204 



DESCRIPTIONS OF ANTIBIOTICS 



trum given in reference 2. C54H82N2O1S : C = 

 62.03%; H = 7.83%; N = 2.73%; C-CH3 = 5.48%. 

 No methoxyl or acetyl groups. Light- and heat- 

 labile. Most stable at neutrality. Sodium salt: 

 [Q.]f = -2590° (water). Hi/drochlonde: [ar]'f = 

 + 140° (c = 0.4 per cent in dimethylformamide). 



Biological activiti/: Active on yeasts and fila- 

 mentous fungi (1). 



Toxicity: LD50 (mice) 2.25 mg per kg subcu- 

 taneously, and 14 mg per kg orally (1). 



References: 



1. English, A. R. and McBride. T. J. Antibi- 



otics Ann. 893-896, 1957-1958. 



2. Koe, B. K. et al. Antibiotics Ann. 897- 



905, 1957-1958. 



Antibiotic PA 153 



Produced by: Streptomyces sp. (2). 



Method of extraction: Same as antibiotic PA 

 150 (2). 



Chemical and physical properties: Amphoteric 

 pentaene. Colorless needles e.xhibiting strong 

 gray-green fluorescence under ultraviolet light. 

 Solubilities and melting point same as PA 150. 

 Ultraviolet absorption spectrum maxima at 303, 

 317, 332, and 349 niM (fi'Lm 1445) (80 per cent aque- 

 ous methanol). Infrared spectrum given in refer- 

 ence 2. [ry\f = +398° (pyridine) or +353° (di- 

 methylformamide-0.1 A' HCl). Positive ninhydrin, 

 2,4-dinitrophenylhydrazine, and Fehling tests. 

 Violet color in concentrated H2SO4 . C.htHbiNOh : 

 C = 59.94%; H = 8.29%; N = 1.88%,; C-CH3 = 

 6.01%. No methoxyl or acetyl groups. Heat- and 

 light-labile. Most stable at pH 7 to 10. Sodium 

 suit: [a]f = +205° (methanol). Hydrochloride: 

 [a]'^ = +283° (c = 0.4 per cent in dimethylform- 

 amide). 



Biological activity: Moderately active on yeasts 

 and filamentous fungi (1). 



Toxicity: LDso (mice) >200 mg per kg subcu- 

 taneously and >400 mg per kg orally (1). 



References: 



1. English, A. R. and McBride, T. J. Antibi- 



otics Ann. 893-896, 1957-1958. 



2. Koe, B.K. etal. Antibiotics Ann. 897-905, 



1957-1958. 



Antibiotic PA 155A 



Produced by: Streptomyces albus (2). 



Method of extraction: Extraction of l)roth with 

 ethyl acetate. Solvent concentrated and treated 

 with an excess of heptane to precipitate the crude 

 antibiotic. Countercurrent distribution in the sys- 

 tem benzene-methanol-water (2:1:1). Active frac- 

 tions chromatographed on acid-washed alumina in 



ethyl acetate. Elution with 2 to 5 per cent metha- 

 nol in ethyl acetate. Concentration of the solvent 

 gives a colorless crystalline solid (1). 



Chemical and physical properties: Very weak 

 base. Suggested empirical formula: C14H15O2N3 . 

 Colorless rectangular prisms; in.]). 209-210°C. 

 [a]f = —214° (c = 2 per cent in methanol). Max- 

 ima of light absorption at 218, 273, 281, and 288 

 m^i. Spectrvmi similar to that of tryptophan. 

 Slightly soluble in water, benzene, and ether. 

 Moderately soluble in lower alcohols and acetone. 

 Negative FeCls , ninhydrin, and 2,4-dinitrophen- 

 ylhydrazine reactions. Deep blue color with 

 Ehrlich reagent in strong alkali. Bromine water 

 decolorized. Positive neutral permanganate reac- 

 tion. Infrared absorption spectrum given in ref- 

 erence 1. Crystalline picrate contains 2 moles of 

 picric acid to 1 mole of PA 155A. Stable for 1 

 hour at 100°C in the pH range 2.0 to 8.0. Not 

 stable at an alkaline pH (1). 



Biological activity: Active against gram-positive 

 bacteria. 



References: 



1. Rao, K. V. Antibiotics & Chemotherapy 



10: 312-315, 1960. 



2. Marsh, W. S. et al. Antibiotics & Chemother- 



apy 10: 316-319, 1960. 



Antibiotic PA 166 



Produced by: Streptomyces sp. (2). 



Method of extraction: Same as antibiotic PA 

 150 (2). 



Chemical and physical properties: Amphoteric 

 tetraene. Colorless needles. Same solubilities and 

 melting point as PA 150. Ultraviolet absorption 

 spectrum maxima at 291, 304 {E\f^ 1098), and 319 

 m/x (80 per cent acjueous methanol). Infrared 

 spectrum given in reference 2. Same test reactions 

 as PA 153. C3 5Hs:,NO,4 : C = 59.59%,; H = 7.66%; 

 N = 2.00%; C-CHs = 6.77%. No methoxyl or 

 acetyl groups. Light- and heat-labile. Most stable 

 from pH 7.0 to 10.0. Sodium salt: [a if = +194° 

 (methanol). Hydrochloride: [a]i, = +239° (di- 

 methylformamide) (2) . 



Biological activity: Active on yeasts and fila- 

 mentous fungi. No activity in mice on C. albicans 



(1). 



Toxicity: LDsn (mice) >800 mg per kg subcu- 

 taneously, >1000 mg per kg orally. Nonirritating 

 topically in rabbits (1). 



References: 



1. English, A. R. and McBride, T. J. Antibi- 



otics Ann. 893-896, 1957-1958. 



2. Koe, B.K. et al. Antibiotics Ann. 817-905, 



1957-1958. 



