On methylation with dimethyl sulfate and sodium hydroxide, d-usnic acid afforded
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چکیده
give faint yellow crystals, m.p. 235°. It was soluble in NaHCO3 solution and gave brown coloration with FeCl3. Anal. Found: C, 66.76, 66.37; H, 5.44, 5.37. Acetylation of (I)-A mixture of 10g. of (I), 100cc. of Ac2O and 20 drops of conc. H2SO4 was warmed on a water bath for 3hr. and after cooling, the mixture was poured into ice water. Brown precipitates that separated out were treated with MeOH and then recrystallized from a mixture of EtOH and benzene to yellow crystals, m.p. 172~173° (V). Yield, 4g. It was optically inactive and
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