278 



DESCRIPTIONS OF AXTIlilOTICS 



Chemical and physical properties: Gancidin A.- 

 Basic substance. Orange columnar crystals. 

 Changes to dark orange at 110°C, then to black at 

 290°C. Soluble in chloroform, methanol, ethanol, 

 acetone, and water. Slightly soluble in ethyl 

 acetate, benzene, carbon tetrachloride, and ether. 

 Insoluble in petroleum ether. Ultraviolet absorp- 

 tion spectrum maxima at 205 niyu (-Eh-'m 324), 265 

 mM {E^L 248), and 340 m^ {E'lL 28) in 0.1 .V 

 HCl. Infrared absorption spectrum data given in 

 reference 1. Positive Fehling test. Negative nin- 

 hydrin, 2,4-dinitrophenylhydrazine, and FeCls 

 tests. More stable to heat at acid than at alkaline 

 pH. C43H58-60N6O14 : C = 58.7%; H = 6.68%; N = 

 9.49%. Molecular weight, 1002 (Rast) or 883. Hy- 

 drochloride: Needles. Gancidin W: Neutral sub- 

 stance. White platelets; m.p. 163-164 °C. Soluble 

 in methanol, ethanol, and acetone. Slightly solu- 

 ble in ethyl acetate, carbon tetrachloride, ether, 

 and water. Insoluble in petroleum ether. Ultra- 

 violet absorption spectrum maximum at 206 niM 

 {Eum 296). Infrared data given in reference 1. 

 Negative biuret, ninhydrin, Ehrlich, Fehling, 

 Benedict, Tollen, Molisch, 2,4-dinitrophenyl- 

 hydrazine, ferrous hydroxide, FeCls , and Brj 

 tests. CuHn.i902N2 : C = 63.04%; H = 8.7%; 

 N = 13.65%. Molecular weight, 210 (2). 



Biological activity: Later work did not confirm 

 early reports of good antitumor activity in vivo. 

 Gancidin A is said to resemble xanthomycin A in 

 certain respects (1,2). Gancidin A: Very active on 

 gram-positive bacteria. Active on Ehrlich ascites 

 carcinonui in vitro but not in vivo. Gancidin W: 

 No activity on B. subtilis. Very slight activity at 

 >5 mg per kg against Ehrlich ascites carcinoma 

 in mice (2). 



Toxicity: Gancidin A: LUsu (mice) 80 yug per kg 

 intravenously. Gancidin W: LDjo (mice) 80 mg 

 per kg intravenously (2). 



References: 



1. Aiso, K. et al. J. Antibiotics (Japan) 9A: 



97-101, 1956. 



2. Wakaki, S. et al. J. Antibiotics (Japan) 



llA: 150-155, 1958. 



COOH 



O— C CH— N 



I I II 



CH. CH. C— NHo 



NH.. 



^N^ 

 H 



Geonij fill 



Produced hy: Strains of StrcploiiiyccH .cantho- 

 phaeus (1, 3). 



Synonym: St rPi)tothricin-like antibiotic. 



Method of extraction: Broth-filtrate chroma- 

 tographed on IRC-50 (buffered with 0.2 M Na3P04 

 buffer at pH 6.5) and eluted with 0.5 \ HCl. Active 

 fractions adjusted to pH 6.0 with IR-4B, then 

 concentrated to dryness in vacuo. Adsorbed on 

 active carbon and eluted with weak H2SO4 (pH 2 

 to 3). Sulfate ions precipitated as Ba salt, and 

 antibiotic converted to an oily picrate. Purifica- 

 tion by salt conversion (hydrochloride — > heli- 

 anthate — + hydrochloride -^ base). Dried and 

 powdered myceliimi extracted with 1 ,V HCl- 

 methanol (1:1), then purified by adsori)tion on 

 IRC-50. 



Chemical ami physical properties: Complex: 

 Contains four to six closely related components, 

 varying with the producing strain. Faintly yellow 

 powder. Ultraviolet absorption spectrum shows 

 end-absorption only (water). Infrared spectrum 

 given in reference 3. Positive ninhydrin and Elson- 

 Morgan tests. Weakly positive Sakaguchi test and 

 tests for carbohydrates and sugars. Light blue 

 color with biuret test. Negative maltol, FeCls , 

 and 2,4-dinitrophenylhydrazine reactions. (CeHis- 

 02N2)s.iu : C = 49.48%; H = 8.91%; N = 20 to 

 25%. Acid hydrolysis products include NH;j , 

 CO2 , L-/3-lysine, and an amino acid, geamine, 

 which is isomeric with or identical to streptolidine 

 (roseonine) from streptothricin, streptolin, and 

 roseothricin (see streptothricin-like antil)iotic). 

 Geamine: C6H12O3N4 . Geamine dihydrochloride: 

 Colorless needles; m.p. 208-213°C. [a\l = +57.5° 

 (c = 1.9 per cent in H2O). Geomycin may contain 

 a peptide moiety made up of glutamic acid, as- 

 partic acid, serine, threonine, glycine, and alanine 

 (2-4). It contains at least four /3-lysine residues 

 connected at the e-amino groups. (Jeamine is 

 bound by its hydroxyl to a sugar or amino sugar 

 moiety (R). Partial structvu-e (5): 



NH,— CO— CH.— CH— [CH2]., 



I I 



NHo NH 



I 

 CHoCO- 



R 



NH[CH2]:rCH-CH2-CO-NH[CH2]3CHCH2CO-NH[CH2]3CH- 

 NHo NH2 NH2 



