Title: Tunichrome B-1
CAS Registry Number: 97689-87-7
CAS Name: (aE)-3,5-Dihydroxy-L-tyrosyl-a,b-didehydro-3,5-dihydroxy-N-[(1Z)-2-(3,4,5-trihydroxyphenyl)ethenyl]tyrosinamide
Additional Names: TB-1
Molecular Formula: C26H25N3O11
Molecular Weight: 555.49
Percent Composition: C 56.22%, H 4.54%, N 7.56%, O 31.68%
Literature References: Major component of a group of polyphenolic yellow blood pigments isolated from the sea squirt (tunicate) Ascidia nigra (Linnaeus). The tunichromes are strong biological reducing agents involved in the selective accumulation of vanadium by A. nigra. Isoln of crude tunichrome mixture from the blood cells of A. nigra, action in converting vanadium(V) to vanadium(III): I. G. Macara et al., Biochem. J. 181, 457 (1979). Isoln of tunichrome B-1 by HPLC under anaerobic conditions, characterization and structure determn by mass spec, nmr: R. C. Bruening et al., J. Am. Chem. Soc. 107, 5298 (1985). Brief account of the role of tunichromes in studies into the biochemical nature of vanadium and other trace metals: R. J. Seltzer, Chem. Eng. News 63, 67 (Sept. 16, 1985). Review: R. C. Bruening et al., J. Nat. Prod. 49, 193 (1986).
Properties: Yellow solid, sol in methanol. uv max (methanol): 210, 340 nm (e 68000, 19600).
Absorption maximum: uv max (methanol): 210, 340 nm (e 68000, 19600)