Clément Delaude

Acylated triterpene saponins from the roots of Securidaca longepedunculata

Four triterpene saponins, 3-O-beta-D-glucopyranosylpresenegenin 28-O-beta-D-apiofuranosyl-(1-->3)-beta-d-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, 3-O-beta-D-glucopyranosylpresenegenin 28-O-beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-[(6-O-acetyl)-beta-D-glucopyranosyl-(1-->3)]-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, 3-O-beta-D-glucopyranosylpresenegenin 28-O-beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, and 3-O-beta-D-glucopyranosylpresenegenin 28-O-beta-D-apiofuranosyl-(1-->3)-[alpha-L-arabinopyranosyl-(1-->4)]-beta-D-xylopyranosyl-(1-->4)-[beta-D-apiofuranosyl-(1-->3)]-alpha-L-rhamnopyranosyl-(1-->2)-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-beta-D-fucopyranosyl ester, were isolated from the roots of Securidaca longepedunculata, together with three known compounds. Their structures were established mainly by 2D NMR techniques and mass spectrometry.

Saponins from Steganotaenia araliacea.

Six saponins have been isolated and identified from the leaves of Steganotaenia araliacea. They were identified as 3-O-[beta-D-galactopyranosyl(1----2)-(beta-D-galactopyranosyl (1----3))-beta-D-glucuronopyranosyl]-21-O-tigloyl and -21-O-angeloyl-R1-barrigenol, 3-O-[beta-D-glucopyranosyl(1----2)-(beta-D-xylopyranosyl (1----3))-beta-D-glucuronopyranosyl]-21-O-tigloyl and -21-O-angeloyl-R1-barrigenol, 3-O-[beta-D-glucopyranosyl(1----2)-(beta-D-glucopyranosyl-(1----3))-(alp ha-L- rhamnopyranosyl(1----4))-beta-D-glucopyranosyl] steganogenin and 3-O-[(beta-D-galactopyranosyl(1----2)-beta-D-glucuronopyranosyl]-2 8-O- beta-D-glucopyranosyl olean-12-ene-28-oic acid. Steganogenin is a new 17,22-seco-oleanolic acid derivative. The structures of the saponins were established by analysis of their 1H and 13C NMR spectra with the help of 2D-experiments and by Californium Plasma Desorption Mass Spectrometry.

Further alkaloids from strychnos longicaudata and strychnos ngouniensis

Abstract Twenty four alkaloids have been isolated and identified from the root and stem barks of Strychnos longicaudata Gilg and Strychnos ngouniensis Pellegrin. Among these, 17 alkaloids are isolated for the first time; the novel bisindole series represented by longicaudatine includes now two other compounds: longicaudatines F and Y; besides ngouniensine, its epimer epingouniensine has been isolated along with two glucosyl-ngouniensines. Other new alkaloids include tubotaiwinal and several bases possessing the akuammicine skeleton.

Alkaloids of Strychnos johnsonii

Abstract Twenty-three alkaloids have been identified in the root bark and stem bark of Strychnos johnsonii from Zaire. They are demethoxycarbonyl-3,14-dihydro-gambirtannine, angustine, dihydro-cycloakagerine, O -ethylakagerine, O -ethylakagerine lactone, dihydro decussine, normalindine, oxojanussine, tetrahydroalstonial, ajmalicinial, norepimalindine, norharman, harman, akagerine, akagerine lactone, janussines A and B, tetrahydro akagerine, demethoxycarbonyl-3,14,15,16,17,18-hexahydro-gambirtannine, dihydrocorynantheol, anthirine lactone, anthirine and isoanthirine.

