7718. Precocenes

Nomenclature

Anti-JH.

Description and references

Anti-juvenile hormones found in plants that induce reversible precocious metamorphosis and sterilization in insects by suppressing the function of the corpora allata gland: W. S. Bowers et al., Science 193, 542 (1976); W. S. Bowers, R. Martinez-Pardo, ibid. 197, 1369 (1977). Isoln from Ageratum mexicanum Sw., Compositae and structure: A. R. Alertsen, Acta Chem. Scand. 9, 1725 (1955). Synthesis of precocene I: R. Livingstone, R. B. Watson, J. Chem. Soc. 1957, 1509; of precocene II: R. Huls, Bull. Soc. Chim. Belg. 66, 409 (1957); 67, 22 (1958); of I and II: J. R. Hlubucek et al., Aust. J. Chem. 24, 2347 (1971); A. Banerji, N. C. Goomer, Indian J. Chem. 20B, 144 (1981); V. K. Ahluwalia et al., Chem. Ind. (London) 1982, 369. Biosynthesis: A. V. Vyas, N. B. Mulchandani, Phytochemistry 19, 2597 (1980). Metabolism studies: D. M. Soderlund et al., J. Agric. Food Chem. 1980, 724; B. J. Bergot et al., Pestic. Biochem. Physiol. 13, 95 (1980). Mechanism of action: W. S. Bowers, Am. Zool. 21, 737 (1981).

Chemical structure

Derivative

Precocene I.

Nomenclature

7-Methoxy-2,2-dimethyl-2H-1-benzopyran; 7-methoxy-2,2-dimethylchromene; 6-demethoxyageratochromene.
C12H14O2; mol wt 190.24.
C 75.76%, H 7.42%, O 16.82%.

Properties

Oil, bp6 120°. nD21 1.5548. uv max (ethanol): 280, 304 nm (ε 6644, 5844).

Derivative

Precocene II.

Nomenclature

6,7-Dimethoxy-2,2-dimethyl-2H-1-benzopyran; 6,7-dimethoxy-2,2-dimethylchromene; ageratochromene.
C13H16O3; mol wt 220.26.
C 70.89%, H 7.32%, O 21.79%.

Properties

Crystals, mp 47.5°, bp6 136°. uv max (ethanol): 280, 323 nm (ε 5500, 9200).