PubChem is an open chemistry database at the National Institutes of Health (NIH). PubChem mostly contains small molecules, but also larger molecules such as nucleotides, carbohydrates, lipids, peptides, and chemically-modified macromolecules. Pubchem collects information on chemical structures, identifiers, chemical and physical properties, biological activities, patents, health, safety, toxicity data, and more. Search chemicals by name, molecular formula, structure, and other identifiers.
Chemical database is a dictionary of over 400,000 chemicals (names, synonyms, and structures). ChemIDplus includes links to NLM and other databases and resources, including links to federal, state and international agencies. ChemIDplus Lite is designed for simple searching on name or registry. ChemIDplus Advanced helps users draw their own structures and perform similarity and substructure searches.
"TRC is CHDR's freely available clinical pharmacology platform that provides users with quick and easy access to all available information on medicines, including clear overviews of pharmacological mechanisms of action."