ACD FAQFrequently asked questions about Daylight's HTML interface to ACD.
Why is there a special interface for ACD?The HTML interface to ACD is designed to make access as simple as possible, implementing a "what do you want -- here it is" interface. The end-user does not need to know about servers, database names, datatypes, datatrees, thesaurus-orientation, ambiguous cross-references, etc.
ACD mainly contains catalog entries: product names, purities, prices, &etc. This interface is designed to deliver this information quickly and reliably to users who do not need to be chemical information specialists.
ACD isn't unique in this respect: Daylight produces simplified interfaces for other databases also.
What can I ask for?You can specify any identifier in the database, specifically: SMILES, CAS numbers, ACD numbers, ACD (preferred) names, Catalog numbers, and Catalog names. Except in the case of SMILES, queries are case-, whitespace-, and punctuation-insensitive.
Doesn't it get confused between identifier types?No, the Thor (thesaurus-oriented retrieval) methodology used here is good at dealing with ambiguous identifiers (e.g., two chemicals with the same name). This interface even works correctly for identifiers such as "OCCN" which are both valid SMILES (ETHANOLAMINE) and catalog names (OCCN is Ihara's catalog name for 2-CHLOROBENZYL CYANIDE). All matching references are shown any time there is an ambiguity.
Is this the same database as the Fine Chemicals Directory?Sort of. The ACD database evolved from the FCD. The current version covers many more catalogs than FCD did, and it includes both bulk and fine chemicals.
Is this the same ACD database as sold by MDL?Yes. Each version (e.g., "95.1") is derived from the data copyrighted by MDL and is distributed under license with MDL.
Does the Daylight version contain all entries in the original?Yes, as nearly as possible. As distributed by MDL, ACD contains entries for substances with known structure, e.g., ADENOSINE, comprising 94% of the entries, and those with no known structure, e.g., BANANA POWDER, comprising 6% of the entries.
Can I do substructure and similarity searching?No. The current HTML interface is limited to looking up specific chemicals. However, catalog entries are shown for enantiomers, isotopes, and other isomers of the requested chemical.
How can I draw in a structure (rather than typing SMILES)?Your choice of an editor depends on the kind of machine on which you are working. This can be customized by editing the dcgi_env.sh file.
The product table depictions are hot. Why bother?Clicking on a depiction on a "ACD product table" page brings up the "Depict" (Interactive depiction of SMILES) page. Editing the SMILES on this page changes the picture but does not affect what data is shown when returning to the ACD interface.
Invoking the Depict page is simply a way of providing the SMILES for any structure in a cut-and-paste-able form.
Can product tables be sorted by something other than USD/g?No.
Why are "black-on-paper depictions" offered?Depending on how your computer system is set up, color-on-black graphics may not show up well when printed to monochromatic printers. The "black-on-paper" option produces nice output with most browser/printer combinations.
Can I save specific ACD pages as a bookmarks?Yes. Most users save the "Available Chemicals Directory" page as a bookmark to allow convenient access to this interface. You can also add specific "ACD product table" pages to your bookmark list: they will appear with the preferred ACD name, e.g., "ACD: ETHANOLAMINE". "ACD thesaurus lookup" pages are form results and can not be saved as bookmarks.
Is the complete ACD database available online?No, not at the current time. Our license with MDL permits online distribution only for demonstration purposes. Daylight can supply the ACD database and the software to deliver it from your own server. Hardware requirements are minimal for the HTML interface (a UNIX workstation and about 100 MB free disk space).
Where can I get more information?For general information about the ACD database and Daylight's products, click on the "Daylight Chemical Information Systems, Inc." link to the Daylight Chemical Information Systems, Inc.