Title: Cefmetazole
CAS Registry Number: 56796-20-4
CAS Name: (6R,7S)-7-[[[(Cyanomethyl)thio]acetyl]amino]-7-methoxy-3-[[(1-methyl-1H-tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
Manufacturers' Codes: CS-1170; SKF-83088
Molecular Formula: C15H17N7O5S3
Molecular Weight: 471.53
Percent Composition: C 38.21%, H 3.63%, N 20.79%, O 16.97%, S 20.40%
Literature References: Semi-synthetic antibiotic derived from cephamycin C, q.v. Prepn: H. Nakao et al., DE 2455884 (1975 to Sankyo), C.A. 83, 97330g (1975); eidem, J. Antibiot. 29, 554 (1976). See also: J. E. Dolfini, US 3920639 (1975 to Squibb). In vitro study: J. V. Uri et al., ibid. 31, 82 (1978). Immunological study: M. Iwata, T. Matuhasi, Jpn. J. Exp. Med. 48, 401 (1978). Absorption, distribution, excretion, metabolism in various species: H. Shindo et al., Chemotherapy (Tokyo) 27, Suppl. 1, 64 (1979). Pharmacology: S. Kobayashi et al., ibid. 26, Suppl. 5, 115 (1978). Toxicological studies: H. Masuda et al., Sankyo Kenkyusho Nempo 30, 112 (1978), C.A. 90, 180268h (1979). Comparative clinical study: M. Nishida et al., J. Antibiot. 32, 1319 (1979).
Derivative Type: Sodium salt
CAS Registry Number: 56796-39-5
Trademarks: Cefmetazon (Sankyo); Metafar (Lafare); Zefazone (Pharmacia & Upjohn)
Molecular Formula: C15H16N7NaO5S3
Molecular Weight: 493.52
Percent Composition: C 36.51%, H 3.27%, N 19.87%, Na 4.66%, O 16.21%, S 19.49%
Properties: White solid. Very sol in water, methanol, sol in acetone. Practically insol in chloroform. LD50 i.v. in rats: >5000 mg/kg (Masuda).
Toxicity data: LD50 i.v. in rats: >5000 mg/kg (Masuda)
Therap-Cat: Antibacterial.
Keywords: Antibacterial (Antibiotics); ?Lactams; Cephamycins.
Cefminox Cefodizime Cefonicid Cefoperazone Ceforanide

Systematic (IUPAC) name
(6R,7S)-7-(2-(cyanomethylthio)acetamido)-7-methoxy-3-((1-methyl-1H-tetrazol-5-ylthio)methyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
Clinical data
AHFS/Drugs.com International Drug Names
MedlinePlus a601206
Legal status  ?
CAS number 56796-20-4 YesY
ATC code J01DC09
PubChem CID 42008
DrugBank DB00274
ChemSpider 38311 YesY
KEGG D00910 YesY
Chemical data
Formula C15H17N7O5S3 
Mol. mass 471.538 g/mol
 N (what is this?)  (verify)

Cefmetazole is a cephalosporin antibiotic, usually grouped with the second-generation cephalosporins.