4419. Gibberellic Acid

Nomenclature

CAS number: 77-06-5
(1α,2β,4aα,4bβ,10β)-2,4a,7-Trihydroxy-1-methyl-8-methylenegibb-3-ene-1,10-dicarboxylic acid 1,4a-lactone; gibberellin X; gibberellin A3; Activol (Zeneca); Gibrel (AgriDyne).
C19H22O6; mol wt 346.37.
C 65.88%, H 6.40%, O 27.71%.

Description and references

Plant hormone; most outstanding of the plant-growth promoting metabolites of Gibberella fujikuroi. Isoln: P. J. Curtis, B. E. Cross, Chem. Ind. (London) 1954, 1066; B. E. Cross, J. Chem. Soc. 1954, 4670; P. W. Brian et al., US 2842051; C. T. Calam, P. J. Curtis, US 2950288; A. J. Birch et al., US 2977285 (1958, 1960, 1961, all to ICI). Stereochemistry and structure: G. Stork, H. Newman, J. Am. Chem. Soc. 81, 5518 (1959); B. E. Cross et al., Proc. Chem. Soc. London 1959, 302; F. McCapra et al., ibid. 1962, 185; D. C. Aldridge et al., J. Chem. Soc. 1963, 143; P. M. Bourn et al., ibid. 1963, 154. Partial synthesis: E. J. Corey et al., J. Am. Chem. Soc. 93, 7316 (1971). Stereospecific total synthesis: eidem, ibid. 100, 8034 (1978). Promotes growth of seedlings: M. J. Bukovac, S. H. Wittwer, Q. Bull. Mich. Agric. Exp. Stn. 39, 307 (1956); J. M. Merritt, J. Agric. Food Chem. 6, 184 (1958). Reviews: B. E. Cross et al. in Adv. Chem. Ser. 28, entitled “Gibberellins,” J. M. Merritt, Ed. (ACS, Washington DC, 1961) p 13; series of articles in Plant Growth Subst., Proc. 7th Int. Conf., D. J. Carr, Ed. (Springer-Verlag, Berlin, 1972).

Chemical structure

Properties

Crystals from ethyl acetate, mp 233-235° (effervescence). [α]D19 +86° (c = 2.12). pK 4.0. Slightly sol in water, ether. Freely sol in methanol, ethanol, acetone. Moderately sol in ethyl acetate. Sol in aq solns of sodium bicarbonate and sodium acetate.

Derivative

Methyl ester.
C20H24O6; mol wt 360.40.
C 66.65%, H 6.71%, O 26.64%.

Properties

Needles from benzene + methanol, mp 209-210°. [α]D20 +75° (c = 0.5).

Use

Plant growth regulator.