Phytochemical and Pharmacological Investigation of the Cardioactive Constituents of the Leaf of Dysoxylum lenticellare

Abstract

The cardiac effects of the leaf extract and 11 isolated pure compounds have been examined on isolated, spontaneously beating, atrial muscles of the rat. Using nor-adrenaline (8 X 10(-7)M) and acetylcholine (4 X 10(-8)M) as reference drugs and normal saline (equivalent volume) as control, the crude extract of Dysoxylum lenticellare (8 X 10(-4) g/ml) induced negative chronotropic and positive inotropic responses on the isolated cardiac muscle preparations. The extract demonstrated significant (p less than 0.05-0.01) cardioactivity as attested to by its positive inotropic and/or negative chronotropic activities on the rat atrial preparations. Of the pure isolates tested, 7, 8, and 9 demonstrated significant cardiac effects. Although the precise mechanism of action of the extract or pure isolates on the atrial myocardium has not been fully determined, available experimental data suggest that the extract and pure isolates act directly on the cardiac muscle. Alkaloids 7, 8, and 9 manifest cardiac effects similar to that of the crude extract but of lesser magnitude. Some indirect effects of these isolates may, however, be associated with the manifested activities.

Asymmetric synthesis of tetrahydroisoquinolines by enzymatic Pictet–Spengler reaction

“…22,23) In an earlier work, Battersby et al suggested that the synthetic pathway of these compounds involves condensation between dopamine and cinnamaldehyde 24) ; however, cinnamaldehyde was not found to be accepted by CjNCS. 20) In this report, we demonstrated that CjNCS can synthesize 1-phenethyl tetrahydroisoquinoline from dopamine and hydrocinnamaldehyde.…”

Reviewing Colchicaceae Alkaloids – Perspectives of Evolution on Medicinal Chemistry

“…There are only few reports of isolation of these alkaloids [74, 75, 76, 77, 78], perhaps due to their proposed functions as precursors and thus efficient transformation into other structural types. They do not seem to have been tested for biological activity, but phenethylisoquinolines from Dysoxylum have shown effects on isolated rat cardiac muscle [79]. …”

Sesquiterpenes fromDysoxylum oliganthumandDysoxylum excelsum

“…A number of structural types of compounds, including triterpenoids [2,3], alkaloids [4], diterpenoids [5], and limonoids [6], were isolated from this genus. Some of the isolates showed biological activities, such as antibacterial triterpenoids [2], antitumor triterpenoid saponins [3], cardiac active alkaloids [4], cytotoxic diterpenoids [5], and anti-RSV and antifeeding tetranortriterpenoids [6]. However, the chemical constituents of Dysoxylum oliganthum and D. excelsum have not been investigated previously.…”