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.

Guamecycline, a tetracycline derivative was studied in patients with broncho-pulmonary diseases and for the treatment of acute pneumopathies. However, information about the current use of this compound is not available.

Amicycline is an anti-bacterial agent, an antibiotic of tetracycline class.

There is a little information around sancycline. It is known, that it was synthesized by Conover and co-workers in 1962 and it was antibacterial compound. It was proposed that sancycline binds to the 30S of bacterial ribosomal subunit and inhibiting protein translation by blocking entry of aminoacyl-tRNA into the ribosome A site.

Etamocycline is a broad-spectrum antibiotic. It was studied in the treatment of bronchopulmonary and gastrointestinal infectious diseases.

Nitrocycline is a tetracycline antibiotic.

Demecycline is a tetracycline antibiotic drug. Tetracyclines have a broad spectrum of anti-microbial activity and act by interfering with bacterial protein synthesis. Demecycline is used to treat a wide range of infections caused by bacteria. Some of these infections are: Severe acne; Infections of the brain and liver caused by the bacteria Leptospira; Infection caused by Brucella bacteria (brucellosis); Infections caused by Rickettsiae micro-organisms transmitted by lice, fleas, ticks and mites; Infections of the sex organs and organs associated with urination (genito-urinary infections) such as an infection called chancroid, non-gonococcal urethritis; Rare infections such as Tularaemia and bubonic plague. The following undesirable effects have been reported for demecycline: loss of appetite, nausea, vomiting, diarrhea, inflammation of the tongue, difficulty in swallowing, intestinal inflammation, and inflammatory lesions, rashes, redness of the skin, pigmentation, sensitivity to light, acute kidney failure and others.

Cetocycline (formerly chelocardin or cetotetrine) is tetracycline derivative with potent antibacterial activity against a number of Gram-positive and Gram-negative multi-resistant pathogens. Cetocycline was found to be more active than tetracycline against many clinical isolates of aerobic gram-negative bacilli, but is less active against staphylococci, and has no activity against Pseudomonas. At low concentrations, like classical tetracyclines, chelocardin induces the proteomic signature for peptidyl transferase inhibition demonstrating that protein biosynthesis inhibition is the dominant physiological challenge. At higher concentrations B. subtilis mainly responds to membrane stress indicating that at clinically relevant concentrations the membrane is the main antibiotic target of chelocardin.

Meclocycline is a tetracycline antibiotic. It is used topically for skin infections treatment. Tetracyclines are broad-spectrum bacteriostatic agents and act by inhibiting protein synthesis by blocking the binding of aminoacyl tRNA (transfer RNA) to the mRNA (messenger RNA) ribosome complex. Meclocycline might increase sensitivity to light when it is used with Aminolevulinic acid.