CAS Registry Number: 544-51-4
CAS Name: 3,5,7,8-Tridecatetraene-10,12-diynoic acid
Molecular Formula: C13H10O2
Molecular Weight: 198.22
Percent Composition: C 78.77%, H 5.08%, O 16.14%
Line Formula: HCºC-CºCCH=C=CHCH=CHCH=CHCH2COOH
Literature References: Antibiotic substance produced by Nocardia acidophilus: Johnson, Burdon, J. Bacteriol. 54, 281 (1947); Johnson, Soc. Am. Bacteriologists, 49th General Meeting (May, 1949), Abstracts of Papers, p 68; Celmer, Solomons, 121st A.C.S. Meeting (Milwaukee, 1952), Abstracts of Papers, p 17-J; J. Am. Chem. Soc. 74, 1870, 2245 (1952); 75, 1372 (1953). Synthesis: Bohlmann, Sucrow, Angew. Chem. 76, 611 (1964).
Properties: Needles from methylene chloride at -40°. Very thermolabile. Complete retention of activity is possible only by storage at -40° or lower. mp 7.5° (deflagrates). [a]D25 -130° (c = 0.4 in ethanol). uv max (ether): 267, 281 nm (e 61,000, 67,000). Sol in alcohol, ether, amyl acetate, methylene chloride. Forms a water-sol sodium salt. The acid itself is sparingly sol in water and is relatively stable in extremely dil aq solns (approx 0.005 mg/ml), half-life inversely related to concn. Undergoes an unusual rearrangement in normal aq KOH at 27°, involving an allene to acetylene isomerization accompanied by migration of the existing acetylenic bonds. The rearranged acid, isomycomycin, has been assigned the structure 3,5-tridecadiene-7,9,11-triynoic acid, CH3-CºC-CºC-CºC-CH=CHCH=CHCH2COOH.
Melting point: mp 7.5° (deflagrates)
Optical Rotation: [a]D25 -130° (c = 0.4 in ethanol)
Absorption maximum: uv max (ether): 267, 281 nm (e 61,000, 67,000)