180 THE ANTIBIOTICS 



d 2 . Incompletely described substances. 

 a 8 . Toxic to mice. 



hitmocidin 

 b 3 . Relatively nontoxic to mice. 



Coelicolorin 



2. Nonpigmented. 



a. Containing sulfur. 



a 1 . Active against mycobacteria. 



Cinnamydn 

 b 1 . Inactive against mycobacteria. 



Sulfactin 



b. Containing no nitrogen and no sulfur, acidic. 



Antibiotics X-206, X-464 and X-537A 



c. Containing nitrogen but no sulfur. 



a 1 . Basic; typical light-absorption spectra. 



a 2 . Partly soluble in water. Peak of maximum absorption 

 at 240 van. 



Carbomycin 

 b*. Insoluble in water. Peaks of maximum absorption at 

 250 and 320 m/x. 

 Nitrosporin 

 b l . Basic; without typical light-absorption spectra. 

 Proactinomycin 

 Picromycin 



3. Incompletely described. 



Micromonosporin 

 Neonocardin 

 Cardicin 

 Griseoflavin 



B. Substances active against gram-positive and gram-negative bacteria. 



I. Not active against mycobacteria. 



1. Active also against fungi. See group C, pp. 182-183, for thiolutin 

 and microcins. 



2. Not active against fungi. 



a. Water-soluble. 



Grisein 



b. Soluble in organic solvents. 



Xanthomycins 

 II. Containing no nitrogen. 



1. Highly unstable unsaturated fatty acid. 

 Mycomycin 



