Esempio n. 1
0
int QueryMolecule::parseQueryAtom (QueryMolecule& qm, int aid, Array<int>& list) {
   QueryMolecule::Atom& qa = qm.getAtom(aid);
   QueryMolecule::Atom* qc = stripKnownAttrs(qa);
   if (qc != NULL && isNotAtom(*qc, ELEM_H))
      return QUERY_ATOM_A;
   bool notList = false;
   if (collectAtomList(qa, list, notList) || 
      (qa.type == QueryMolecule::OP_NOT && collectAtomList(*qa.child(0), list, notList) && !notList)) { // !notList is to check there's no double negation
      if (list.size() == 0)
         return -1;
      notList = notList || qa.type == QueryMolecule::OP_NOT;
      if (!notList && list.size() == 5 && list[0] == ELEM_F && list[1] == ELEM_Cl && list[2] == ELEM_Br && list[3] == ELEM_I && list[4] == ELEM_At)
         return QUERY_ATOM_X;
      if (notList && list.size() == 2 && ((list[0] == ELEM_C && list[1] == ELEM_H) || (list[0] == ELEM_H && list[1] == ELEM_C)))
         return QUERY_ATOM_Q;
      return notList ? QUERY_ATOM_NOTLIST : QUERY_ATOM_LIST;
   }
   return -1;
}
bool MoleculePiSystemsMatcher::_fixAtoms (QueryMolecule &query, const int *mapping)
{
   // Fix charges
   for (int qv = query.vertexBegin(); 
            qv != query.vertexEnd(); 
            qv = query.vertexNext(qv))
   {
      int v = mapping[qv];
      if (v < 0)
         continue; // Such vertex must be ignored

      int pi_system_idx = _atom_pi_system_idx[v];
      if (pi_system_idx == _NOT_IN_PI_SYSTEM)
         continue;

      _Pi_System &pi_system = _pi_systems[pi_system_idx];

      QueryMolecule::Atom &qatom = query.getAtom(qv);
      int pv = pi_system.inv_mapping[v];

      int charge = query.getAtomCharge(qv);
      if (charge != CHARGE_UNKNOWN)
      {
         bool ret = pi_system.localizer->fixAtomCharge(pv, charge);
         if (!ret)
            return false;
      } 
      else if (qatom.hasConstraint(QueryMolecule::ATOM_CHARGE))
         throw Error("Unsupported atom charge specified");

      int valence = query.getExplicitValence(qv);
      if (valence != -1)
      {
         bool ret = pi_system.localizer->fixAtomConnectivity(pv, valence);
         if (!ret)
            return false;
      }
      else if (qatom.hasConstraint(QueryMolecule::ATOM_VALENCE))
         throw Error("Unsupported atom charge specified");
   }
   return true;
}
Esempio n. 3
0
bool QueryMolecule::queryAtomIsRegular (QueryMolecule& qm, int aid) {
   QueryMolecule::Atom& qa = qm.getAtom(aid);
   QueryMolecule::Atom* qc = stripKnownAttrs(qa);
   return qc && qc->type == QueryMolecule::ATOM_NUMBER;
}
bool MoleculeSubstructureMatcher::_shouldUnfoldTargetHydrogens (QueryMolecule &query, bool is_fragment, bool disable_folding_query_h)
{
   int i, j;

   for (i = query.vertexBegin(); i != query.vertexEnd(); i = query.vertexNext(i))
   {
      // skip R-atoms
      if (query.isRSite(i))
         continue;

      if (query.possibleAtomNumberAndIsotope(i, ELEM_H, 0))
      {
         const Vertex &vertex = query.getVertex(i);

         // Degree 2 or higher => definilely not a hydrogen
         if (vertex.degree() > 1)
            continue;

         // Can be lone hydrogen?
         if (vertex.degree() == 0)
            return true;

         // degree is 1 at this point
         int edge_idx = vertex.neiEdge(vertex.neiBegin());

         // is it is double or triple bond => not hydrogen
         if (query.getBondOrder(edge_idx) > 1)
            continue;

         // ring bond? 
         if (query.getBondTopology(edge_idx) == TOPOLOGY_RING)
            continue;

         // can be something other than hydrogen?
         if (query.getAtomNumber(i) == -1)
            return true;
         if (is_fragment && i == query.vertexBegin())
            // If first atom in a fragment is hydrogen then hydrogens should 
            // be unfolded because of the matching logic: when fragment will be
            // matched this first hydrogen should match some atom. 
            // If hydrogens is not be unfolded in this case then 
            // [$([#1][N])]C will not match NC.
            return true;

         // If we need to find all embeddings then query hydrogens cannot be ignored:
         // For example, if we are searching number of matcher for N-[#1] in N then 
         // it should 3 instead of 1
         if (disable_folding_query_h)
            return true;

         // Check if hydrogen forms a cis-trans bond or stereocenter
         int nei_vertex_idx = vertex.neiVertex(vertex.neiBegin());
         if (query.stereocenters.exists(nei_vertex_idx))
            return true;

         // For example for this query hydrogens should be unfolded: [H]\\C=C/C
         const Vertex &nei_vertex = query.getVertex(nei_vertex_idx);
         for (int nei = nei_vertex.neiBegin(); nei != nei_vertex.neiEnd(); nei = nei_vertex.neiNext(nei))
         {
            int edge = nei_vertex.neiEdge(nei);
            if (query.cis_trans.getParity(edge) != 0)
               return true;
         }
      }

      if (_shouldUnfoldTargetHydrogens_A(&query.getAtom(i), is_fragment, disable_folding_query_h))
         return true;
   }

   MoleculeRGroups &rgroups = query.rgroups;

   int n_rgroups = rgroups.getRGroupCount();
   for (i = 1; i <= n_rgroups; i++)
   {
      PtrPool<BaseMolecule> &frags = rgroups.getRGroup(i).fragments;
      for (j = frags.begin(); j != frags.end(); j = frags.next(j))
         if (_shouldUnfoldTargetHydrogens(frags[j]->asQueryMolecule(), is_fragment, disable_folding_query_h))
            return true;
   }

   return false;
}