def PhyChem(smiles):
""" Calculating the 19D physicochemical descriptors for each molecules,
the value has been normalized with Gaussian distribution.
Arguments:
smiles (list): list of SMILES strings.
Returns:
props (ndarray): m X 19 matrix as normalized PhysChem descriptors.
m is the No. of samples
"""
props = []
for smile in smiles:
mol = Chem.MolFromSmiles(smile)
try:
MW = desc.MolWt(mol)
LOGP = Crippen.MolLogP(mol)
HBA = Lipinski.NumHAcceptors(mol)
HBD = Lipinski.NumHDonors(mol)
rotable = Lipinski.NumRotatableBonds(mol)
amide = AllChem.CalcNumAmideBonds(mol)
bridge = AllChem.CalcNumBridgeheadAtoms(mol)
heteroA = Lipinski.NumHeteroatoms(mol)
heavy = Lipinski.HeavyAtomCount(mol)
spiro = AllChem.CalcNumSpiroAtoms(mol)
FCSP3 = AllChem.CalcFractionCSP3(mol)
ring = Lipinski.RingCount(mol)
Aliphatic = AllChem.CalcNumAliphaticRings(mol)
aromatic = AllChem.CalcNumAromaticRings(mol)
saturated = AllChem.CalcNumSaturatedRings(mol)
heteroR = AllChem.CalcNumHeterocycles(mol)
TPSA = MolSurf.TPSA(mol)
valence = desc.NumValenceElectrons(mol)
mr = Crippen.MolMR(mol)
# charge = AllChem.ComputeGasteigerCharges(mol)
prop = [
MW, LOGP, HBA, HBD, rotable, amide, bridge, heteroA, heavy,
spiro, FCSP3, ring, Aliphatic, aromatic, saturated, heteroR,
TPSA, valence, mr
]
except Exception:
print(smile)
prop = [0] * 19
props.append(prop)
props = np.array(props)
props = Scaler().fit_transform(props)
return props
def SA_score(smile):
mol = Chem.MolFromSmiles(smile)
# fragment score
fp = Chem.GetMorganFingerprint(mol, 2)
fps = fp.GetNonzeroElements()
score1 = 0.
nf = 0
# for bitId, v in fps.items():
for bitId, v in fps.items():
nf += v
sfp = bitId
score1 += SA_model.get(sfp, -4) * v
score1 /= nf
# features score
nAtoms = mol.GetNumAtoms()
nChiralCenters = len(Chem.FindMolChiralCenters(mol,
includeUnassigned=True))
ri = mol.GetRingInfo()
nSpiro = Chem.CalcNumSpiroAtoms(mol)
nBridgeheads = Chem.CalcNumBridgeheadAtoms(mol)
nMacrocycles = 0
for x in ri.AtomRings():
if len(x) > 8:
nMacrocycles += 1
sizePenalty = nAtoms**1.005 - nAtoms
stereoPenalty = math.log10(nChiralCenters + 1)
spiroPenalty = math.log10(nSpiro + 1)
bridgePenalty = math.log10(nBridgeheads + 1)
macrocyclePenalty = 0.
# ---------------------------------------
# This differs from the paper, which defines:
# macrocyclePenalty = math.log10(nMacrocycles+1)
# This form generates better results when 2 or more macrocycles are present
if nMacrocycles > 0:
macrocyclePenalty = math.log10(2)
score2 = 0. - sizePenalty - stereoPenalty - \
spiroPenalty - bridgePenalty - macrocyclePenalty
# correction for the fingerprint density
# not in the original publication, added in version 1.1
# to make highly symmetrical molecules easier to synthetise
score3 = 0.
if nAtoms > len(fps):
score3 = math.log(float(nAtoms) / len(fps)) * .5
sascore = score1 + score2 + score3
# need to transform "raw" value into scale between 1 and 10
min = -4.0
max = 2.5
sascore = 11. - (sascore - min + 1) / (max - min) * 9.
# smooth the 10-end
if sascore > 8.:
sascore = 8. + math.log(sascore + 1. - 9.)
if sascore > 10.:
sascore = 10.0
elif sascore < 1.:
sascore = 1.0
val = remap(sascore, 5, 1.5)
val = np.clip(val, 0.0, 1.0)
return val
def NumBridgeheadsAndSpiro(mol, ri=None):
nSpiro = AllChem.CalcNumSpiroAtoms(mol)
nBridgehead = AllChem.CalcNumBridgeheadAtoms(mol)
return nBridgehead, nSpiro
