133655-82-0

Upstream product

• 52681-36-4 diphenylmethyl (6R,7R)-7-isocyano-3-methylceph-3-em-4-carboxylate 
• 132261-21-3 C₂₃H₂₀N₂O₃S₂ 

Downstream Products

• 132261-12-2 diphenylmethyl 7-(imidazol-2-ylamino)-7-methoxy-3-methylceph-3-em-4-carboxylate 
• 132261-11-1 (6R,7S)-7-(4,5-Dihydro-1H-imidazol-2-ylamino)-3-methyl-7-methylsulfanyl-8-oxo-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester 

Relevant academic research and scientific papers

Synthesis and structure-activity relationship of new cephalosporins with amino heterocycles at C-7. Dependence of the antibacterial spectrum and β-lactamase stability on the pK(a) of the C-7 heterocycle

Cephalosporins with new aminobenzimidazole and aminoimidazoline heterocycles at C-7 have been synthesized starting with versatile C-7 isocyanide dihalide synthons. The aminobenzimidazoles have a broad spectrum of antibacterial activity, including Gram-positive and Gram-negative organisms, but possess limited β-lactamase stability. In contrast, the aminoimidazolines have a narrow spectrum of antibacterial activity, limited to Gram-negative strains only, but possess outstanding β-lactamase stability. Structure-activity relationships are discussed in terms of their dependence on the pK(a) of the C-7 amino heterocycle, basic C-7 residues giving cephalosporins with exceptional β-lactamase stability.