Chlortetracycline (trade name Aureomycin, Lederle) is a tetracycline antibiotic, the first tetracycline to be identified. It was discovered in 1945 by Benjamin Minge Duggar working at Lederle Laboratories under the supervision of Yellapragada Subbarow. Duggar identified the antibiotic as the product of an actinomycete he cultured from a soil sample collected from Sanborn Field at the University of Missouri. The organism was named Streptomyces aureofaciens and the isolated drug, Aureomycin, because of their golden color. Chlortetracycline inhibits cell growth by inhibiting translation. It binds to the 16S part of the 30S ribosomal subunit and prevents the amino-acyl tRNA from binding to the A site of the ribosome. In veterinary medicine, chlortetracycline is commonly used to treat conjunctivitis in cats.

Fumoxicillin was developed as an antibacterial agent that binds to penicillin-binding protein and inhibits the bacterial cell wall biosynthesis. Information about the current development of this compound is not available.

Levopropylcillin – is a penicillin derivative, L-enantiomer of antibiotic Propicillin. Levopropylcillin properties are similar to benzylpenicillin particularly used in streptococcal infections, not resistant to penicillinase. Levopropylcillin is acid resistant and can be used orally as the potassium salt.

Implitapide is a microsomal triglyceride transfer protein (MTP) inhibitor with antihyperlipidemic activity. Microsomal triglyceride transfer protein (MTP) is essential for the synthesis of both chylomicron in the intestine and very low-density lipoprotein in the liver. In an animal model, inhibition of MTP by implitapide reduced both total cholesterol and triglyceride levels and suppressed progression of atherosclerotic lesions in apolipoprotein E knockout mice fed a Western-type diet.

Piroxicillin is a broad-spectrum antibiotic. In vitro it is more active than piperacillin, apalcillin and mezlocillin especially against the following strains; E. coli, Ps. aeruginosa, Ps. stutzeri, K. pneumoniae, Eb. cloacae, Ser. marcescens, Proteus, Sh. flexneri, Y. enterocolitica, Cb. freundii, Acb. calcoaceticus, Bacteroides and Sc. faecalis. It shows very low MIC values against clinically important Gram-negative bacteria, primarily Pseudomonas aeruginosa. The action of piroxicillin is bactericidal.

Adicillin (Penicillin N) is a penicillin derivative produced by Cephalosporium acremonium. Adicillin is dextrorotatory. Inactivated by penicillinase as is penicillin G, but differs from the common penicillin by its antibacterial activity and hydrophilic character. Active against Sarcina lutea, Proteus vulgaris, Salmonella typhimurium, Diplococcus pneumoniae. Shows practically no activity against B. subtilis and Staph. aureus. The toxicity is somewhat less than that of penicillin G, although penicillin N is excreted more slowly.

Suncillin is an antibacteria and antifungal agent produced in Phytera's laboratory from a cell culture of a plant. Suncillin was patented by Bristol-Myers Co. In 1968 for the Pseudomonas bacteria treatment but was never marketed.

Quinacillin is semisynthetic penicillase-resistant penicillin patented by Boots Pure Drug Co. Ltd. For the treatment of bacterial infection. Quinacillin binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This interrupts bacterial cell wall synthesis and results in the weakening of the bacterial cell wall, eventually causing cell lysis. In clinical trials Staph. aureus was eradicated from all but two patients during treatment but recurred in 4 after withdrawal. The antibiotic was especially useful in the treatment of staphylococcal respiratory infections, as it has little effect on the normal bacterial flora of the chest.

Fuzlocillin is a penicillin antibiotic. This semisynthetic acylureidopenicillin with antibacterial activity binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. Fuzlocillin (furazlocillin), has been shown to be highly specific for the FtsI gene. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This interrupts bacterial cell wall synthesis and results in the weakening of the bacterial cell wall, eventually causing the cell to break down (cell lysis). Among the acylureidopenicillins, furaclocillin exerts increased activity against Escherischia coli, Klebsiella, Proteus and Pseudomonas aeruginosa.