Free chemical structure search engine. Millions of public domain structures. Very fast substructure searching. Results link to data about these structures.
ChemSpider is a chemistry search engine built with the intention of aggregating and indexing chemical structures and their associated information into a single searchable repository and making it available to everybody, at no charge. ChemSp...
ChemExper is a company joining together the areas of chemistry, computer science and telecommunication. The ChemExper Chemical Directory is a free service that allows to find a chemical by its molecular formula, IUPAC name, common name, CAS...