Title: Ferrichromes
Literature References: Growth-promoting iron chelates. Ferrichrome and ferrichrome A first isolated from the rust fungus, Ustilago sphaerogena: Neilands, J. Am. Chem. Soc. 74, 4846 (1952); Garibaldi, Neilands, ibid. 77, 2429 (1955). Ferrichrome and four related compounds, ferrichrysin, ferricrocin, ferrirubin and ferrirhodin have also been isolated from Aspergillaceae and from Penicillium resticulosum: Zähner et al., Arch. Mikrobiol. 45, 119 (1963); Keller-Schierlein, Deer, Helv. Chim. Acta 46, 1907 (1963); Keller-Schierlein, ibid., 1920. Ferrichromes are cyclic hexapeptides containing three small, neutral amino acids and three derivatives of d-N-hydroxy-L-ornithine [HONH(CH2)3CH(NH2)COOH]. Structure: Rogers, Neilands, Biochemistry 3, 1850 (1964). Crystal and molecular structure of ferrichrome A: Zalkin et al., J. Am. Chem. Soc. 88, 1810 (1966). Synthesis of ferrichrome: Keller-Schierlein, Maurer, Helv. Chim. Acta 52, 603 (1969); Isowa et al., Bull. Chem. Soc. Jpn. 47, 215 (1974). Reviews of ferrichromes and other hydroxamic acids: Neilands, Struct. Bonding 1, 59-108 (1966); Emery, Adv. Enzymol. Relat. Areas Mol. Biol. 35, 135-185 (1971); J. B. Neilands, Bioinorg. Chem. II, K. N. Raymond, Ed. (A.C.S., Washington, 1977), pp 3-32.
Derivative Type: Ferrichrome
Molecular Formula: C27H42FeN9O12
Molecular Weight: 740.52
Percent Composition: C 43.79%, H 5.72%, Fe 7.54%, N 17.02%, O 25.93%
Properties: Long, yellow needles from anhydr methanol, shrink and blacken at 240-242° without melting. [a]D +300° (c = 0.04). Absorption max (methanol): 425 nm (E1%1cm 39.4). Sol in water and hot methanol; sparingly sol in ethanol, acetone, ether, chloroform.
Optical Rotation: [a]D +300° (c = 0.04)
Absorption maximum: Absorption max (methanol): 425 nm (E1%1cm 39.4)
Derivative Type: Ferrichrome A
Molecular Formula: C41H58FeN9O20
Molecular Weight: 1052.79
Percent Composition: C 46.77%, H 5.55%, Fe 5.30%, N 11.97%, O 30.39%
Properties: Crystals from water. Absorption max (0.1M phosphate buffer; pH 7): 440 nm (E1%1cm 33.8). Very sol in methanol, ethanol, propanol; slightly sol in hot water. Practically insol in acetone, petr ether, ether, chloroform.
Absorption maximum: Absorption max (0.1M phosphate buffer; pH 7): 440 nm (E1%1cm 33.8)
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