Delafloxacin (CAS registry number 189279-58-1) was described as WQ-3034 by Wakunaga Pharmaceutical Co., Ltd., Osaka & Hiroshima, Japan. It was first licensed in 1999 to Abbott Park, IL, and further developed as ABT-492. Delafloxacin (Baxdela), a fluoroquinolone antibiotic, is currently being developed by Melinta Therapeutics. It is a novel investigational fluoroquinolone in development for the treatment of uncomplicated gonorrhea, and acute bacterial skin and skin structure infections. Delafloxacin shows MICs remarkably low against Gram-positive organisms and anaerobes and similar to those of ciprofloxacin against Gram-negative bacteria. It remains active against most fluoroquinolone-resistant strains, except enterococci. Its potency is further increased in acidic environments (found in many infection sites). Delafloxacin is active on staphylococci growing intracellularly or in biofilms. Delafloxacin is a dual-targeting fluoroquinolone, capable of forming cleavable complexes with DNA and topoisomerase IV or DNA gyrase and of inhibiting the activity of these enzymes in both Gram-positive and Gram-negative bacteria. On Oct 24, 2016, Melinta Therapeutics Submitted Baxdela New Drug Application for hospital-treated skin infections.

Cefixime, an antibiotic, is a third-generation cephalosporin like ceftriaxone and cefotaxime. Cefixime is highly stable in the presence of beta-lactamase enzymes. As a result, many organisms resistant to penicillins and some cephalosporins due to the presence of beta-lactamases, may be susceptible to cefixime. The antibacterial effect of cefixime results from inhibition of mucopeptide synthesis in the bacterial cell wall. Like all beta-lactam antibiotics, cefixime binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, causing the inhibition of the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that cefixime interferes with an autolysin inhibitor. Cefixime is sold under the brand name Suprax, indicated for the treatment of: Uncomplicated Urinary Tract Infections Otitis Media Pharyngitis and Tonsillitis Acute Exacerbations of Chronic Bronchitis Uncomplicated Gonorrhea (cervical/urethral)

Gepotidacin (formerly GSK2140944) is a novel, first-in-class, triazaacenaphthylene antibacterial that selectively inhibits bacterial DNA gyrase and topoisomerase IV by a unique mechanism, one that is not utilized by any currently approved human therapeutic agent. As a consequence of its novel mode of action, gepotidacin is active in vitro against target pathogens carrying resistance determinants to established antibacterials, including fluoroquinolones. Gepotidacin has demonstrated in vitro activity against key pathogens, including drug-resistant strains, associated with a range of conventional and biothreat infections. GlaxoSmithKline is developing Gepotidacin for the treatment of gonorrhoea and skin and soft tissue infections.

Grepafloxacin, (S)- is an asymmetric fluoroquinolone derivative which possesses high tissue penetrability as well as strong, broad-spectrum antimicrobial activities. Grepafloxacin has a chiral center and therefore has two optical enantiomeric isomers, R(+)- and S(-)-grepafloxacin. In neutrophil respiratory burst induced by N-formyl-methionyl leucyl-phenylalanine grepafloxacin induces a priming effect. The R(+) enantiomer of grepafloxacin induced a more potent priming effect than did S(-)-grepafloxacin. R(+)-Grepafloxacin also produced a more potent translocation of both p47- and p67-phox proteins to membrane fractions of neutrophils. Grepafloxacin-induced primed superoxide generation was significantly inhibited by pretreatment with PD169316 and SB203580, p38 mitogen-activated protein kinase (MAPK) inhibitors, but not with PD98059, a specific inhibitor of the upstream kinase that activates p44/42 MAPK, or SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (JNK).

Grepafloxacin, (R)- is an asymmetric fluoroquinolone derivative which possesses high tissue penetrability as well as strong, broad-spectrum antimicrobial activities. Grepafloxacin has a chiral center and therefore has two optical enantiomeric isomers, R(+)- and S(-)-grepafloxacin. In neutrophil respiratory burst induced by N-formyl-methionyl leucyl-phenylalanine grepafloxacin induces a priming effect. The R(+) enantiomer of grepafloxacin induced a more potent priming effect than did S(-)-grepafloxacin. R(+)-Grepafloxacin also produced a more potent translocation of both p47- and p67-phox proteins to membrane fractions of neutrophils. Grepafloxacin-induced primed superoxide generation was significantly inhibited by pretreatment with PD169316 and SB203580, p38 mitogen-activated protein kinase (MAPK) inhibitors, but not with PD98059, a specific inhibitor of the upstream kinase that activates p44/42 MAPK, or SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (JNK).

