f the query is a phrase or a name with non-alphanumeric characters, double quotes should be used around the query. 

http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pccompound (for Compound) http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pcsubstance (for Substance) http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pcassay (for BioAssay).  

retrieved in the XML format, using the eInfo functionality in E-Utilities (which will be covered in Module 7):

For numeric indices, a search for a range of values can be done by using minimum and maximum values separated by a colon and followed by the bracketed index name (e.g., “100:105[MolecularWeight]”).

FLink tool

However, some special filters, such as the "lipinski rule of 5" filter, or the “all” filter, are not link-based.

The Entrez Search and Retrieval System

In practice, the identifier exchange service may be used as a quick approach to search the PubChem Compound database using multiple queries, although this type of task may be performed programmatically (for example, using PUG-REST,10 which will be discussed in Module 7).

3.2. Identifier Exchange Service

“[synonym]” index returns additional 97 compounds. 

MeSH Synonyms

1.2.6. Entrez History

Entrez links are cross links or associations between records in different Entrez databases, or within the same database.  These links may be applied to an entire search result list (via the “find related data” section at the right column of a DocSum page) or to an individual record (via links at the bottom of each record presented on the DocSum page).  The Entrez links provide a way to discover relevant information in other Entrez databases based on a user’s specific interests.  Equivalently, one may think of this as a way to transform an identifier list from one database to another based on a particular criterion. Note that there are limits to how many records may be used as input in a link operation.  To process a large amount of input records and/or to expect a large amount of output records associated with the input records, one should use the FLink tool (https://www.ncbi.nlm.nih.gov/Structure/flink/flink.cgi).         A complete list of the Entrez links available for the three PubChem databases can be retrieved in the XML format through these links http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pccompound (for Compound) http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pcsubstance (for Substance) http://eutils.ncbi.nlm.nih.gov/entrez/eutils/einfo.fcgi?db=pcassay (for BioAssay).  

MeSH (Medical Subject Headings)

PubChem Compound:

why the “legacy” designation was introduced in PubChem

Synonyms

BioAssay classification tool

Cameo ChemicalsResearch and Development, Governmental Organizations, Curation Efforts

The listed chemicals are safer alternatives, grouped by their functional-use class.

The input list can be provided by text, a file, or Entrez history. Registry IDs, SIDs, CIDs, InChIKey, and SMILES can be separated by white space, comma, tab, or carriage return, however InChI and Synonyms should be separated by tab or carriage return only. If Registry IDs are provided, the Registry Source Name must also be provided.

Lead-like

Components of the rule

Rule of five" redirects here. For the rule of thumb as it applies to the C++11 programming language, see Rule of three (C++ programming). Lipinski's rule of five also known as the Pfizer's rule of five or simply the Rule of five (RO5) is a rule of thumb to evaluate druglikeness or determine if a chemical compound with a certain pharmacological or biological activity has properties that would make it a likely orally active drug in humans. The rule was formulated by Christopher A. Lipinski in 1997, based on the observation that most orally administered drugs are relatively small and moderately lipophilic molecules.[1][2] The rule describes molecular properties important for a drug's pharmacokinetics in the human body, including their absorption, distribution, metabolism, and excretion ("ADME"). However, the rule does not predict if a compound is pharmacologically active.

Partition coefficient log P in −0.4 to +5.6 range

In analogy to the rule of five, it has been proposed that ideal fragments should follow the 'rule of three' (molecular weight < 300, ClogP < 3, the number of hydrogen bond donors and acceptors each should be < 3 and the number of rotatable bonds should be < 3).[1] Since the fragments have relatively low affinity for their targets, they must have high water solubility so that they can be screened at higher concentrations.

Entrez Nodes Are Intended for Linking

An Entrez "node" is a collection of data that is grouped together and indexed together

For example, a well-annotated SWISS-PROT record for a particular protein may have fields that describe other protein or GenBank records from which it was derived.

Biomolecular Interactions and Pathways

wwPDB data centers serve as deposition, annotation, and distribution sites of the PDB archive. Each site offers tools for searching, visualizing, and analyzing PDB data. PDBe Protein Data Bank in Europe Rich information about all PDB entries, multiple search and browse facilities, advanced services including PDBePISA, PDBeFold and PDBeMotif, advanced visualisation and validation of NMR and EM structures, tools for bioinformaticians.

Since 1971, the Protein Data Bank archive (PDB) has served as the single repository of information about the 3D structures of proteins, nucleic acids, and complex assemblies. The Worldwide PDB (wwPDB) organization manages the PDB archive and ensures that the PDB is freely and publicly available to the global community. Learn more about PDB HISTORY and FUTURE.

DrugBank CAMEO Chemicals The National Institute for Occupational Safety and Health - NIOSH HSDB ILO-ICSC Human Metabolome Database OSHA Chemical Sampling Information OSHA Occupational Chemical DB NIOSH-PocketGuide

The E-utilities are therefore the structured interface to the Entrez system