Vallesiachotamine and Isovallesiachotamine from the Seeds of Strychnos tricalysioides

Abstract

The alkaloids vallesiachotamine and isovallesiachotamine have been isolated from the seeds of Strychnos tricalysioides and identified on the basis of their spectral characteristics. The potential chemotaxonomic significance of these alkaloids is briefly discussed.

Phytochemical study and anti-inflammatory effect of Psychotria stenocalyx (Rubiaceae)

“…In the 1 H NMR spectra, the specific hydrogen chemical shifts of each isolated compound compared with the literature is coherent with the alkaloids strictosamide 3 (Atta-urRahman et al, 1991), pauridianthoside 4 (Levesque et al, 1977), vallesiachotamine lactone 5 (Passos et al, 2013a), Evallesiachotamine 6, and Z-vallesiachotamine 7 (Waterman et al, 1982). The structures of all compounds are shown in Fig. The compiled data on retention time, mass and UV spectra for all compounds are given in Table 1.…”

“…On the other hand, in the Z-isomer, the anisotropy of the aldehyde leads to a more deshielded 18-methyl group. Thus, a doublet at δ H18 2.10 ppm was observed for the E-isomer and at δ H18 2.20 ppm for the Z-isomer (Waterman et al, 1982). The 1:1 ratio of these E/Z isomers was calculated by the integration of these correspondent peaks in the HPLC chromatogram at λ max 290 nm.…”

Six New Triterpenoid Saponins from the Root and Stem Bark ofCephalanthus occidentalis

“…The known compounds were identified based on their spectroscopic data, and comparison with literature data, or with the authentic samples. These compounds include cincholic acid (7) [6], quinovic acid (8) [6], pyrocincholic acid (9) [13], glabratine (18) [14], strictosidine (19) [15], strictosamide (20) [16], vincosamide (21) [16], vallesiachotamine (22) [17], [18], isovallesiachotamine (23) [17], scopoletin (24) [19] [22], 7-epi-loganin (29) [22], loganin (30) [22], 8-epi-loganic acid (31) [22], 3-O-b-glucopyranosylsitosterol (32), arbutin (33), sucrose (34), and glucose (35). Glabratine (18) was previously isolated from the bark of Uncaria glabrata DC (Rubiaceae) [14].…”

“…deoxy-glucopyranosylcincholic acid 28-O-b-glucopyranosyl ester (13) [6], [11], 3-O-b-6-deoxyglucopyranosylquinovic acid 28-O-b-glucopyranosyl ester (14) [11], 3-O-b-glucopyranosylquinovic acid 28-O-b-glucopyranosyl ester (15) [8], 3-O-b-glucopyranosyl-(1®4)-a-rhamnopyranosylquinovic acid 28-O-b-glucopyranosyl ester (16) [12], 3-O-b-glucopyranosyl-(1®4)-b-fucopyranosylpyrocincholic acid 28-O-b-glucopyranosyl ester(17) …”

Vallesiachotamine

“…Since Dragendorff analyses indicated the presence of alkaloids in the crude extract of P. rigida, we reinvestigated this species to isolate and characterize these compounds. Fractionation using preparative thin-layer chromatography (TLC) on silica gel 60 of the alkaloidal fraction gave vallesiachotamine, (I), a minor bioactive constituent previously isolated from the Peruvian plant Vallesia dichotoma (Djerassi et al, 1966), the Asian shrub Rhazya orientalis (Evans et al, 1968) and the African plant Strychnos tricalysioides (Waterman & Zhong, 1982). It is noteworthy that bioautographic tests on TLC plates with Staphylococcus aureus, Micrococcus luteus and Bacillus subtillis displayed high antibacterial activity for the crude extract of P. rigida.…”