7- Chlortetracycline

Fig. 1. Tetracycline (1) and its derivatives chlortetracycline (7-chlorotetracycline) (2) oxytetracycline (5-hydroxytetracycline) (3), demeclocycline (6-demethyl-7-chlorotetracycline) (4) methacycline (6-demethyl-6-deoxy-5-hydroxy-6-methylenetetracycline) (5) doxycycline (6a-deoxy-5-hydroxytetracycline) (6) and minocycline (6-demethy1-6-deoxy-7-dimethy1 amino tetracycline) (7). Substituents at positions not specifically...

The first tetracycline discovered was produced by a soil organism, Streptomyces aureofiaciens and is now known as chlortetracycline [57-62-5] (2),... 

Anhydrotetracycline oxygenase from Streptomjces aureofaciens which cataly2es the conversion of anhydrotetracycline to dehydrotetracycline, has been isolated and characterized as a flavin-dependent oxygenase (83). It consists of two subunits of mol wt = 57, 500 based on SDS/polyacrylamide—gel electrophoresis. The cosynthetic factor 1 of Streptomjces aureofaciens involved in the reduction of 5a,lla-dehydrochlortetracycline to chlortetracycline, has been identified as 7,8-didemethyl-8-hydroxy-5-deazariboflavin. This work was aided by comparison of spectral data with that of an authentic sample obtained from the hydrolysis of coenzyme F-420 (84). 

The first three of these agents to be discovered, tetracycline (1) chlortetracycline (2), and oxytetracycline (3), ... 

Work on mutant cultures provided the first practical, although partial, solution to the dehydration phenomenon. A mutant strain whose parent produced chlortetracycline (2) was... 

A practical process had earlier been developed for the transformation of chlortetracycline (2) into tetracycline (1) by catalytic hydrogenolysis of the aromatic chloro group. Application of the reaction under suitable conditions to demethylchlortetra-... 

The production of tetracycline by catalytic dechlorination is described in U.S. Patent 2,699,054 as follows Pure chlortetracycline (4.8 grams) was suspended in 100 ml of methanol and sufficient anhydrous dioxane was added to completely dissolve the product. To the solution was added 0.5 gram of 5% palladium-on-charcoal catalyst. The mixture was placed in a conventional hydrogenation apparatus and subjected to a pressure of 50 psi of hydrogen while being agitated. 

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