Bisbenzylisoquinoline Alkaloids

API-ionspray MS and MS/MS study on the structural characterization of bisbenzylisoquinoline alkaloids

“…In the Q1 scan MS data, all of alkaloids revealed apparent protonated molecular or molecular (thalistyline, semiquaternary) ions, together with very intense doublyprotonated molecular ions (base peak), which were not observed for those in the EI-MS, CI-MS [4][5][6][7][15][16][17][18][19][20][21] and FAB-MS [13,14]. In the API-ionspray MS/MS, the bond-cleavages between both benzylic ring E and ring AB, and ring F and ring CD formed abundant ethereal diisoquinoline ions for the most of investigated alkaloids, such as ions a and b via obamegine, thalrugosine, and homoaromoline, ions c and d via isotetrandrine, oxyacathine, and obaberine, ions I and j via thalicberine and O-methylthalicberine, ions l and m via thalrugosidine, ions n and o via thalidasine, ions p and q via thalmirabine, ions r and s via hernandezine, thalrugosaminine, and thalibrunine, and ion u via thalsimine (Fig.…”

“…Biological activities of the 20 bisbenzylisoquinoline alkaloids have been investigated previously [1][2][3][4][5][15][16][17][18][19][20][21]. Among them, thalugosine, thalugosidine, thalrugosaminine, thalidezine, thalistyline, hernandezine and O-methyl thalicberine exhibited antimicrobial activity against Mycobacterium smegmatis [3,4,[15][16][17][18], and obamegine, isotetrandrine, thalrugosaminine, thalidasine and thalistyline showed hypotensive activity in the dog and rabbit [4,[16][17][18].…”

“…Bisbenzylisoquinoline alkaloids exert hypotensive, antimicrobial, analgesic, muscle relaxant, and antitumor activities [1][2][3][4][5]. Obamegine, thalrugosine, thalrugosidine, and thalistyline of the 20 investigated alkaloids exhibit antimicrobial and hypotensive activity [1][2][3][4][5].…”

“…Bisbenzylisoquinoline alkaloids exert hypotensive, antimicrobial, analgesic, muscle relaxant, and antitumor activities [1][2][3][4][5]. Obamegine, thalrugosine, thalrugosidine, and thalistyline of the 20 investigated alkaloids exhibit antimicrobial and hypotensive activity [1][2][3][4][5]. Previously, structural elucidation of these natural products have mainly relied on EI-MS, CI-MS and FAB-MS, however, these techniques are not sensitive, and need more than 10 g of material [4,[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22].…”

“…Previously, structural elucidation of these natural products have mainly relied on EI-MS, CI-MS and FAB-MS, however, these techniques are not sensitive, and need more than 10 g of material [4,[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. Early EI-MS and FAB-MS studies displayed low abundances of molecular/adduct molecular ions and fragment ions for these alkaloids [4,[6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. CI-MS showed intense protonated molecular ions for these secondary and tertiary alkaloids with very less fragment ions for the structural information of the secondary and tertiary alkaloids, and no molecular ions detected for the quaternary alkaloids [4,[6][7][8][9][10][11][12][13][14]…”