DESCRIPTIONS OF ANTIBIOTICS 



179 



kali. Slightly soluble in alcohol, acetic acid, ace- 

 tone, dioxane, tetrahydrofuran, and NaHCOs 

 solution. Insoluble in petroleum ether, ether, 

 carbon disulfide, carbon tetrachloride, and water. 

 Ultraviolet absorption spectrum maxima at 523 

 and 560 ni/n (dioxane), 573 and (Ul ni/x (concen- 

 trated H2S()4), and 588 and 641 niM (NaOH). Red 

 in acetic anhydride, becoming violet-blue with 

 red fluorescence on addition of boric acid with 

 warming. Red in dioxane. Deep blue in concen- 

 trated H2SO4 , becoming red-violet on addition 

 of boric acid. Bright blue in NaOH (1, 2). Forms 

 a yellow crystalline triacetate (clustered needles) , 

 which gives no absorption of visible light and de- 

 composes without melting at 260°C (2). In the 

 mycelium, it exists mainly as protoactinorhodin 

 (III). Ill is extracted from the dried mycelium 

 with acetone, and precipitates as pink, micro- 

 scopic prisms which turn red at 270°C and de- 

 compose at about 335°C (3). Partial structural 

 formula of actinorhodin (4) : 



rated NaCl. Eluate evaporated to dryness in 

 vacuo. Residue extracted with boiling methanol. 

 Cooling of extract precipitates crude actinorul)in. 

 Purified by chromatography on H2S04-treated 

 alumina, with 85 per cent methanol as solvent 

 and developer. Precipitates from active fractions 

 as helianthate (2). 



Chemical and physical properties: Basic sub- 

 stance: CeHuNsOo or C,H22Nr,04 . HCl salt: white 

 powder. Dihelianthate: reddish orange needle 

 clusters; m. p. 206-214°C. C = 51.40%; H = 5.93%; 

 N = 17.36%; S = 7.34 or 8.87%. Soluble in water 

 and methanol. Insoluble in ether. Positive biuret, 

 Fehling (on boiling), and KMn04 tests. Negative 

 Sakaguchi and Molisch tests. Dialyzable. Stable 

 to Ijoiling in aqueous solution at pH 6 to 7 for 

 15 minutes (2). Major component present in crude 

 preparation indistinguishable by paper chroma- 

 tography from pure streptothricin (wet butanol- 

 /3-toluenesulfonic acid) (4). 



W 



R2 



-H O 



Ri , R2 , R3 , R4 • 



2— COOH, 2— CH:, , CsHieO; 



Biological activity: Weakly active on Staph. 

 aureus (2). 

 References: 



1. Brockmann, H. and Pini, H. Naturwissen- 



schaften 34: 190, 1947. 



2. Brockmann, H. et al. Chem. Ber. }{.'}: 161- 



167, 1950. 



3. Brockmann, H. and Loescheke, V. Chem. 



Ber. 88: 778-788, 1955. 



4. Brockmann, H. and Hieronymus, E. Chem. 



Ber. 88: 1.379-1390, 1955. 



Acli 



iioriinin 



Produced by: A Strcptoiuyces sp. that produces 

 a red mycelium (1). 



Synonijm: Streptothricin-like substance. 



Method of extraction: Adsorbed from broth-fil- 

 trate on Decalso at pH 7.0 and elute<l with satu- 



Biological activity: Active on gram-positive and 

 gram-negative bacteria and mycobacteria. 

 Limited activity on B. cereus-niycoides group and 

 streptococci. Moderately active on Trichophyton 

 interdigiiale. Cross-resistance with lavendulin 

 and streptothricin (1). Active /// vivo (mice) on 

 K. pneumoniae infections (3). 



Toxicity: LDioo (mice) 73.9 mg per kg intra- 

 peritoneally (3). 



References: 



1. Kelner, A. and Morton, H. E. J. Bacteriol. 



53: 695-704, 1947. 



2. Junowicz-Kocholaty, R. and Kocholatj-, 



W. J. Biol. Chem. 168: 757-764, 1944. 



3. Morton, H. E. Proc. Soc. E.xptl. Biol. 



Med. 64: 327-331, 1947. 



4. Benedict, R. G. Botan. Rev. 19: 229-320, 



1953. 



