Title: Ampicillin
CAS Registry Number: 69-53-4
CAS Name: (2S,5R,6R)-6-[[(2R)-Aminophenylacetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
Additional Names: 6-[D(-)-a-aminophenylacetamido]penicillanic acid; D(-)-a-aminobenzylpenicillin
Manufacturers' Codes: AY-6108; BRL-1341; P-50
Trademarks: Albipen (Intervet); Amfipen (Yamanouchi); Ampitab (Voquinol); Amplital (Pharmacia); Omnipen (Wyeth); Pénicline (Sanofi-Aventis)
Molecular Formula: C16H19N3O4S
Molecular Weight: 349.40
Percent Composition: C 55.00%, H 5.48%, N 12.03%, O 18.32%, S 9.18%
Literature References: Orally active, semi-synthetic antibiotic; structurally related to penicillin. Prepn: Doyle et al., US 2985648 (1961); eidem, GB 902703 (1962 to Beecham); Doyle et al., J. Chem. Soc. 1962, 1440. Prepn of the trihydrate: D. A. Johnson, G. A. Hardcastle, US 3157640 (1964 to Bristol-Myers); of the anhydrous crystalline form: N. H. Grant, H. E. Alburn, US 3144445 (1964 to Am. Home Prods.). Alternate syntheses: Dane, Dockner, Ber. 98, 789 (1965); F. Kajfez et al., J. Heterocycl. Chem. 13, 561 (1976). LC determn: M. Margosis, J. Assoc. Off. Anal. Chem. 70, 206 (1987). Series of articles on pharmacology and antibacterial activity: Br. Med. J. 2, 193-206 (1961). Comprehensive description: E. Ivashkiv, Anal. Profiles Drug Subs. 2, 1-61 (1973). Review of pharmacology and clinical efficacy in combination with sulbactam, q.v.: D. M. Campoli-Richards, R. N. Brogden, Drugs 33, 577-609 (1987).
Properties: Crystals, dec 199-202°. [a]D23 +287.9° (c = 1 in water). Sparingly sol in water.
Optical Rotation: [a]D23 +287.9° (c = 1 in water)
Derivative Type: Monohydrate
Properties: Crystals from water, dec 202°. [a]D21 +281° (water). Sparingly sol in water at room temp.
Optical Rotation: [a]D21 +281° (water)
Derivative Type: Sesquihydrate
Properties: Dec 199-202°. [a]D20 +283.1° (water).
Optical Rotation: [a]D20 +283.1° (water)
Derivative Type: Trihydrate
CAS Registry Number: 7177-48-2
Trademarks: Amblosin (Hoechst); Amipenix (Toyo Jozo); Ampilar (Sandoz); Cymbi (Dolorgiet); Doktacillin (AstraZeneca); Penbritin (GSK); Polycillin (BMS); Principen (BMS); Rosampline (Tedis); Totapen (BMS); Vidopen (APS)
Derivative Type: Sodium salt
CAS Registry Number: 69-52-3
Trademarks: Ampicin (BMS); Binotal (Grenthal); Cilleral (BMS); Penbristol (BMS); Pentrex (BMS); Pentrexyl (BMS); Polycillin-N (BMS); Synpenin (Sankyo); Totacillin N (GSK); Viccillin (Meiji)
Molecular Formula: C16H18NaN3O4S
Molecular Weight: 371.39
Percent Composition: C 51.74%, H 4.89%, Na 6.19%, N 11.31%, O 17.23%, S 8.63%
Derivative Type: L(+)-Form
Properties: Crystals, dec at about 205°. [a]D20 +209° (c = 0.2 in water). Less active as an antibiotic than D(-)-form.
Optical Rotation: [a]D20 +209° (c = 0.2 in water)
Therap-Cat: Antibacterial.
Therap-Cat-Vet: Antibacterial.
Keywords: Antibacterial (Antibiotics); ?Lactams; Penicillins.
Ampiroxicam Amprenavir Amprolium Amprotropine Phosphate Ampyrone

Ampicillin Structural Formulae V.1.svg
Ampicillin 3d structure pdb.gif
Systematic (IUPAC) name
carboxylic acid
Clinical data
Trade names Principen
AHFS/ monograph
MedlinePlus a685002
Pregnancy cat. A (Au), B (U.S.)
Legal status  ?
Routes Oral, intravenous
Pharmacokinetic data
Bioavailability 40% (oral)
Protein binding 15 to 25%
Metabolism 12 to 50%
Half-life approx 1 hour
Excretion 75 to 85% renal
CAS number 69-53-4 YesY
ATC code J01CA01 S01AA19 QJ51CA01
PubChem CID 6249
DrugBank DB00415
ChemSpider 6013 YesY
UNII 7C782967RD YesY
KEGG D00204 YesY
ChEBI CHEBI:28971 YesY
Chemical data
Formula C16H19N3O4S 
Mol. mass 349.41 g·mol−1
 YesY (what is this?)  (verify)

Ampicillin is a beta-lactam antibiotic that is part of the aminopenicillin family and is roughly equivalent to its successor, amoxicillin in terms of spectrum and level of activity.[1] It can sometimes result in reactions that range in severity from a rash (in the case of patients who may unwittingly have mononucleosis) to potentially lethal allergic reactions such as anaphylaxis. However, as with other penicillin drugs, it is relatively nontoxic, and adverse effects of a serious nature are encountered only rarely.