3961. Fenbenicillin

Nomenclature

CAS number: 1926-48-3
(2S,5R,6R)-3,3-Dimethyl-7-oxo-6-[(phenoxyphenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid; 3,3-dimethyl-7-oxo-6-(2-phenoxy-2-phenylacetamido)-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate; α-phenoxybenzylpenicillin; 6-(α-phenoxyphenylacetamido)penicillanic acid; 6-(α-phenoxy-α-phenylacetamido)penicillanate; phenbenicillin.
C22H22N2O5S; mol wt 426.49.
C 61.96%, H 5.20%, N 6.57%, O 18.76%, S 7.52%.

Description and references

Semi-synthetic antibiotic related to penicillin. Prepn: GB 877120 (1961 to Beecham). Bacteriological and pharmacological properties: Rollo, Burley, Br. Med. J. I, 76 (1962).

Chemical structure

Derivative

Potassium salt.

Nomenclature

CAS number: 1177-30-6
Penspek (formerly).
C22H21KN2O5S; mol wt 464.58.
C 56.88%, H 4.56%, K 8.42%, N 6.03%, O 17.22%, S 6.90%.

Properties

Powder, mp 88-95°, dec 120-125°. Readily sol in water. LD50 in mice (mg/kg): 225 i.v.; 520 i.p.; 3000 orally (Rollo, Burley).

Therapeutic Category

Antibacterial.

Keywords

Antibacterial (Antibiotics); β-Lactams; Penicillins