Norfloxacin is an antibacterial agent, It inhibits inhibits DNA synthesis by inhibiting DNA gyrase enzyme. Norfloxacin was approved in 1986 for treatment of urinary tract infections, gynecological infections, prostatitis, gonorhhea and bladder infections. In ophtalmology, norfloxacin is used for treatment of conjunctivitus.

Ceftizoxime is a semisynthetic cephalosporin antibiotic, which can be administered intravenously or intramuscularly. It was sold under brand name, cefizox, but was removed from the US Market in 2007. Cefizox was used to treat different infections, such as lower respiratory tract infections caused by Klebsiella spp.; Proteus mirabilis; Escherichia coli; Haemophilus influenza; urinary tract Infections caused by Staphylococcus aureus (penicillinase¬ and nonpenicillinase¬producing); Escherichia coli; Pseudomonas spp. Also for treatment of gonorrhea including uncomplicated cervical and urethral gonorrhea caused by Neisseria gonorrhoeae; pelvic inflammatory disease caused by Neisseria gonorrhoeae, Escherichia coli or Streptococcus agalactiae; meningitis caused by Haemophilus influenza. In addition, some others infections. Cefizox has also been used successfully in the treatment of a limited number of pediatric and adult cases of meningitis caused by Streptococcus pneumoniae. Infections caused by aerobic gram ¬negative and by mixtures of organisms resistant to other cephalosporins, aminoglycosides, or penicillins have responded to treatment with Cefizox. The bactericidal action of ceftizoxime results from inhibition of the third and last stage of bacterial cell wall synthesis. Bacterial cell wall autolytic enzymes such as autolysins then mediate cell lysis; it is possible that ceftizoxime interferes with an autolysin inhibitor. Ceftizoxime is highly resistant to a broad spectrum of beta -lactamases (penicillinase and cephalosporinase), including Richmond types II, III, TEM, IV, produced by both aerobic and anaerobic gram - positive and gram - negative organisms and I.

Bacampicillin is a penicillin antibiotic. It is a prodrug of ampicillin with improved oral bioavailability. It exerts bactericidal activity via inhibition of bacterial cell wall synthesis by binding one or more of the penicillin binding proteins (PBPs). Spectrobid is used to treat bacterial infections such as tonsillitis, pneumonia (lung infection), bronchitis (inflammation of airway), urinary tract infections, gonorrhea, and infections of the skin. Adverse effects are: anemia, thrombocytopenia, neutropenia, agranulocytosis, seizures, nephrotoxicity, Jarisch-Herxheimer Reaction (fever, chills, sweating, tachycardia, hyperventilation, flushing, and myalgia). Drug interactions: Contraceptives - decreased contraceptive effectiveness; Live Typhoid Vaccine - decreased immunological response to the typhoid vaccine; Probenecid - increased bacampicillin levels.

Phenylmercuric ammonium acetate is a fungicide and bactericide. It is used for the seed treatment.

Solithromycin is a highly potent next-generation macrolide, the first fluoroketolide, which has potent activity against most macrolide-resistant strains. In vitro and in vivo studies have shown potent activity against S. pneumoniae as well as an extended spectrum of activity against CA-MRSA, enterococci, Mycobacterium avium and in animal models of malaria. It is also active against atypical bacteria, such as Legionella, Chlamydophila, Chlamydia, Mycoplasmaand Ureaplasma and against gonococci and other organisms that cause genitourinary tract infections. It is 8-16 times more potent than azithromycin and is active against azithromycin-resistant strains. Its activity against resistant strains is driven by its ability to bind to three sites on the bacterial ribosome, compared to one or two for current macrolides. It binds to the large 50S subunit of the ribosome and inhibits protein biosynthesis. The binding to three ribosomal sites is expected to limit resistance development. On July 2016 Cempra Announces FDA Acceptance of IV and oral formulations of Solithera (solithromycin) New Drug Applications for in the treatment of community-acquired bacterial pneumonia.