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1.
Nat Prod Res ; 27(3): 282-5, 2013.
Article in English | MEDLINE | ID: mdl-22404642

ABSTRACT

Chemical investigation of the aerial part and the roots of Euphorbia hyberna L. subs. hyberna. resulted in the isolation and identification of four triterpenoids (3ß-O-octadecanoyllupeol (1), glut-5-en-3ß-ol (2), 24-methylenecicloartan-3ß-ol (3) and cicloart-23-ene-3ß,25-diol (6)) along with the phenolic compounds ellagic acid (4) and 3,3'-di-O-methylellagic acid (7). Although these are all known compounds, this is the first report of their isolation from this plant. Their structures were elucidated on the basis of spectral methods, including 2D NMR experiences, and confirmed by comparing with the literature data.


Subject(s)
Euphorbia/chemistry , Ellagic Acid/analogs & derivatives , Ellagic Acid/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Roots/chemistry
3.
Rapid Commun Mass Spectrom ; 18(24): 2969-75, 2004.
Article in English | MEDLINE | ID: mdl-15536633

ABSTRACT

Several 2H-chromenes derived from carbazoles were analyzed by electrospray tandem mass spectrometry. The 2H-chromenes constitute an important class of compounds that exhibit photochromic activity. The fragmentation pathways of the protonated molecular species [M+H]+ were studied, and main fragmentation pathways of these compounds were identified. Fragmentation pathways of [M+D]+ ions were also studied in order to obtain information about the location of the ionizing proton or deuteron. It was found that the proton is not preferentially located on the nitrogen atom. The charge is preferentially located as a tertiary carbocation, resulting from the uptake of the proton (or deuteron) by the zwitterionic open structure of the chromenes. The major fragmentation occurred by cleavage of the gamma-bond relative to the carbocation center, leading to a fragment at m/z 191 (C5H11+ or C14H9N+), which are the most abundant fragment ions for almost all compounds. The presence of substituents in the chromene ring does not change this behavior. Other observed common fragmentation pathways included loss of CH3* (15 Da), loss of CO (28 Da), combined loss of CO and CH3 (43 Da), and loss of the phenyl ring via combined loss of C6H4 and CH3* (-91 Da) and combined loss of C6H6 and CO (-106 Da).

4.
Phytochemistry ; 61(4): 373-7, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12377228

ABSTRACT

A new diterpene tetraester, from the jatrophane family, and two new diterpene triesters, with a lathyrane skeleton, have been isolated from the chloroform extract of the roots of Euphorbia hyberna L. The structures of these compounds have been established by spectroscopic methods, including 2D NMR experiments.


Subject(s)
Diterpenes/chemistry , Diterpenes/isolation & purification , Euphorbia/chemistry , Plant Extracts/chemistry , Plant Roots/chemistry
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