Oblongine — A new quaternary alkaloid from Berberis oblonga

Constituents of West African Medicinal Plants XXV. Isolation of Oblongine from Tiliacora dinklagei and the Synthesis of Oblongine and Related Benzylisoquinoline Alkaloids

“…Crystallization from methanol-acetone (1:1) gave needles of oblongine iodide ( 17 2910, 1600, 1510, 1470, and 1450 cm '; ms, M+ mlz 314 (10%) consistent with Cl9H24N03, with other fragment ions at mlz 313 (M+-l) (44), 192(100), 177 (10), 142 (13), 128(46), 127(38) and 58(32); pmr (see table 1). These data were in good agreement with those published for oblongine (17) (6,8). Synthesis of 7,s-dimethoxy-2-methyl-i,2,3,4-tetrahydroisoquinoline (3).-This compound was synthesized using the general method described by Bobbitt etal.…”

“…Chromatography of the crude alkaloid iodide fraction over a column of acid alumina afforded a fraction containing oblongine (17). Re-chromatography of the oblongine-containing fraction over a column of silica gel G afforded pure oblogine (17), which was identified by comparison of its physical properties with published values (6).…”

“…Prior to the initiation of this study, oblongine (17) had been isolated only once from a natural source, Berberís oblonga (Berberidaceae) (6). In addition to its occurrence in T. dinklagei, it has subsequently been found in T. funifera (7) and B. baluchistanica (8).…”

“…In anticipation of their isolation, we wish to present here their physical properties for future reference. Selected properties of certain other related compounds (6)(7)(8)(9)(10)14) obtained in the course of the Jn synthesis but not new, are also reported for the purpose of completeness and comparison.…”

Pharmacological evaluation of natural product analogues. I. Preliminary pharmacological evaluation of O‐methylgortschakoine and O‐methylpetaline

“…On the contrary, 7,8-substitution has been shown to occur only in a few tetrahydrobenzylisoquinolines, from a number of species belonging to Berberidaceae , Menispermaceae and Rhamnaceae (McCorkindale et al, 1964(McCorkindale et al, , 1969Grethe et al, 1970;Karimov et al, 1976;Irgashev et al, 1977;Ziyaev et al, 1977;Tackie et al, 1980;Abu Zarga et al, 1981;Dwuma-Badu et al, 1983). Examples are, the tertiary alkalids juziphine I1 (Grethe et al, 1970;Ziyaev et af., 1977) and gortschakoine 111 and the quaternary alkalids oblongine IV (Karimov et al, 1976;Tackie et af., 1980;Abu Zarga et al, 1981) and petaline V (McCorkindale et al, 1964(McCorkindale et al, , 1969Dwuma-Badu et al, 1983). Although, the pharmacological effects of the 6,7-disubstituted benzylisoquinoline alkaloids have been extensively investigated, nothing has been reported concerning the effects of the 7,8-type of substituted compounds.…”