[Chimera-users] building a molecule in Chimera

[Elaine Meng]

Hi Mike,
There is no quick 2D sketching to create a small molecule, only building it up atom-by-atom.  You can also enter a SMILES string or specify a PubChem CID to generate a small molecule in Chimera, which could be used as a starting point for further atom-by-atom building if necessary.  It's easier than building the whole thing atom by atom. If you don't want to deal with SMILES, you can search PubChem Compound to find the CID number of your molecule or a similar molecule to use as a starting point.  <http://www.ncbi.nlm.nih.gov/pccompound>

These options are all with the Build Structure tool (in menu under Tools… Structure Editing).  See the Start Structure and Modify Structure sections in that tool.
<http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.html>

For example, after starting Build Structure in Chimera, in its Start Structure section you could enter 

SMILES string:  c1ccccc1OC
or
PubChem CID:  31231

… and click Apply to get the specified molecule.  Then you could Ctrl-click one of the hydrogens to select it and change it to bromine using the Modify Structure section of Build Stucture (Element: Br, Bonds: 1, click Apply).  Or you could change it to a methyl group (Element: C, Bonds:4, Geometry: tetrahedral, Apply) and then select one of the hydrogens on the new methyl group to continue building out further.

I hope this helps,
Elaine
----------
Elaine C. Meng, Ph.D. 
UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab
Department of Pharmaceutical Chemistry
University of California, San Francisco

On Jan 10, 2015, at 2:01 PM, "Mike" <mikej at nc.rr.com> wrote:

> This is my first day with Chimera.  I’m trying to find how to draw a small molecule, minimize the structure of the small molecule and then
> have it interact with my protein of interest.  However, I don’t see any way for me to draw a small molecule (potential drug).
> Can you provide any direction ?
>  
> Thanks,
> Mike