DESCRIPTIONS OF ANTIBIOTICS 



259 



with antimetabolic activity. Ciba Foun- 

 dation Symposium. Little, Brown and 

 Company, Boston, 1958, pp. 62-74. 



16. Krantz, S. et al . J. Natl. Cancer Inst. 



22: 433-439, 1959. 



17. Thiersch, J. B. Proc. Soc. E.xptl. Biol. 



Med. 94: 33-25, 1957. 



18. Magill, G. B. et al. Cancer 10: 1138-1156, 



1957. 



19. Potter, M. and Law, L. W J, Natl. 



Cancer Inst. 18: 413-442, 1957. 



20. Duvall, L. R. Cancer Chemotherapy 



Rept. 7:86-98, 1960. 



Dura 111 vein 



Produced by: Streptoniyces cintuvnonieus f. azaco- 

 luta (1,3). 



Synonym: Fraction B of antibiotic F 17(2). Cul- 

 ture-broths contain three or more antibiotics 

 (3) related to cinnamycin. 



Method of extraction: Broth extracted with buta- 

 nol. Addition of heptane causes separation of an 

 aciueous layer containing most of the antibiotic. 

 Concentration in vacuo of watery layer, followed 

 by lyophilization. Purified by chromatography 

 on alumina at pH 4.7 with 80 ])er cent ethanol as 

 solvent and developer (2). 



Chemical and physical properties: Slightly acidic 

 polypeptide. Soluble on heating in absolute metha- 

 nol, water-methanol, and water-ethanol. Forms a 

 crystalline picrate and alcoholate, and a helian- 

 thate. HCl: Solul)le in water, aqueou.s acetone, 

 methanol, and ethanol. Slightly soluble in alisolute 

 alcohols. Surface-active. Infrared data given in 

 reference 2. No ultraviolet absorption. {a]t~' = 

 — 6.4° (c = 3.9 per cent in water). No definite 

 melting point. Positive biuret and azide-iodine 

 tests. Negative FeCls , Benedict, Molisch, periodic 

 acid, Millon, nitroprusside, Pauly, Sakaguchi, 

 .xanthoproteic, and Hopkins-Cole tests. Stable to 

 heat at pH 3 to 9. Acid hydrolysates contain 

 lanthionine, /3-methylanthionine, aspartic acid, 

 glycine, glutamic acid, proline, valine, phenylala- 

 nine, and possibly ornithine and hydroxyproline. 



Contains several free carljoxyl and at least one 

 free amino group. Picrate: m.p. 212-245°C (decom- 

 position). Insoluble in absolute methanol; soluble 

 in water-saturated butanol. C = 51.30%; H = 

 5.76%; N = 16.85%; S = 3.18% (2). 



Biological activity: Active on gram -positive rods; 

 less active on fungi and yeasts (2). 



References: 



1. Pridham, T. G. et al. Phytopathology 46: 



575-581, 1956. 



2. Shotwell, O. L. et al. J. Am. Chem. Soc. 



80: 3912-3915, 1958. 



3. Lindenfelser, L. A. et al. U. S. Patent 



2,865,815, December 23, 1958. 



Ecliiiioniycin 



Produced by: Streptomyces echinatus (2) and an 

 unidentified Streptomyces sp. (4). 



Synonyms: Antibiotic X 948 (1, 4). May be 

 related to actinoleukin (5). 



Method of extraction: Culture-filtrate extracted 

 at pH 7 to 8 with ethyl acetate; extract freed from 

 inactive bases and acids and concentrated in 

 vacuo. Active substance precipitated with petro- 

 leum ether and purified by chromatography over 

 alumina. Crystallization from methyl alcohol (3). 



Chemical and physical properties: Weakly basic 

 (3). Colorless powder, m.p. 217-218°C (3); or 

 colorless prisms, m.p. 236-238°C (4). Soluble in 20 

 per cent HCl, but not in other dilute mineral acids. 

 Ultraviolet absorption spectrum maximum 243 

 ni/Li (log e = 3.81). Infrared spectrum given in 

 reference 3. [ajo = —310° (c = 0.86 per cent in 

 CHCI.3) (3). Negative tests for thio- and disulfide 

 groups (6). CosHstOtNtS (3, 4) or C,-,ij-62H6o-64- 

 O12N10S2 : C = 55.45%; H = 5.88%; N = 15.33%; 

 S = 5.27%; N-CH3 = 5.2%; C-CH3 = 2.75%. 

 Molecular weight, 1050 ± 50 or 1604 ± 30 (6). 

 Acid hydrolysis products include D -serine, 

 L-alanine, L-N-methyl valine, and N-methyl-N'- 

 phenylthiourea. Alkaline hydrolysis yields cjuin- 

 oxaline-2-carboxylic acid (3, 6). Probable struc- 

 tvu'al formula (6) : 



.N, 



CH3 



CHs 



H3C 



\ / 

 CH3 CH 



CH3 



f^^^^ S— CO— NH— CH— CO— NH— CH— CO— N— C— CO— N CH— CO-O-CH, 



^N^ 



S CH2 



I I 



CH2 s 



CH,— O— CO— CH— N— CO — C— N— CO— CH-NH-CO-CH-NH-CO ^ ^ 



II II 



HC CH3 CH3 CH3 



/ \ 

 HsC CH3 



