Benethamine penicillin is a medium-long-acting insoluble penicillin salt. After a single injection, this salt acts and bacteriostatic level of penicillin is maintained in the blood for three to six days.

Olaquindox, a potent antibacterial agent, is used as an effective feed additive in the livestock industry. Olaquindox could potentially expose a human to the risk of biological hazards due to its genotoxicity and cytotoxicity. However, the potential mechanism of toxicity is still unknown. Recently was provided experiments to explore the molecular mechanism of p21 on olaquindox-induced mitochondrial apoptosis. It was shown, that olaquindox promoted the production of ROS, suppressed the protein expression p21 in a p53-independent way and phosphorylated p21. This experiment provided new insights into the molecular mechanism of olaquindox and shed light on the role of p21.

Difloxacin is an aryl fluoroquinolone derivative. The primary bacterial target of fluoroquinolones is the enzyme deoxyribonucleic acid gyrase. Difloxacin is very potent against a broad spectrum of bacteria including aerobic ana anaerobic gram-positive and gram-negative oragnisms. DICURAL® (difloxacin hydrochloride) TABLETS are indicated for the management of diseases in dogs associated with bacteria susceptible to difloxacin.

Sulfazamet is a sulfanilamide derivative that exhibits antibacterial activity against Streptococci sepsis

Doripenem is a synthetic carbapenem that has broad antibacterial potency against aerobic and anaerobic gram-positive and gram-negative bacteria. Doripenem is structurally related to beta-lactam antibiotics and shares the bactericidal mode of action of other β-lactam antibiotics by targeting penicillin-binding proteins (PBPs) to inhibit the biosynthesis of the bacterial cell wall. Doripenem is resistant to hydrolysis by most β-lactamases and is resistant to inactivation by renal dehydropeptidases. Doripenem has many similarities to the other carbapenems, as well as some important differences, such as greater potency against Pseudomonas aeruginosa. It was found to be similar to comparator agents. The most common adverse effects related to doripenem therapy were headache, nausea, diarrhea, rash, and phlebitis.

French pharmaceutical company Hoechst Marion Roussel (later Sanofi-Aventis) began phase II/III clinical trials of telithromycin (HMR-3647) in 1998. Telithromycin was approved by the European Commission in July 2001 and subsequently went on sale in October 2001. In the US, telithromycin received U.S. Food and Drug Administration (FDA) approval on April 1, 2004 Telithromycin is the first ketolide antibiotic to enter clinical use and is sold under the brand name of Ketek. After significant controversy regarding safety and research fraud, the US Food and Drug Administration sharply curtailed the approved uses of the drug in 2007. Telithromycin is a semi-synthetic erythromycin derivative. It is created by substituting a ketogroup for the cladinose sugar and adding a carbamate ring in the lactone ring. An alkyl-aryl moiety is attached to this carbamate ring. Furthermore, the carbon at position 6 has been methylated, as is the case in clarithromycin, to achieve better acid-stability. For the treatment of Pneumococcal infection, acute sinusitis, acute bacterial tonsillitis, acute bronchitis and bronchiolitis, lower respiratory tract infection and lobar (pneumococcal) pneumonia. KETEK tablets contain telithromycin, a semisynthetic antibacterial in the ketolide class for oral administration. Telithromycin blocks protein synthesis by binding to domains II and V of 23S rRNA of the 50S ribosomal subunit. By binding at domain II, telithromycin retains activity against gram-positive cocci (e.g., Streptococcus pneumoniae) in the presence of resistance mediated by methylases (erm genes) that alter the domain V binding site of telithromycin. Telithromycin may also inhibit the assembly of nascent ribosomal units.

Gemifloxacin is an oral broad-spectrum quinolone antibacterial agent used in the treatment of acute bacterial exacerbation of chronic bronchitis and mild-to-moderate pneumonia. Gemifloxacin mesylate is marketed under the brand name Factive, indicated for the treatment of bacterial infection caused by susceptible strains such as S. pneumoniae, H. influenzae, H. parainfluenzae, or M. catarrhalis, S. pneumoniae (including multi-drug resistant strains [MDRSP]), M. pneumoniae, C. pneumoniae, or K. pneumoniae. Gemifloxacin has in vitro activity against a wide range of Gram-negative and Grampositive microorganisms. Gemifloxacin is bactericidal with minimum bactericidal concentrations (MBCs) generally within one dilution of the minimum inhibitory concentrations (MICs). Gemifloxacin acts by inhibiting DNA synthesis through the inhibition of both DNA gyrase and topoisomerase IV (TOPO IV), which are essential for bacterial growth. Streptococcus pneumoniae showing mutations in both DNA gyrase and TOPO IV (double mutants) are resistant to most fluoroquinolones. Gemifloxacin has the ability to inhibit both enzyme systems at therapeutically relevant drug levels in S. pneumoniae (dual targeting), and has MIC values that are still in the susceptible range for some of these double mutants.

