SPRESI Reaction Database
SPRESI Reaction Database Provided by the All-Union Institute of Scientific and Technical Information of the Academy of Sciences of the USSR (VINITI) and the German Zentrale Informationsverarbeitung Chemie, Berlin (ZIC). SPRESI is a web searchable database of 3.3 million compounds and 2.5 million reactions. Searching by exact structure, substructure and structural "similarity" are available. Reactions are displayed as part of the compound record. You get to draw your own structure. Pay per use.