Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1985-1-31
pubmed:abstractText
Pulsed positive and negative ion methane chemical ionization mass spectrometry of pyrrolizidine alkaloids is reported. Positive ion spectra are characterized by a high relative abundance of [MH]+ ions while the negative ion spectra exhibit ion peaks due to dissociative electron capture. Fragmentation in both positive and negative ion spectra primarily occurs at the ester groups with the positive charge residing with the pyrrolizidine ring system while the negative charge in contrast tends to reside with the necic acid moiety. Esterification at C-9 v. C-7 can be distinguished for non-cyclic esters of retronecine in the positive ion spectra.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0306-042X
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
455-61
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Positive and electron capture negative ion methane chemical ionization mass spectrometry of pyrrolizidine alkaloids.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.