General Characteristics of the Tetracyclines

Following are the general characteristic features of all the members of the tetracycline family  

In neutural solutions these substances exist mainly as Zwitter ions. 

The strong bases on the other hand promote a reaetion between the hydroxyl group at C-6 and the earbonyl moiety at C-11, thereby causing the bond between C-11 and C-1 la atoms to cleave and eventually form the lactone ring found in the inactive isotetracyclines. 

A few typieal examples of the tetracyclines shall be dealt with in the sections that follows  

The drug is the durg of choice in the treatment of ehloera, relapsing fever, granuloma inguinale and infeetions produced by rickettsia, Borrelia, Mycobacterium fortuitum and marinum, and Chlamydia psittaci and trachomatis (except pneumonia and inclusion conjunctivitis). 

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