| Title:  Circulins Literature References:  Polypeptide antibiotics related to polymyxins.  Produced by Bacillus circulans, a microorganism found in soil and dust:  Murray, Tetrault, Proc. Soc. Am. Bact. 1, 20 (1948); McLeod, J. Bacteriol. 56, 749 (1948); Murray et al., ibid. 57, 305 (1949).  Isoln yields circulins A and B, circulin A being the major component:  Tetrault, US 2676133 (1954 to Purdue Res. Found.).  Review: Vogner, Studer, Experientia 22, 345 (1966).   Derivative Type:  Circulin A  Molecular Formula:  C53H100N16O13 Molecular Weight:  1169.46 Percent Composition:  C 54.43%, H 8.62%, N 19.16%, O 17.79% Literature References:  Structure:  Fujikawa et al., Experientia 21, 307 (1965).  Synthesis:  Studer et al., Helv. Chim. Acta 49, 974 (1966).   Derivative Type:  Sulfate  Molecular Formula:  C53H100N16O13.2½H2SO4 Molecular Weight:  1414.66 Percent Composition:  C 45.00%, H 7.48%, N 15.84%, O 26.01%, S 5.67% Properties:  Crystals or amorphous solid, dec 226-228°.  [a]D25 -61.6° (c = 1.25).  Sol in water; less sol in the lower alcs.  Practically insol in acetone and water-immiscible solvents. Optical Rotation:  [a]D25 -61.6° (c = 1.25)   Derivative Type:  Circulin B  Molecular Formula:  C52H98N16O13 Molecular Weight:  1155.43 Percent Composition:  C 54.05%, H 8.55%, N 19.40%, O 18.00% Literature References:  Structure:  Hayashi et al., Experientia 24, 656 (1968).   |