7382. Physodic Acid

Nomenclature

CAS number: 84-24-2
3,8-Dihydroxy-11-oxo-1-(2-oxoheptyl)-6-pentyl-11H-dibenzo[b,e][1,4]dioxepin-7-carboxylic acid; 4,4′,6′-trihydroxy-6-(2-oxoheptyl)-2′-pentyl-2,3′-oxydibenzoic acid-ε-lactone; physodalin.
C26H30O8; mol wt 470.51.
C 66.37%, H 6.43%, O 27.20%.

Description and references

From the lichens Parmelia physodes (L.) Ach.: Hesse, Ber. 30, 1983 (1897); Klosa, Pharm. Ind. 15, 46 (1953); and Cetraria ciliaris Ach.: Culberson, Science 143, 255 (1964). Structure: Asahina, Nogami, Ber. 67, 805 (1934); 68, 77 (1935).

Chemical structure

Properties

Needles from methanol, mp 205°. uv max (95% ethanol): 256 nm (log ε 4.2). Sol in ether, acetone, hot methanol; somewhat sol in cold ethanol, methanol, hot chloroform; practically insol in benzene, petr ether, carbon disulfide.

Derivative

Diacetate.
C30H34O10; mol wt 554.58.
C 64.97%, H 6.18%, O 28.85%.

Properties

Plates from acetone + carbon disulfide, mp 153-155.5°.

Derivative

Methyl ester.
C27H32O8; mol wt 484.54.
C 66.93%, H 6.66%, O 26.42%.

Properties

Prisms from 80% alcohol, mp 156-157°.