Pfizer Handbook of Microbial Metabolites 596 



Micromonospora sp. 



Tomotsune Taira and Shigehiro Fujii, J. Antibiotics (Japan) 

 5 187 (1952). 



1204 Mikamycin A, C31H39O9N3, yellowish white crystals, m.p. 147- 



152° (dec), [aln'" -152° (c 0.5 in methanol). 



Apparently identical with the principal active com- 

 ponent of the streptogramin and antibiotic No. 899 com- 

 plexes. 



A neutral antibiotic. Negative ninhydrin, biuret, glu- 

 cosamine, maltol and Millon. Green-black FeCla. Brown 

 precipitate with the Tollens reagent. Positive Benedict. 

 Forms a 2,4-DNPH. 



Streptomyces mitakaensis 



Mamoru Aral, Keiko Karasawa, Shoshiro Nakamura, Hiroshi 

 Yonehara and Hamao Umezawa, J. Antibiotics (Japan) 11 A 

 14 (1958). 



Mamoru Aral, Koichi Okabe, Hiroshi Yonehara and Hamao 

 Umezawa, ibid. IIA 21 (1958). 



Koichi Okabe, ibid. 12A 86 (1959). 



1205 Mikamycin B, C45H5sOiiNg (proposed), white platelets, m.p. 



160°, dec. 262°, [aW -61.3° (c 1.0 in methanol). 



Similar to PA-114 B in physical and chemical proper- 

 ties but differs from staphylomycin S. It is thought to be 

 different from both. 



Gives a positive FeClj. Negative Ehrlich, biuret, 

 Fehling, Tollens, nearly negative ninhydrin. 



Streptomyces mitakaensis 



Kiyoshi Watanabe, Hiroshi Yonehara, Nobuo Tanaka and 

 Hamao Umezawa, J. Antibiotics (Japan) 12A 112 (1959). 



Koyoshi Watanabe, ibid. 13A 57 (1960). 



Mitomycins. 



1206 A complex from which several compounds were iso- 



1207 lated: colorless fractions W-1 (m.p. 148°), W-2 (m.p. 



1208 138°) and W-3 (m.p. 187°). Pigmented fractions A (red 



1209 crystals) m.p. 167°, B (violet crystals), C (bluish violet 



1210 crystals), Y (yellow crystals) m.p. 180-240° (dec.) and 



1211 R (red-brown amorphous powder). Pigmented fractions 



1212 are antibiotic. 



1213 



1214 Mitomycin C, C54H61OJ9N13 (tentative), deep bluish violet crys- 

 tals, m.p.: no melting or dec. noted below 360°. 



