163648-72-4Relevant academic research and scientific papers
De-esterification process
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, (2008/06/13)
An efficient process for de-esterification has been provided for by application of special tetrahalogenides. By applying this process a new compound, viz. cefesone, and especially the E-isomer thereof, has been prepared.
Titanium tetrachloride promoted hydrolysis of cephalosporin tert-butyl esters
Valencic, Marjan,Van Der Does, Thom,De Vroom, Erik
, p. 1625 - 1628 (2007/10/03)
Titanium tetrachloride was used as a mild and effective deprotective reagent for the hydrolysis of cephalosporin tert-butyl esters. Yields up to 91% were obtained.
Synthesis of the β-lactamase indicators Cefesone and Nitrocefin
Barendse, Nico C. M. E.,Van Der Klein, Pieter A. M.,Verweij, Jan,Witkamp, Henk A.,Van Zoest, Wim J.,De Vroom, Erik
, p. 145 - 147 (2007/10/03)
The synthesis of the β-lactamase indicators Cefesone [(6R,7R)-3-(2,4- dinitrostyryl)-7-(phenylacetamido)ceph-3-em-4-carboxylic acid] and Nitrocefin [(6R,7R)-3-(2,4-dinitrostyryl)-7-(2-thienylacetamido)ceph-3-em-4-carboxylic acid] from tert-butyl (1S,6R,7R)-3-bromomethyl-1-oxo-7-(phenylacetamido)ceph- 3-em-4-carboxylate is reported. Phosphonylation of the latter compound with triphenylphosphine gave the corresponding phosphonium derivative in 93% yield. Reduction followed by Wittig coupling with 2,4-dinitrobenzaldehyde gave a 1:12 mixture of E- and Z-isomers in 83% yield. The tert-butyl protecting group was removed with titanium tetrachloride to give Cefesone as the pure crystalline E-isomer in 63% yield. De-acylation was achieved by enzymatic hydrolysis in 77% yield. Finally the 2-thienylacetyl side chain was introduced to give crystalline Nitrocefin in 67% yield.
