Introduction

Using CA on CD's Formula Hierarchy you can

• Retrieve all references citing a substance on the CA on CD database
• Identify a substance name to combine with other search terms in Word Search

When to Use

Use the Formula Hierarchy to locate

• A substance based on its molecular formula and structural information contained in its name
• A family of structurally related substances

Definition

The Formula Hierarchy is a list of molecular formulas leading to substance names in a hierarchical organization based on chemical structure.

Example

Find references on the current CA on CD database to 4-(acetylamino) benzoic acid: molecular formula = C₉H₉NO₃.

How to

1. From the tool bar, click .

The Formula Hierarchy window is displayed.

2. Type the molecular formula in the Find entry box.

As you type, the list scrolls to display entries around the formula of interest. This is Level 1 of the Formula Hierarchy.

3. Click on the molecular formula of interest. Click .

4. Level 2 of the Formula Hierarchy for the molecular formula of interest is displayed.

Click on a substance name of interest.  

Click	To display	Proceed to
	Level 3 of the hierarchy	Step 5
	Molecular formulas in Level 1	Step 3

If the entry is	Click	To display	Proceed to
Preceded by a +		The next level of the hierarchy	Step 6
		The preceding level of the hierarchy	Step 4
Preceded by a -		The preceding level of the hierarchy	Step 4
Followed by a CAS RN in brackets (e.g., [3880-99-7])		A list of reference titles citing the substance	Step 8
		A reference, if there is only one, citing the substance

8. Click

To display the	Then
Next record	Click Next
Previous record	Click Previous
List of document titles	Close the Record window to reveal the Search Results window behind it: Hold down the Ctrl key Strike the F4 key Note: If more than one record has been displayed, repeat Steps 1 and 2 to close each Record window.