CRYSTAL AND MOLECULAR STRUCTURE OF THE GUAIANOLIDE GADLLARDIN

摘要

Continuing an investigation of an extract of the epigeal part of fleabane mullet Pulicaria uliginosa [1], we have isolated from the chloroform extract a crystalline substance Ci7H22O5, mp 188-19O°C [oiD ±0°(c 0.5, chloroform). According to its IR spectrum (3520, 1770, 1735, 1680 cm"1) the substance was an acylated -y-lactone. It contained acetyl and hydroxy groups, as was confirmed by mass spectroscopy and PMR. The mass spectrum showed peaks of ions with m/z 306 (M+), 288 (M+ - H2O) and 247 (M+ - OCOCH3). The substance was not acetylated by acetic anhydride in pyridine with heating, which showed the tertiary characterof its hydroxy group.