"SciFinder-n, produced by Chemical Abstracts Service (CAS), is the most comprehensive database for the chemical literature, searchable by topic, author, substances by name or CAS Registry Number, or using the editor to draw chemical structures, substructures, or reactions."
Reaxys is a tool for the retrieval of information and data on chemical structures, reactions, and properties. It covers chemical compounds, reactions, properties, related bibliographic data, substance data with synthesis planning information, and experimental procedures from selected journals and patents. It can be searched in a number of ways, including by chemical structure, molecular formula, and physical property parameters.
HSDB content has been recently migrated to PubChem. Follow these steps to find HSDB content in PubChem.