359 Polypeptides and Related Compounds 



acid, C,H,„0,. m.p. 65', [al„''^ -21° (c 1.25 in chloroform), 

 and N-methyl-L-valine on acid hydrolysis. 



The enniatins also uniformly contain d( — )-a-hydroxy- 

 isovaleric acid, but each contains a characteristic 

 N-methylamino acid. (cf. valinomycin, amidomycin). 



A. H. Cook, S. F. Cox, T. H. Farmer and M. S. Lacey, Nature 

 160 31 (1947). 



A. H. Cook, S. F. Cox and T. H. Farmer, ibid. 162 61 (1948). 



Idem., J. Chem. Soc, 1022 (1949). 



751 Chlorine-containing Peptide, C2.-,H:{,,0sN-,CL, white needles, m.p. 



251° (dec), [a],/'' -92.9° (in methanol). 



Positive biuret and Pauly reactions, negative Sakaguchi, 

 Neubauer-Rhode, ninhydrin, Millon reactions. 



Acid hydrolysis yielded serine (2 to 3 moles), a-amino- 

 butyric acid (1 mole), ^-phenyl-/?-aminopropionic acid 

 ( 1 mole ) and an unidentified substance yielding a posi- 

 tive Ehrlich reaction. 



Penicilliinn islandicum Sopp. 



Yoshita Kobayashi, Kenji Uraguchi, Takashi Tatsuno, 

 Fuminori Sakai, Michio Tsukioka, Yutaka Sakai, Osamu 

 Yonemitsu, Taiko Sato, Masashi Miyake, Mamoru Saito, 

 Makoto Enomoto, Toshio Shlkata and Toshitaka Ishlko, Proc. 

 Japan Acad. 34 736 (1958). 



752 Pyridomycin, C26-27H32OSN4, colorless needles, m.p. 218-222°. 



Apparently rather closely related to etamycin. Alka- 

 line fusion yields : 



OH CH3 CH2CH.3 



, glycine and HOOC— CHCH— COOH 



COOH '^' OH 



Acid hydrolysis yields : 



OH 



, threonine and another degradation product incor- 

 •-%^i;:^\ porating picoline and glycine 



■COOH 



Streptomyces pyridomyceticus 



Kenji Maeda, J. Antibiotics (Japan) lOA 94 (1957) and 

 earlier papers in the series. 



753 Levomycin, Co7H:^sOtoN,; (proposed), colorless crystals, m.p. 222- 

 224°, [a],r' -323° (c 1 in chloroform). 



A polypeptide containing an aromatic group. 

 Streptomyces sp. 



