371 Polypep tides and Related Compounds 



Streptornyces echinatus n. sp. 



R. Corbaz. L. Ettlinger, E. Gaumann, W. Keller-Schierlein, 

 F. Kradolfer, L. Neipp, V. Prelog, P. Reusser and H. Zahner' 

 Helv. Chim. Acta 40 199 (1957). (Isolation) 



W. Keller-Schierlein, M. Lj. Mikhailovich and V Prelog 

 iWd. 42 305 (1959). (Structure) 



Circulins, C-,3Hi„„Oi3Ni(5 (Sulfate), amorphous solid, m.p. 226- 

 228° (dec), [«]„" -61.6°. 



776 Circulin A: 



CHs O 



I II 



CH3CH2CHCH2CH2CH2CH2— C— NH 



NH2 ^"- NHo* 



\ ru O / 



CH ^CH O 



% / \ 



CH. C NH 



CH3 



CH3 



CH3 / 



NH 



CH' 



CH L-Isoleu t-Thre CH' 



\ OH 



c==o 



0=C NH 



-„.^CH D-Leu l-Dia CH 



,CH2 \^ / 



CH2 



^CHo 



/ NH C^ --KJU 



CH^ L-Thre CH 



CH2 N"^^ ^-Dia ^C^ \ „ ^^ 



CH2 o' J.^ O CH3 



H2N 



/ 



CH2 

 CH2 



I 



NHo 



Bacillus circulans 



Hydrolysis yields 6 moles of L-a, y-diaminobutyric acid, 

 2 moles of L-threonine, 1 mole of D-leucine, 1 mole of 

 L-isoleucine and 1 mole of ( + )6-methyloctanoic acid. 



'7 Circulin B has essentially the same structure, but the 6-methyl- 

 j octanoic acid moiety is attached at the starred amino 



