The structure of Aureomycin was elucidated in 1952 and published in 1954 by the Pfizer-Woodward group. After the discovery of the structure, researchers at Pfizer began chemically modifying aureomycin by treating it with hydrogen in the presence of a palladized carbon catalyst. This chemical reaction replaced a chlorine moiety with a hydrogen, creating a compound named tetracycline via hydrogenolysis. Tetracycline displayed higher potency, better solubility, and more favorable pharmacology than the other antibiotics in its class, leading to its FDA approval in 1954. The new compound was one of the first commercially successful semi-synthetic antibiotics that was used, and laid the foundation for the development of Sancycline, Minocycline, and later the Glycylcyclines. Evidence in antiquity
Our modern understanding of tetracyclines dates their discovery to 1948, but there is evidence that early inhabitants of Northeastern Africa consumed tetracycline antibiotics. Nubian mummies from between 350 and 550 C.E. were found to exhibit patterns of fluorescence identical with that of modern tetracycline labelled bone.Tetracycline has a high affinity for calcium and is incorporated into bones during the active mineralization of hydroxyapatite. When incorporated into bones, tetracycline can be identified using ultraviolet light.It is conjectured that the beer brewed at the time was the source of the tetracycline found in these bones. Society and culture
Price
According to data from EvaluatePharma and published in the Boston Globe, in the USA the price of tetracycline rose from $0.06 per 250-mg pill in 2013 to $4.06 a pill in 2015.
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Commercially available minoxidil topical solution should be stored at a temperature of 20-25 °C. Extemporaneous formulations of minoxidil have been reported to have variable stability, depending on the vehicle and method of preparation, and the FDA requests that physicians and pharmacists refrain from preparing extemporaneous topical formulations using commercially available minoxidil tablets. Minoxidil tablets should be stored in well-closed containers at 15-30 °C. Minoxidil, 6-amino-1,2-dihydro-1-hydroxy-2-imino-4-piperidinopyrimidine, is synthesized from barbituric acid, the reaction of which with phosphorous oxychloride gives 2,4,6-trichloropyrimidine. Upon reaction with ammonium, this turns into 2,4-diamino-6-chloropyrimidine. Next, the resulting 2,4-diamino-6-chloropyrimidine undergoes reaction with 2,4-dichlorophenol in the presence of potassium hydroxide, giving 2,4-diamino-6-(2,4-dichlorophenoxy)-pyrimidine.