Cephalothin 7-methyl

The polarographic reductions of cephaloridine, cephalothin, and cephalosporin C each yield one wave that is both pH and concentration dependent [126]. The reduction of these compounds and a related derivative, 3-(5-methyl-1,3,4-thiadiazol-2-ylthiomethyl)-7-[2-(3-sydnone)acetamido]-3-cephem-4-carboxylic acid-sodium salt [I], have been described [127]. The reduction of I yields two waves. The first is believed to be the two-electron reductive elimination of the... 

Prochlorperazine Edisylate Prochlorperazine edisylate is not compatible with sodium chloride solutions containing methyl hydroxybenzoate and propyl hydroxy-benzoate as preservatives, but is compatible with solutions containing benzyl alcohol. Prochlorperazine edisylate salts are incompatible with a number of drugs such as aminophylline, amphotericin, ampicillin sodium, some barbiturates, ben-zylpenicillin salts, calcium gluconate, cefmetazole sodium, cephalothin sodium, chloramphenicol sodium succinate, chlorothiazide sodium, chloramphenicol, morphine sulfate containing phenol, magnesium trisilicate mixture, sodium succinate, chlorothiazide sodium, dimenhydrinate, heparin sodium, hydrocortisone sodium succinate, midazolam hydrochloride, and some sulfonamides.166... 

More interesting, the presence of the thiophene ring in position 7 of the cephem nucleus (Figure 2) has been associated with nephrotoxic effects in the case of cephaloridine and cephalothin and to a lesser extent in the case of the cephamycin cefoxitin [26, 66]. When compared to cephalothin, small alterations of the cefoxitin molecule in positions 3 and 7 of the cephem nucleus, such as replacement of the methyl group with... 

NMR spectroscopy has been the most useful tool in cephalosporin C chemistry. In cephalosporins the carbons are unsaturated or highly substituted with heteroatoms, and the protons are usually widely separated in chemical shift and have simple coupling patterns. Recently, solvent induced chemical shifts, nuclear Overhauser effects, and the anisotropy of the sulfoxide bond have been utilized in chemical studies of cephalosporin C derivatives. Analytical information may be derived from NMR spectra of cephalothin by observing the contribution of the 0-lactam protons, thiophene protons, methylene groups, and methyl protons (from acetate). 

Chemists from Takeda Chemical Industries (Japan) were the first to publish a practical conversion of cephalosporanic acids to 3-methyle-necephams (Ochiai et al., 1972a). They treated sodium cephalothin (6)... 

In a continuing effort to utilize polarographic reductions as an analytical tool in cephalosporin chemistry, scientists at the Lilly Research Laboratories made a detailed electrochemical study of cephalothin (Hall, 1973 Hall et al., 1977). The reductive cleavage of the acetoxy group at C-10 in compound 56 was found to produce 7-(thiophene-2-acetamido)-3-methylenecepham-4-carboxylic acid (57) as the predominant product along with varying amounts of its stereoisomer at C-4 (58) and 7-(thio-phene-2-acetamido)-3-methyl-3-cephem-4-carboxylic acid (59), depending upon pH and electrode potential. 

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