217803-89-9 Usage
Uses
Cefotaxime Proxetil (Cefpodoxime Proxetil EP Impurity E) is an impurity of Cefotaxime (C242950), which is a broad spectrum third generation cephalosporin antibiotic. The name Cefotaxime applies to the isomer having a syn-methoxy imino group.
Check Digit Verification of cas no
The CAS Registry Mumber 217803-89-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 2,1,7,8,0 and 3 respectively; the second part has 2 digits, 8 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 217803-89:
(8*2)+(7*1)+(6*7)+(5*8)+(4*0)+(3*3)+(2*8)+(1*9)=139
139 % 10 = 9
So 217803-89-9 is a valid CAS Registry Number.
217803-89-9Relevant articles and documents
Preparation of Ceph-3-em esters unaccompanied by Δ3 to Δ2 isomerization of the cephalosporin derivatives
Lee, Hong Woo,Kang, Tae Won,Kim, Eung Nam,Cha, Kyung Hoi,Shin, Jaewook,Cho, Dong Ock,Choi, Nam Hee,Kim, Jung Woo,Hong, Chung Il
, p. 1873 - 1887 (1999)
A synthesis of cephalosporin derivatives by reacting cephalosporin free carboxylic acid with alkyl halide in the presence of cesium carbonate and potassium carbonate is disclosed. Δ3 to Δ2 isomerization, a side reaction commonly reported in preparation of cephalosporin derivatives, was successfully eliminated. The desired Δ3 was obtained as a sloe product in the reaction.