Cefditoren pivoxil is a semi-synthetic cephalosporin antibiotic for oral administration. It is a 3rd generation cephalosporin that is FDA approved for the treatment of acute bacterial exacerbation of chronic bronchitis, community acquired pneumonia, infection of skin and/or subcutaneous tissue, and pharyngitis/tonsillitis. Cefditoren is a cephalosporin with antibacterial activity against gram-positive and gram-negative pathogens. The bactericidal activity of cefditoren results from the inhibition of cell wall synthesis via affinity for penicillin-binding proteins (PBPs). Common adverse reactions include diarrhea, nausea and candida vaginitis. Co-administration of a single dose of an antacid which contained both magnesium (800 mg) and aluminum (900 mg) hydroxides or co-administration of a single dose of intravenously administered famotidine (20 mg) reduced the oral absorption of a single 400 mg dose of cefditoren pivoxil administered following a meal. Co-administration of probenecid with cefditoren pivoxil resulted in an increase in the plasma exposure of cefditoren.

Sparfloxacin is a synthetic fluoroquinolone broad-spectrum antimicrobial agent in the same class as ofloxacin and norfloxacin. Sparfloxacin has in vitro activity against a wide range of gram-negative and gram-positive microorganisms. Sparfloxacin exerts its antibacterial activity by inhibiting DNA gyrase, a bacterial topoisomerase. DNA gyrase is an essential enzyme which controls DNA topology and assists in DNA replication, repair, deactivation, and transcription. Quinolones differ in chemical structure and mode of action from (beta)-lactam antibiotics. Quinolones may, therefore, be active against bacteria resistant to (beta)-lactam antibiotics. Although cross-resistance has been observed between sparfloxacin and other fluoroquinolones, some microorganisms resistant to other fluoroquinolones may be susceptible to sparfloxacin. In vitro tests show that the combination of sparfloxacin and rifampin is antagonistic against Staphylococcus aureus. The bactericidal action of sparfloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination. Sparfloxacin is used for the treatment of adults with the following infections caused by susceptible strains microorganisms: community-acquired pneumonia (caused by Chlamydia pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, or Streptococcus pneumoniae) and acute bacterial exacerbations of chronic bronchitis (caused by Chlamydia pneumoniae, Enterobacter cloacae, Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis,Staphylococcus aureus, or Streptococcus pneumoniae). Sparfloxacin has trade names Spacin in Bangladesh, Zagam and Zagam Respipac. Zagam is no longer available in the United States.

Dirithromycin (Dynabac) is a macrolide glycopeptide antibiotic used to treat different types of bacterial infections, such as bronchitis, pneumonia, tonsillitis, skin infections. Dirithromycin is a semi-synthetic derivative of erythromycin - the hemi-aminal resulting from the condensation of (9S)-erythromycyclamine with 2-(2-methoxyethoxy) acetaldehyde. Being unstable under both acidic and alkaline conditions, dirithromycin functions as a more lipid-soluble prodrug for (9S)-erythromycyclamine. Erythromycylamine exerts its activity by binding to the 50S ribosomal subunits of susceptible mircoorganisms resulting in inhibition of protein synthesis. Dirithromycin has been shown to be active against most strains of the following microorganisms both in vitro and in clinical infections: Staphylococcus aureus (methicillin-susceptible strains only), Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenzae, Legionella pneumophila, Moraxella catarrhalis, and Mycoplasma pneumoniae. Dirithromycin showed better activity in vitro against Campylobacter jejuni and Borrelia burgdorferi than erythromycin or clarithromycin but in general demonstrated less activity than erythromycin, clarithromycin, or azithromycin against a majority of microorganisms. The pharmacokinetic profile of dirithromycin has advantages over other microlides of once-daily dosing and high and prolonged tissue concentrations but adverse effect profiles similar to those of the other macrolides, with reported problems most often related to the gastrointestinal tract.