Athanor by arbastro
download
Library

Penicillin G

Athanor · official

C16H18N2O4S · 334.4 g/mol

IUPAC name: 3,3-dimethyl-7-oxo-6-[(2-phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid

Also called benzylpenicillin, Pen G, beta-lactam

DrugsNatural products
Open in Athanor
The structure of Penicillin G
Drawn from its SMILES with RDKit

Names and identifiers

IUPAC name
3,3-dimethyl-7-oxo-6-[(2-phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
Synonyms
benzylpenicillin, Pen G, beta-lactam
+ 37 more

CHEBI:17334, penicillins, Penicillin Antibiotics, Antibiotics, Penicillin, RefChem:126139, DTXSID501017130, 215-794-6, Penicillin, Cillin, Benzopenicillin, (5S)-3,3-dimethyl-7-oxo-6-[(2-phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, Benzylpenicillin G, Free benzylpenicillin, (Phenylmethyl)penicillin, 3,3-Dimethyl-7-oxo-6-[(phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, Penicillinic acid, benzyl-, (Phenylmethyl)penicillinic acid, Benzyl-6-aminopenicillinic acid, 3,3-dimethyl-7-oxo-6-((phenylacetyl)amino)-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, Penicilline G sodium salt, Epitope ID:115007, Oprea1_713794, Oprea1_861345, 3,3-dimethyl-7-oxo-6-[(2-phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, CHEMBL300052, SCHEMBL2109546, DTXSID20274362, NSC11964, STL453455, AKOS030242685, SB74416, 3,3-Dimethyl-7-oxo-6-(2-phenylacetamido)-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid, NCI60_000703, NS00001514, WLN: T45 ANV ESTJ CMV1R& F F GVQ, 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,3-dimethyl-7-oxo-6-(2-phenylacetamido)-, 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,3-dimethyl-7-oxo-6-[(phenylacetyl)amino]- [2S-(2.alpha.,5.alpha.,6.beta.)]-

Molecular formula
C16H18N2O4S
Empirical formula
C16H18N2O4S
Molecular weight
334.4 g/mol
Exact mass
334.09873
CAS number
61-33-6
PubChem CID
2349
Canonical SMILES
CC1(C(N2C(S1)C(C2=O)NC(=O)CC3=CC=CC=C3)C(=O)O)C
Isomeric SMILES
CC1(C(N2C(S1)C(C2=O)NC(=O)CC3=CC=CC=C3)C(=O)O)C
InChI
InChI=1S/C16H18N2O4S/c1-16(2)12(15(21)22)18-13(20)11(14(18)23-16)17-10(19)8-9-6-4-3-5-7-9/h3-7,11-12,14H,8H2,1-2H3,(H,17,19)(H,21,22)
InChIKey
JGSARLDLIJGVTE-UHFFFAOYSA-N
Molfile

Names, InChI and the identifiers from PubChem, retrieved 2026-10-14.

Calculated

Heavy atoms
23
Rings
3
Aromatic rings
1
Fraction sp³ carbons (Fsp3)
0.44
H-bond donors
2
H-bond acceptors
4 computed here · PubChem 5
Rotatable bonds
4
TPSA (Ų)
86.7 computed here · PubChem 112
Formal charge
0
XLogP3
1.8 PubChem
Complexity
530 PubChem
Stereocenters
0 defined, 3 undefinedCIP: C5: undefined · C6: undefined · C20: undefined
Double-bond geometry
None specified
Point group
C1 of one 3D conformer with its hydrogens, by Athanor’s engine (as in the app)

Elemental analysis

  • C57.47%
  • H5.43%
  • N8.38%
  • O19.14%
  • S9.59%

Isotope pattern

100%334.09919%335.1027.1%336.0981.1%337.100338.100

Each peak is a nominal mass with its abundance-weighted exact mass, as a percentage of the tallest, from IUPAC natural isotope abundances.

Computed from the structure with RDKit 2026.09 when this page was built, beside PubChem's own computed values from its record; where the two differ, both are shown.

Predicted

log P
0.86 Crippen (Wildman and Crippen 1999)
log S (water solubility)
-2.38 ESOL (Delaney 2004), log mol/L
Synthetic accessibility
3.2 SA score, 1 easy to 10 hard (Ertl and Schuffenhauer 2009)

Drug-likeness: Lipinski’s rule of five

  • Molecular weight ≤ 500: 334.4
  • log P ≤ 5 (Crippen): 0.86
  • H-bond donors ≤ 5: 2
  • H-bond acceptors ≤ 10: 4

Passes all four rules.

¹³C NMR shifts, predicted

Predictions, not measurements; each names its method. A measured log P, where a source reports one, is under Physical properties.

Safety

No GHS hazard classification was found in the sources.

Safety data sheets on the supplier’s page: MolCore, Angene Chemical, Alfa Chemistry.

Always read the supplier’s safety data sheet before working with it.

Spectra

Experimental spectra held by these sources; each link opens the source's own record.

Literature

Reading PubChem, OpenAlex and GSRS…

Bioactivity

Reading ChEMBL…

References

  1. [1]SpectraBase · Linked only · via PubChem · retrieved 2026-10-14
  2. ·Calculated values: computed by Athanor with RDKit 2026.09 from the structure.
  3. ·Literature on PubChem

Data last updated 2026-10-14.