openmolecules.org

 
Home » DataWarrior » Cheminformatics » sp3 count
sp3 count [message #1369] Tue, 10 August 2021 00:22 Go to next message
mvamos is currently offline  mvamos
Messages: 24
Registered: January 2015
Location: US
Junior Member
I'm curious about the sp3-Atoms count from the Calculate Properties->Atom Counts section. Generally for fraction sp3 calculations, it's # of sp3 carbon atoms divided by total carbon atoms. The sp3-Atoms count from DW seems to over-count, just not sure what else it's including.

In the attached photo, for the compound I count 3 sp3 carbon atoms, but DW returns 5.

Feature request: it might be more useful for users if it calculated the fraction of sp3 carbons instead of just # of sp3 atoms, as it's common to report the fraction for druglike compounds.
https://pubs.acs.org/doi/10.1021/jm901241e

Thanks and keep up the good work!
  • Attachment: Untitled9.png
    (Size: 25.98KB, Downloaded 376 times)
Re: sp3 count [message #1370 is a reply to message #1369] Tue, 10 August 2021 22:24 Go to previous messageGo to next message
nbehrnd is currently offline  nbehrnd
Messages: 224
Registered: June 2019
Senior Member
Dear mvamos,

based on the SMILES string generated by DW for this very structure, yet submitted to RDKit (2020.09.4) suggests different programs assign sp3-hybridization differently. In the case of RDKit, including fluorine [sic!], a total of 6.

Norwid
  • Attachment: test_case.zip
    (Size: 140.57KB, Downloaded 353 times)
Re: sp3 count [message #1380 is a reply to message #1370] Thu, 19 August 2021 21:23 Go to previous messageGo to next message
thomas is currently offline  thomas
Messages: 715
Registered: June 2014
Senior Member
Dear Mvamos,

DataWarrior considers C,N,O,P,S as potential sp3 atoms. In your case the 2 oxygen atoms are considered to be sp3 in addition to the 3 obvious carbon atoms. I agree that an ether-oxygen doesn't contribute much to the 3D-shape of a molecule, but the same is true for an (sp3) methyl group. It is a formal number. sp3 fraction in carbon atoms is simple and I will add it...

Thomas
Re: sp3 count [message #1381 is a reply to message #1369] Fri, 20 August 2021 12:05 Go to previous message
thomas is currently offline  thomas
Messages: 715
Registered: June 2014
Senior Member
I just deployed an update with 'sp3-Carbon Fraction', which is the count of sp3 carbons devided by all carbons as proposed in the 'Escape from flatland' paper.
Previous Topic: Mean value in category function
Next Topic: Integration with KNIME or Python
Goto Forum:
  


Current Time: Sun Nov 24 03:22:37 CET 2024

Total time taken to generate the page: 0.03962 seconds