Described herein are crystalline forms of a compound of formula (III.sup.−), including toluene solvates off A TD-CLE, as well as processes for the preparation thereof and use thereof in the preparation of cephalosporin compounds such as ceftolozane. Provided herein is a crystalline form of a compound of formula (III.sup.−): wherein X is CI, Br, or I; and R1 and R2 are each independently an oxygen protecting group; processes for making the crystalline form, and use of said form in the synthesis of antibacterial cephalosporins such as ceftolozane.

Described herein are crystalline forms of a compound of formula (III.sup.−), including toluene solvates off A TD-CLE, as well as processes for the preparation thereof and use thereof in the preparation of cephalosporin compounds such as ceftolozane. Provided herein is a crystalline form of a compound of formula (III.sup.−): wherein X is CI, Br, or I; and R1 and R2 are each independently an oxygen protecting group; processes for making the crystalline form, and use of said form in the synthesis of antibacterial cephalosporins such as ceftolozane.

Broad spectrum beta-lactamase inhibitors. Certain inhibitors also exhibit potent antibiotic activity in addition to beta-lactamase inhibition. Compounds of the invention are designed such that on cleavage of the beta-lactam ring reactive moieties are generated which can inactivate beta-lactamase. Also provided are methods of making beta-lactamase inhibitors and beta-lactam antibiotics exhibiting such inhibition. Additionally provided are pharmaceutical compositions for treatment or prevention of bacterial infections and methods of treatment of such infections.

Broad spectrum beta-lactamase inhibitors. Certain inhibitors also exhibit potent antibiotic activity in addition to beta-lactamase inhibition. Compounds of the invention are designed such that on cleavage of the beta-lactam ring reactive moieties are generated which can inactivate beta-lactamase. Also provided are methods of making beta-lactamase inhibitors and beta-lactam antibiotics exhibiting such inhibition. Additionally provided are pharmaceutical compositions for treatment or prevention of bacterial infections and methods of treatment of such infections.

Broad spectrum beta-lactamase inhibitors. Certain inhibitors also exhibit potent antibiotic activity in addition to beta-lactamase inhibition. Compounds of the invention are designed such that on cleavage of the beta-lactam ring reactive moieties are generated which can inactivate beta-lactamase. Also provided are methods of making beta-lactamase inhibitors and beta-lactam antibiotics exhibiting such inhibition. Additionally provided are pharmaceutical compositions for treatment or prevention of bacterial infections and methods of treatment of such infections.

Broad spectrum beta-lactamase inhibitors. Certain inhibitors also exhibit potent antibiotic activity in addition to beta-lactamase inhibition. Compounds of the invention are designed such that on cleavage of the beta-lactam ring reactive moieties are generated which can inactivate beta-lactamase. Also provided are methods of making beta-lactamase inhibitors and beta-lactam antibiotics exhibiting such inhibition. Additionally provided are pharmaceutical compositions for treatment or prevention of bacterial infections and methods of treatment of such infections.

Described herein are crystalline forms of a compound of formula (III), including toluene solvates of TATD-CLE, as well as processes for the preparation thereof and use thereof in the preparation of cephalosporin compounds such as ceftolozane.

Described herein are crystalline forms of a compound of formula (III), including toluene solvates of TATD-CLE, as well as processes for the preparation thereof and use thereof in the preparation of cephalosporin compounds such as ceftolozane.

A refining method of a midbody of latamoxef sodium includes: dissolving 7-amino-7-methoxy-3-(5-tetrazolyl)thiomethyl-1-oxa-3-cephem-4-carboxylic acid in dichloromethane, and then dividing into a dichloromethane layer and a water layer; extracting the dichloromethane layer, adding a NaHCO.sub.3 solution to stir, and remaining an organic layer after stratification; stirring, crystallizing and filtering the organic layer in turn, to obtain a filtrate, preparing a second powder by stirring the filtrate under conditions of a catalyst and a normal temperature; preparing a first powder by extracting the water layer, dropping the hydrochloric acid to adjust a pH value thereof, performing crystal cultivation and suction filtration after performing cooling, and then performing vacuum drying; combining the first powder and the second powder to prepare the midbody of latamoxef sodium: 73-amino-7-methoxy-3-(5-tetrazolyl)thiomethyl-1-oxa-3-cephem-4-carboxylic acid, which has a yield of 95.6-96.8% and a purity of 99.2-99.5%.

Described herein are crystalline forms of a compound of formula (III), including toluene solvates of TATD-CLE, as well as processes for the preparation thereof and use thereof in the preparation of cephalosporin compounds such as ceftolozane.