| Title:  Picrolichenic Acid CAS Registry Number:  466-34-2 CAS Name:  6-Hydroxy-2¢-methoxy-2,4¢-dioxo-4,6¢-dipentylspiro[benzofuran-3(2H),1¢-[2,5]cyclohexadiene]-5-carboxylic acid Additional Names:  picrolichenin Molecular Formula:  C25H30O7 Molecular Weight:  442.50 Percent Composition:  C 67.86%, H 6.83%, O 25.31% Literature References:  Bitter acidic principle of crustose lichen, Pertusaria amara (Ach.) Nyl., Pertusariaceae.  Isoln:  Alms, Ann. Pharm. 1, 61 (1832).  Identity of picrolichenin and picrolichenic acid:  Zopf, Ann. 321, 38 (1902).  Isoln and structure:  Wachmeister, Acta Chem. Scand. 12, 147 (1958).  Synthesis:  Davidson, Scott, J. Chem. Soc. 1961, 4075. Properties:  Prisms from benzene, dec 184-187°; prisms from aqueous acetic acid, decomp 187-190°.  Intense bitter taste similar to that of quinine.  Optically inactive.  uv max:  245, 270-277 nm (e 24,000, 7800).  Readily sol in most organic solvents except benzene and light petroleum. Absorption maximum:  uv max:  245, 270-277 nm (e 24,000, 7800)   Derivative Type:  Methyl picrolichenate  Molecular Formula:  C26H32O7 Molecular Weight:  456.53 Percent Composition:  C 68.40%, H 7.07%, O 24.53% Properties:  Needles from methanol, mp 102-103.5°.  Soluble in cold 0.5N NaOH. Melting point:  mp 102-103.5°   Derivative Type:  Methyl O-methylpicrolichenate  Molecular Formula:  C27H34O7 Molecular Weight:  470.55 Percent Composition:  C 68.92%, H 7.28%, O 23.80% Properties:  Needles from hexane, mp 80-82°.  Practically insol in cold 0.1N NaOH. Melting point:  mp 80-82°     Status:  This monograph has been retired and is no longer subject to revision or update.  |