Steroidal esters

Water-soluble complexes of .alpha.-6-deoxy-5-hydroxytetracycline and sodium tetrametaphosphate and their use

Selective solvolysis

Antibiotic derivatives

Esters of 16.alpha.- or 16.beta.-methyl-9.alpha.-chloro- or -fluorosteroids with high topical activity

Alkali metal polymetaphosphate complexes of hydroxytetracycline.alpha.-6-deoxy-5-

Recovery of doxycycline and products

Polyphosphate complexes of 6-demethyl-6-deoxy-6-methylenetetracycline and its 11a-halo derivatives

Alkali methal polymetaphate complexes of doxycycline

Esters and ethers of 16-methyl-9.alpha.-halocorticosteroids

Antibiotic derivatives

Preparation of steroids