This invention provides novel β-lactamase inhibitors of the aryl- and heteroarylsulfonamidomethylphosphonate monoester class having nitrogen-based cations or quarternary ammonium groups. The compounds inhibit three classes of β-lactamases and synergize the antibacterial effects of β-lactam antibiotics (e.g., imipenem and ceftazidime) against those micro-organisms normally resistant to the β-lactam antibiotics as a result of the presence of the β-lactamases. Formula (I) or pharmaceutically acceptable salt thereof.
and also allows the use of the synthetic approach for more complex compounds. Two convenientprocedures for the synthesis of thia- and azacrown ether containing 4-nitro-1,8-naphthalimides have been developed. The first procedure is based on the amination of 1,8-naphthalic anhydride with crown-containing anilines. The second procedure includes the macrocyclization reaction of N-[1,2-bis(2-haloethox