Saponins from Harpullia cupanioides

Five new saponins have been isolated from the stem bark of Harpullia cupanioides and identified as 3-O-beta-D-glucopyranosyl(1-->2)[alpha-L-rhamnopyranosyl(1-->3)] beta-D-glucuronopyranosyl 22-O-angeloyl-A1-barrigenol, 3-O-beta-D-glucopyranosyl(1-->2)[alpha-L-rhamnopyranosyl(1-->3)] beta-D-glucuronopyranosyl 28-O-angeloyl-A1-barrigenol, 3-O-beta-D-galactopyranosyl(1-->2)[alpha-L-rhamnopyranosyl(1-->3)] beta-D-glucuronopyranosyl 28-O-angeloyl-A1-barrigenol. 3-O-beta-D-galactopyranosyl(1-->2)[alpha-L-rhamnopyranosyl(1-->3)] beta-D-glucuronopyranosyl 16-O-beta, beta-dimethylacryloyl-camelliagenin A and 3-O-beta-D-glucopyranosyl(1-->2)[alpha-L-rhamnopyranosyl(1-->3)] beta-D-glucuronopyranosyl 28-O-angeloyl-camelliagenin A. The structures were elucidated by analysis of 2D-NMR spectra and mass spectra.

Alkaloids from Alstonia congensis

Abstract Fifteen alkaloids were found in the root bark, stem bark and leaves of Alstonia congensis. They are echitamidine, echitamine, nor-echitamine, 17-acetoxy-nor-echitamine, akuammicine, 12-methoxyakuammicine, 12-methoxy-N(4)-methylakuammicine, tubotaiwine, 12-methoxytubotaiwine, angustilobines A and B, 6,7-seco angustilo-bines A and B, angustilobine B-N(4)-oxide and akuammidine.

β-Carboline glucoalkaloids from Strychnos mellodora

Abstract Two new N b -methylated β -carbolinium glucoalkaloids, 3,4,5,6-tetradehydropalicoside and 3,4,5,6-tetradehydrodolichantoside, together with the known β -carboline compounds desoxycordifoline (β-carboline 3-carboxylate glucoalkaloid) and melinonine F ( N b -methylated harmanium cation), were isolated from Strychnos mellodora stembark. The structures of the compounds were elucidated on the basis of spectroscopic studies.

Alkaloids from roots of Strychnos potatorum

Twenty-four compounds have been isolated and identified in the root bark of Strychnos potatorum. They are: Harmane carboxamide, cantleyine, 18,19-dihydrousambarensine, polyneuridine, norharmane, akuammidine, nor-C-flurorocurarine, ochrolifuanine A, bisnordihydrotoxiferine, ochrolifuanine E, normacusine B, normavacurine, henningsamine, 11-methoxyhenningsamine, dihydrolongicaudatine, dihydrolongicaudatine Y, antirhine, (20R- and (20S-dihydroantirhine, 11-methoxy-12-hydroxydiaboline, diaboline, 11-methoxydiaboline, desacetylretuline and diaboline N-oxide. The alkaloids in italic are novel.

Alkaloids from roots of Strychnos matopensis

Abstract Twenty-six alkaloids have been identified in the root bark of Strychnos matopensis from Zaire. They are Wieland-Gumlich aldehyde (WGA), desoxy WGA, N -formyldesoxy WGA, nor - C -fluorocurarine, N -desacetylretuline, N -desacetylisoretuline, isorosibiline, (16R)-isositsirikine, 1 1-methoxy diaboline, diaboline, matopensine, 16-methoxy isomatopensine, 16-ethoxy isomatopensine, 18-hydroxy matopensine, 18,18′- bis -hydroxy matopensine, matopensine N -oxide, strychnofuranine, bisnordihydrotoxiferine, bisnor-C-alkaloid H, bisnor-C-curarine, bisnor-C-alkaloid D, longicaudatine, longicaudatine F, longicaudatine Y, longicaudatine Z and N -oxylongicaudatine. The new compounds are N -formyldesoxy-Wieland-Gumlich aldehyde, the derivatives of matopensine, strychnofuranine and longicaudatine Z. Strychnofuranine is made up of two geissoschizal units with C-16 and C-17 being condensed into a furan ring.

Alkaloids of Pterotaberna inconspicua

Abstract Sixteen alkaloids were isolated from the seeds and root-bark of Pterotaberna inconspicua , collected in Zaire. They were voacangine 3-carbonitrile, voacangine, voacristine, 3,6-oxido-voacangine, vobasine, 10-hydroxycoronaridine, 10-hydroxyheyneanine, methuenine, apparicine, tubotaiwine, 16-epi-isositsirikine, 16-epimethuenine, 3,14-dihydroellipticine, an isomer of corynantheol, 16-epimethuenine N -oxide and tetra-hydroellipticine.