Monobactams and

First (3-lactamase inhibitor combination. First monobactam and a synthetic product. First carbapenem. 

Metallo-enzymes belonging to group 3 naturally show a very broad substrate spectrum including all (3-lactams excqrt monobactams and are not inhibited by clavulanic acid, but by complexing agents, like EDTA. This can only be exploited for diagnostic purposes. 

P-Lactamases are enzymes that hydrolyze the P-lactam ring of P-lactamantibiotics (penicillins, cephalosporins, monobactams and carbapenems). They are the most common cause of P-lactam resistance. Most enzymes use a serine residue in the active site that attacks the P-lactam-amid carbonyl group. The covalently formed acylester is then hydrolyzed to reactivate the P-lacta-mase and liberates the inactivated antibiotic. Metallo P-lactamases use Zn(II) bound water for hydrolysis of the P-lactam bond. P-Lactamases constitute a heterogeneous group of enzymes with differences in molecular structures, in substrate preferences and in the genetic localizations of the encoding gene (Table 1). 

The penicillins and cephalosporins share their mechanism of action, pharmacological effects, clinical effects and also immunologic characteristics. They are called beta-lactam drugs because of their unique lactam ring. This ring is present in the penicillins, the cephalosporins, monobactams and carbapenems. The biological activity depends on the presence and... 

Beta lactam antibiotics having a (3-lactam ring, which includes penicillin, in which a thiazolidine ring is attached to a betalactam ring that carries a secondary amino group. Other similar compounds are cephalosporins, monobactams and carbapenems. 

S. Hanessian, C. Couture, and H. Wyss, Design and reactivity of organic functional groups. Utility of imidazolylsulfonates in the synthesis of monobactams and 3-amino nocardicinic acid, Can. J. Chem. (55 3613 (1985). 

Singh GS (2004) In [3-Lactams in the new millenium. Part. I monobactams and carbape-nems. Mini Rev Med Chem 4 69... 

Other /3-lactam derivatives (e.g., monobactams and carbapen-ems) have been studied for potential cross-reactivity with peniciUms. In vitro and in vivo studies have demonstrated that aztreonam only weakly cross-reacts with penicillin and that it may be administered safely to most patients who are peniciUin-allergic. In contrast, there is considerable cross-reactivity between imipenem (a carbapenem) and penicillin. Therefore, imipenem (and other carbapenems) should not be administered to patients who have positive penicillin skin tests. 

First monobactam and a synthetic product. First carbapenem. 

The f)-lactam class (penicillins, cephalosporins, monobactams, and carbapenems), exert their activity via inhibition of membrane-bound enzymes, resulting in interference with bacterial cell wall peptidoglycan synthesis. These enzymes are termed penicillin-binding proteins (PBPs) because of their ability to covalently bind f)-lactam antibiotics. ... 

So named because of the presence of a four-membered f)-lactam ring in the molecules, the p-lactam antibiotics comprise four main classes of drugs that possess antibacterial action, viz., penams (penicillins), cephems (cephalosporins), monobactams, and carbapenans. The p-lactam ring is fused to a thiazolidine ring in penams, a dihydrothiazine ring in cephems, and a dihydro-... 

The question of tolerability of penicillins, monobactams, and carbapenems in patients with IgE hypersensitivity to cephalosporins was recently assessed in 98 subjects by serum IgE antibody assays, challenge tests, and skin testing with penicillin reagents, aztreonam, imipenem-cilastatin, and meropenem. Approximately 25 % of cephalosporin-allergic subjects were positive to penicillins, while 3.1,2, and 1 % showed positive results to aztreonam, imipenem, and meropenem, respectively. A reaction to a cephalosporin with a similar or identical side chain to penicillin was a sigifificant predictor of cross-reactivity. For skin testing, the following concentrations were used ampicillin and amoxicillin 1 and 20 mg/ml cephalosporins 2 mg/ml aztreonam 2 mg/ml imipenem-cilastatin 0.5 mg/ml and meropenem 1 mg/ml. 

The p-lactam antibiotics comprise four main classes of drugs that possess antibacterial action, viz., penams (penicillins), cephems (cephalosporins), monobactams, and carbapenems. 

Romano A, Gaeta F, Valluzzi RL, et al. IgE-mediated hypersensitivity to cephalosporins cross-reactivity and tolerability of penicillins, monobactams, and car-bapenems. 1 Allergy Clin Immunol. 2010 126 994-9. 

Chemically modified monobactams and their nonantimicrobial properties... 

The j6-lactam (azetidin-2-one) skeleton is the core stmcture of commonly used antibiotics including penicillins, cephalosporins, carbapenems, and monobactams, and of... 

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