ACS Chemical Abstracts Service (CAS)

CAS is a division of the American Chemical Society and the world's most authoritative source of chemical substance information. CAS provides the most comprehensive databases of disclosed research in chemistry and related sciences, including the world's largest collection of disclosed substance information, CAS REGISTRY℠.

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  • CAS makes this information available to researchers through SciFinder® and STN®, the pre-eminent search and retrieval tools for scientists and information professionals.

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  • CAS databases, updated daily, include the CAS REGISTRY with more than 85 million substances and CAS Registry Number® identifiers, CAplus℠ with indexed references from more than 10,000 major scientific journals and 63 patent authorities around the world, and CASREACT® with more than 58.4 million single- and multi-step reactions and more than 13.4 million synthetic preparations.

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  • SciFinder® is the leading research tool that allows scientists to quickly explore the CAS databases containing the highest quality and most comprehensive collection of chemistry and related scientific information from around the world.

  • STN® is the world leader in providing global access to the most accurate, timely and comprehensive scientific, technical and patent information.

  • Common Chemistry™ is a free, web-based resource that provides information on approximately 7,900 chemicals of widespread and general interest, as well as all 118 elements from the periodic table.

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  • CAS - Science Connections is a series of articles that showcases the value of CAS databases in light of important general-interest, science, and technology news and highlights CAS database enhancements and editorial milestones.

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