Field‐Desorption Mass Spectra of Fern Phloroglucinols Containing Three to Six Ring Constituents

Abstract

It has been previously shown that the structural analysis of the title compounds by electron-impact ionization (EI) mass spectrometry is complicated by extensive, If not complete, thermal rottlerone-type rearrangement and/or fragmentation reactions. The use of a 'softer' ionization technique such as field desorption (FD) is, therefore, required in order that these compounds may be characterized in terms of their molecular size and composition. In this report, the FD mass spectra of typical representatives of this class of compounds are described along with the attempted suppression of undesirable thermal reactions by the optimization of the emitter temperatures.

Families with Species of Questionable Toxicity or Significance

“…In sheep, a disease suspected to be caused by consumption of Cistus for several weeks appeared to be mainly neurologic with episodes of tremor lasting 2 -3 minutes followed by hypersensitivity resulting in seizures (Ligios Although disease problems caused by Halimium have not been reported in North America, a neurologic disease in sheep over 3 years of age grazing H. brasiliense during the late summer and early fall on a number of farms in Brazil and Uruguay has been described (Riet -Correa et al 2009). The disease, characterized by transient seizures stimulated by disturbing the animals, is associated with long-term grazing or experimentally feeding for 30 -100+ days.…”

“…In addition to the morphological features of the family, the genus exhibits thick, erect or short creeping rhizomes from which clusters of usually evergreen, semileathery fronds typically arise. Interestingly, affected Toxicity and anthelmintic activity appear to be due primarily to phloroglucinol derivatives or a mixture of acylphloroglucinols, which is referred to as crude fi licin (Widen et al 1980;Richter et al 1987;Murakami and Tanaka 1988). Habitats occupied by species of Dryopteris include moist or swampy woods, thickets, stream banks, shaded cliffs, and talus slopes.…”