DESCRIPTIONS OF ANTIBIOTICS 



389 



217°C (decomposition). Basic substance. Soluble 

 in methanol, ethanol, butanol, ethyl acetate, 

 butyl acetate, ether, dioxane, chloroform, and 

 acetone. Insoluble in water and petroleum ether. 

 C = 60.0%; H = 8.4%; N = 2.5%. No S or halogen 

 detected. C42H69NO16 (2). Negative ninhydrin, 

 biuret, Benedict, Sakaguchi, xanthoproteic, 

 FeCls , nialtol, and Fehling tests. Positive Molisch 

 and Seliwanoff reactions. Reddish orange color 

 when added to 40 per cent sulfuric acid. Ultra- 

 violet light-absorption at 233 m/j. (El'tm 316) in 

 ethanolic solutions. [a]J,' = —44° (c = 1 per cent 

 in ethanol) and —49° (c = 1 per cent in chloro- 

 form) (1). Paper chromatographic data given in 

 reference 1. Black precipitate with Tollen's re- 

 agent. Acetyl derivative: m.p. 212-217°C (decom- 

 position) or 210-215°C (decomposition). Thiosenii- 

 carbazone: m.p. 198°C (2). 



Biological activity: Active against gram-positive 

 bacteria. No activity against gram-negative bac- 

 teria, or fungi (1). Acetyl derivative: Less active 

 than parent compound on Staph, aureus and B. 

 siibtilis (2). 



Toxicity: Mice tolerate 415 nig per kg intra- 

 peritoneally (1). 



References: 



1. Osato, T. et al. J. Antibiotics (Japan) 8A: 



105-109, 1955. 



2. Miyake, A. et al. J. Antil)iotics (Japan) 



12A: 59-64, 1959. 



Tertiomyciiv B 



Produced by: Streptomyces eurocidicus. 



Synonym: Related to antibiotic 446. 



Method of extraction: Culture-filtrate extracted 

 with butyl acetate at pH 7.5. Solvent evaporated 

 in vacuo to syrup; washed with petroleum ether. 

 Residue dried in vacuo; extracted with carbon 

 tetrachloride, and the solvent solution passed 

 through an alumina column. Elution with ethyl 

 acetate. Evaporation of solvent. Residue dis- 

 solved in hot benzene; concentration and cooling 

 of benzene solution yields crystalline tertiomycin 

 B. 



Chemical and physical properties: Basic sub- 

 stance. White needle-shaped crystals; m.p. 97- 

 99°C. Light-absorption maxima at 231 {E{1„, 237) 

 and 278 m/x {Ei\n 1.8) in ethanolic solution. [a]j^ = 

 —56° (c = 1 per cent in ethanol). Tentative em- 

 pirical formula: C43H71NO17 . Negative Fehling, 

 ninhydrin, Liebermann, and FeClj reactions. Posi- 

 tive Tollen and Molisch reactions. Light reddish 

 brown color with 40 per cent sulfuric acid. 



Biological activity: Inhibits the growth of gram- 

 positive bacteria at concentrations of 0.1 to 3 ng 



per ml. Very little activity against mycobacteria. 

 Inactive against the gram-negative bacteria and 

 fungi tested. 



Toxicity: LD50 about 250 mg per kg intrave- 

 nously (animal used not stated). 



Reference: 1. Osato, T. et al. J. Antibiotics 

 (Japan) 8A: 161-163, 1955. 



Tetracycline 



Produced by: Streptomyces aureofaciens strains 

 (21, 25). (Tetracycline is produced instead of 

 chlortetracycline when bromide is adtled to the 

 medium to inhibit chloride utilization, or when 

 the chloride ions are removed from the medium 

 (19, 25).) S. sayamaensis (24) (vmder the same con- 

 ditions as above), S. viridifaciens (21, 31), S.feo- 

 faciens (33), Streptomyces sp. (36,38), S. persimi- 

 lis (39), and catalytic dehalogenation of chlor- 

 tetracycline (2, 4, 20). 



Synonym: Antibiotic HA 20A (25). 



Method of extraction: lA: Broth-filtrates, after 

 treatment with sequestering agents to remove 

 excess polyvalent metallic ions, are extracted with 

 butanol or methyl isobutyl ketone at pH 8.5 in 

 the presence of either 0.5 per cent CaCU or a 

 wetting agent such as the Tergitols or Aerosols. 

 Organic extract concentrated, and mixed with 

 Skellysolve C to precipitate the free base, or con- 

 verted to an acid-salt. Purified by extracting with 

 NH4OH and chromatography on Florisil, washing 

 with acetone or methanol, and elution with dilute 

 acid (26, 31, 35). IB: Whole culture treated with 

 oxalic acid, pH adjusted to 3.5 with NH4OH, 

 and filtered. N-(Lauroylcolaminoformylmethyl) 

 pyridinium chloride ("Emulsept") in ethyl ace- 

 tate is added to the filtrate, pH adjusted to 8.5, 

 and the whole stirred. Organic layer extracted 

 with acidic water (pH 1.7). Extract adjusted to 

 pH 7.8 with NH4OH to give tetracycline (25). 

 IIA. Precipitated from broth at pH 10.0 with 

 high molecular weight quaternary ammonium 

 compounds such as the "Arquads" (see oxytetra- 

 cycline). This precipitate, which is a complex 

 salt composed of tetracycline, the organic base, 

 and polyvalent metallic ions (either present in or 

 added to broth), is slurried with water-chloroform 

 at pH 10.5. Organic phase extracted with aqueous 

 acid at pH 1.2 to 2.5 as in IB (25). IIB. The 

 precipitated complex in IIA may be added to 

 methanol, kept at pH 2.0 to 2.5, and CaCla added. 

 Addition of further acid gives the tetracycline 

 acid-salt ; raising the pH from 5 to 7 gives free tetra- 

 cycline (25, 34). III. Whole culture acidified to 

 pH 1.0 to 2.0 and filtered. Filtrate adjusted to 

 pH 7.5 to 8.0 to pi'ecipitate crude tetracycline. 



