176 THE ANTIBIOTICS 



III. Nonpigmented neutral compounds. 



1. Contain nonionic chlorine. 



a. Active against various bacteria, low toxicity. 

 Chloramphenicol 



D. Substances active primarily against yeasts and filamentous fungi. 



I. Pigmented substances, soluble in organic solvents. 



1. Insoluble in ether, slightly soluble in water; greenish yellow in 

 color. 



a. Weak base. .Fradicin 



b. Weak acid 



a 1 . Insoluble in water. 



Ascosin 



Candicidin B 

 b 1 . Soluble in water 



Candicidin A 



2. Insoluble in water, yellowish in color, separate into ether-soluble 

 (A) and ether-insoluble (B) fractions. 



Actinone 



3. Relatively insoluble in water and most organic solvents; yellow 

 powder; found in mycelium of Streptomyces sp. 



Nystatin 

 (Fungicidin) 



4. Fairly soluble in water; highly active against Coccidioides im- 

 mitis Antimycoin 



(Fungicidin RAW) 



5. Readily soluble in methanol and water containing butanol. 



Chromin 



6. Neutral and acid substances, active against fungi and bacteria. 



Microcin A, B 

 II. Nonpigmented substances. 



1. Insoluble in water, soluble in ether, weakly acidic phenol. 



Antimycin A 



2. Insoluble in water and ether; soluble in alcohols and methyl 

 cellosolve; heat-stable; antifungal and antibacterial. 



Endomycin 



Helixin A, B, C and D 



3. Acidic; insoluble in water and ether; unstable; antifungal and 

 antibacterial . . . Musarin 



4. Weakly acidic, containing glutarimide ring; soluble in water, 

 chloroform and ether. 



Cycloheximide 



