Ligand profile

HQO

Ligand co-crystallized with a similar protein (Protein Data Bank).

Bound to: KP13_31481 — Fumarate reductase flavoprotein subunit

Via homolog PDB 1kf6 UniProt P00363 Formula C₁₆H₂₁NO₂
Mol. weight 259.35 Da
Permeability High
PAINS Alert

Identifiers

Database identifiers and provenance.

Ligand ID
HQO
PDB
1kf6
UniProt (similar protein)
P00363
Target protein
KP13_31481

Structure

2D representation rendered from SMILES.

Physicochemical properties

Computed with RDKit from SMILES.

Molecular weight 259.35 Da
LogP (Crippen) 3.69
H-bond donors 1
H-bond acceptors 2
TPSA 47.17 Ų
Rotatable bonds 6
Aromatic rings 2 / 2
Heavy atoms 19
Fraction sp³ C 0.44
Formula C₁₆H₂₁NO₂

Drug-likeness

Descriptor-based ADME screening flags from SMILES. These are not experimental toxicity results.

Permeability proxy High

Estimated from TPSA and LogP only: TPSA ≤ 90 Ų and −1 ≤ LogP ≤ 5 are treated as a favorable small-molecule permeability screen.

  • TPSA ≤ 90 Ų 47.2
  • −1 ≤ LogP ≤ 5 3.69
Lipinski's Rule of Five Pass 0 violations
  • MW ≤ 500 Da 259.3
  • LogP ≤ 5 3.69
  • H-bond donors ≤ 5 1
  • H-bond acceptors ≤ 10 2
Veber's rules Pass
  • Rotatable bonds ≤ 10 6
  • TPSA ≤ 140 Ų 47.2
PAINS Alert

Matches PAINS filter: het_pyridiniums_A(39). May be a frequent false positive in HTS — review carefully.

Chemical representations

Canonical representations for cheminformatics workflows.

SMILES 
CCCCCCCc1cc(c2ccccc2[n+]1[O-])O
InChI 
InChI=1S/C16H21NO2/c1-2-3-4-5-6-9-13-12-16(18)14-10-7-8-11-15(14)17(13)19/h7-8,10-12,18H,2-6,9H2,1H3
InChIKey 
NZPACTGCRWDXCJ-UHFFFAOYSA-N

Provenance

Annotation context from LigQ_2, the internal Target step that collects PDB, ChEMBL, and ZINC ligand evidence.

Method
LigQ sequence
Source
PDB
Binding sites
PF02300' 'PF02313' 'PF13237

External resources

Open this ligand in third-party databases and cheminformatics tools.

Other ligands for this protein

Quick navigation to other ligands bound to KP13_31481.

PDB 35

Ligands co-crystallized with this protein (structural evidence).

Ligand PDB entry

ZINC 50

Virtual screening candidates selected by structural similarity to known actives (Tanimoto ≥ 0.5).

Compound Similarity (Tanimoto)