ScienceDirect has non-ACS chemistry journals as well as interdisciplinary journals related to chemistry. This site also has e-books available.
Includes over 2,000 journals and 35,000 books published by Elsevier Science and its subsidiary publishers, including Academic Press, Cell Press, Pergamon, Mosby, and Saunders journals. Coverage is particularly strong for the life and physical sciences, medicine, and technical fields, but also includes some social sciences and humanities.
Includes chemistry, chemical engineering, clinical medicine, computer science, earth & planetary sciences, economics, engineering, energy & technology, environmental science & technology, life sciences, materials science, mathematics, physics, astronomy.
SpringerLink has applied chemistry journals. This site also has e-books which can be downloaded by chapter or the entirety of the book.
Personal copies of some books can be purchased for $39.99 each through a service offered by Springer called MyCopy. The MyCopy offer is currently valid for over 14,000 Springer eBooks. More info about MyCopy.
Entire content of the print edition of the CRC Handbook. Contains frequently used data in science, including the periodical table of the elements, basic constants and units, and geophysical data. Updated annually.
From the National Library of Medicine, this collection of information "provides references covering the biochemical, pharmacological, physiological, and toxicological effects of drugs and other chemicals." This is mostly citations instead of full text articles. Coverage goes back to 1999.
This database has over 39 million chemical reactions. You can search by drawing in chemical structures and then limiting to reagent, solvent, etc. Java has to be enabled to use the drawing function.
Combined web access to Beilstein, Gmelin, and Patent Chemistry Database. Search by chemical structures or reactions to retrieve physical/chemical properties, spectra, related reactions, description of reactions as well as references to the literature in which the data appear. It also includes the synthesis planner tool.
Merck Index is a reference tool that contains short entries on various compounds including drugs. The entries will contain CAS registry number, synonyms of the substances, chemical formula, molecular weight, various physical properties, and references to further information about that substance.