Characterisation and determination of indole alkaloids in frog‐skin secretions by electrospray ionisation ion trap mass spectrometry

Abstract

The characterisation of selected indole alkaloids in a quadrupole ion trap mass spectrometer is presented. Fragmentation profiles for tryptamine, 5-hydroxytryptamine (5-HT), N'-methyl 5-hydroxytryptamine (N'-methyl 5-HT), N',N'-dimethyl 5-hydroxytryptamine (bufotenine), N',N',N'-trimethyl 5-hydroxytryptamine (5-HTQ), and N',N'-dimethyl 5-methoxytryptamine (5-MeODMT) are presented with proposed structures given for each product ion observed. Such MS(n) experiments can be used to differentiate the isobaric molecular ions of the compounds 5-HTQ (M(+)) and 5-MeODMT (MH(+)). The quantitative determination of certain indole alkaloids in the skin secretions of the Australian Golden Bell frog, Litoria aurea, by LC/ESI-ion trap MS is also presented. The concentrations of 5-HT, N'-methyl 5-HT and 5-HTQ were found to be 2.68, 0.26 and 0.54 microg per mg of skin secretion, respectively.

Therapeutic potential of antisense oligodeoxynucleotides to down-regulate thymidylate synthase in mesothelioma

“…The literature is replete with reports that mesothelioma cells have developed multiple strategies to avoid apoptosis as well as antisense targeting of elements of antiapoptotic pathways, including transforming growth factor-h2 (34), inhibitor of apoptosis protein-1 (35), survivin (36), and Bcl-x L (37,38), have been reported to enhance apoptosis in mesothelioma cell lines. However, antisense targeting has not been shown previously to target mesothelioma cells preferentially, nor has it been shown that antisense targeting of a mRNA directing production of a protein only indirectly involved in apoptosis results in death of mesothelioma cells but not of nonmalignant mesothelioma cells.…”

Electrospray ionization-ion trap mass spectrometry study of PQAAPro and PQProAA mimetic derivatives of the antimalarial primaquine

“…This technique has provided deeper insight into the structural properties and stability of numerous compounds, from natural products [1-3] to synthetic drugs [4-8], peptides [9-23], and heterocycles [24][25][26][27][28], among many others. Notwithstanding, little has been done on the application of this technique to the study of relevant antimalarials such as primaquine (PQ, 1) or related structures.…”

“…Overall, this work embodies an original and valuable contribution towards a deeper insight into the molecular properties of novel antimalarials, which can be viewed as representative of both the O ver the past decade, electrospray ionization mass spectrometry (ESI-MS) has been used for the most diverse analytical purposes. This technique has provided deeper insight into the structural properties and stability of numerous compounds, from natural products [1][2][3] to synthetic drugs [4][5][6][7][8], peptides [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], and heterocycles [24][25][26][27][28], among many others. Notwithstanding, little has been done on the application of this technique to the study of relevant antimalarials such as primaquine (PQ, 1) or related structures.…”

Quality Evaluation of Traditional Chinese Drug Toad Venom from Different Origins through a Simultaneous Determination of Bufogenins and Indole Alkaloids by HPLC

“…13) The presence of abundant indole-alkylamines in the drug was ignored in previous studies, which could affect the safety of the drug. 14) This oversight could seriously affect the quality control and clinical utilization of toad venom.…”

“…The structures of these compounds were identified by determining 1 H-, 13 C-NMR and mass spectra, and by comparing their spectral data with the literature values. They are serotonin (1), 14) NЈ-methyl serotonin (2), 14) bufotenine (3), 9) bufotenidine (4), 14) bufotenine oxide (4), 15) bufobutanoic acid (4؆), 9) gamabufotalin (5), 18) arenobufagin (6), 16) hellebrigenin (7), 17) desacetylcinobufotalin (7), 17) bufotalin (8), 17) telocinobufagin (9), 18) cinobufotalin (10), 18) bufalin (11), 17) resibufogenin (12), 17) cinobufagin (13) Table 1). The voucher specimens were deposited in the Pharmacognosy Department, Shenyang Pharmaceutical University (Shenyang, China).…”