Dear Kathleen, There are some simple building capabilities, see Tools... Structure Editing... Build Structure: http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.htm... Building from scratch is somewhat limited, in that it is more of a bond-by-bond accretion than sketching the molecule in quickly. After building, you could use Minimize Structure (also under Tools... Structure Editing) to clean up the structure. Instead of building from scratch, however, I'd recommend looking up a PubChem CID, if possible, or writing a SMILES string for your molecule. These are options in the "Add Atoms" tab of Build Structure. In those cases, the information is sent to a web server that sends back an already-minimized structure. http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.htm... With the server approach, you may not get the protonation state you want, but you could simply delete any unwanted hydrogens and if necessary, use the AddH tool to add hydrogens. AddH tries to generate protonation states reasonable near pH 7, whereas the server generally gives neutralized groups. http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/addh/addh.html Structures in Chimera can be saved as Mol2 with File... Save Mol2. If you want partial charges in the Mol2 output, you could use Add Charge before saving the file. http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/addcharge/addcharge... All the tools I mentioned are under Tools... Structure Editing in the menu. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. meng@cgl.ucsf.edu UCSF Computer Graphics Lab and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Jul 11, 2008, at 2:49 AM, Kathleen.Zocher@ernaehrung.uni-giessen.de wrote:

Dear Sir or Madam,

I`ve just one question concerning some special tools of Chimera. Is it possible to draw small molecules (ligands) within chimera? I can not find some information for this problem in the manual. For further docking experiments I just need a 3D-structure which is minimized (in a mol2 file). Many thanks in advance!

Sincerely yours

Kathleen Zocher