synthesize complex compounds with specific activities. Common molecular structural units in organic chemistry include: carbon-based structural …

6 days ago · The CAS reference collection aggregates and connects scientific knowledge from thousands of journals and other sources published globally in more than 50 languages dating back to …

Provider of Discovery CRO, compound sourcing, and computational chemistry services to support your pharmaceutical research and development needs.

CAS (Chemical Abstracts Service) is a division of the American Chemical Society. It is a source of chemical information and is located in Columbus, Ohio, United States.