Phytochemistry (v.66, #10)

Author Index (II).

Four tetranortriterpenoids from the stem bark of Khaya anthotheca by Michel K. Tchimene; Pierre Tane; Dieudonne Ngamga; Joseph D. Connolly; Louis J. Farrugia (1088-1093).
Four tetranortriterpenoids, 13 and 6R,8α-dihydroxycarapin, have been isolated from the stem bark of Khaya anthotheca.Eight limonoids, anthothecanolide (1), 3-O-acetylanthothecanolide (2), 2,3-di-O-acetylanthothecanolide (3), 6R,8α-dihydroxycarapin (4), 3β-acetoxy-3-deoxo-6R-hydroxycarapin (5), methyl angolensate, methyl 6-hydroxyangolensate and khayalactone together with sitosterol glucoside, have been isolated from the extracts of the stem bark of Khaya anthotheca. Compounds 14 are described for the first time. Their structures were established by analysis of the high-field NMR and MS data. The structure of compound 4 was confirmed by a single crystal X-ray structure analysis.
Keywords: Tetranortriterpenoids; Khaya anthotheca; Meliaceae; Anthothecanolide; 6,8-Dihydroxycarapin;

Sacculatane diterpenoids from axenic cultures of the liverwort Fossombronia wondraczekii by Hildegard Feld; Ursula Maria Hertewich; Josef Zapp; Hans Becker (1094-1099).
Five new sacculatane diterpenoids along with sacculatal and sacculatanolide have been isolated from axenic cultures of the liverwort Fossombronia wondraczekii and their structures assigned on the basis of their spectroscopical properties.Five new sacculatane diterpenoids, 17,18-epoxy-7-sacculaten-12,11-olide, 7,17-sacculatadien-11,12-olide, 11β,12-epoxy-7,17-sacculatadien-11α-ol, 1β-acetoxy-11β,12-epoxy-7,17-sacculatadien-11α-ol and 1β,15ξ-diacetoxy-11,12-epoxy-8(12),9(11),17-sacculatatriene along with sacculatal and sacculatanolide have been isolated from axenic cultures of the liverwort Fossombronia wondraczekii and their structures assigned on the basis of their spectroscopical properties.
Keywords: Fossombronia wondraczekii; Hepaticae; Sacculatanes; Axenic culture;

Mexicanolide limonoids from the Madagascan Meliaceae Quivisia papinae by Philip H. Coombes; Dulcie A. Mulholland; Milijaona Randrianarivelojosia (1100-1107).
The seeds of Quivisia papinae have yielded five mexicanolide group limonoids, together with two known mexicanolide limonoids and two known triterpenoids. Quivisianolide A 9 possesses a hitherto unreported 9α,11α-epoxide ring, quivisianolide B 10 the corresponding Δ9(11) double bond, and quivisianone 11 is a 17-keto seco-ring D compound.An investigation of the seeds of the Madagascan Meliaceae Quivisia papinae has yielded five mexicanolide group limonoids, together with two known mexicanolide limonoids and two known triterpenoids. Quivisianolide A 9 possesses a hitherto unreported 9α,11α-epoxide ring, quivisianolide B 10 the corresponding Δ9(11) double bond, and quivisianone 11 is a 17-keto seco-ring D compound.
Keywords: Quivisia papinae; Meliaceae; Madagascar; Seeds; Isolation; Mexicanolide limonoids; Melianol; Melianone; Swietenolide; Proceranolide; 2α-Hydroxyswietenolide; 7-Angeloyl-7-detigloylruageanin B; Quivisianolide A; Quivisianolide B; Quivisianone;

Plocoralides A–C, polyhalogenated monoterpenes from the marine alga Plocamium corallorhiza by Michael G. Knott; Henry Mkwananzi; Catherine E. Arendse; Denver T. Hendricks; John J. Bolton; Denzil R. Beukes (1108-1112).
Organic extracts of Plocamium corallorhiza contain three new polyhalogenated monoterpenes, plocoralides A–C (13). Compounds 13 show moderate activity towards esophageal cancer cells.Three new polyhalogenated monoterpenes, plocoralides A–C (13) along with three known compounds (46) have been isolated from the organic extract of the red alga P. corallorhiza. Structures of the new compounds were characterized as 4,8-dibromo-1,1-dichloro-3,7-dimethyl-2E,6E-octadiene (1), 4,6-dibromo-1,1-dichloro-3,7-dimethyl-2E,7-octadiene (2) and 4,8-dibromo-1,1,7-trichloro-3,7-dimethyl-2E,5Z-octadiene (3) on the basis of one- and two-dimensional NMR spectroscopic data and MS analyses. Compounds 26 show moderate cytotoxicity toward esophageal cancer cells.
Keywords: Plocamium corallorhiza; Halogenated monoterpenes; Plocoralides;

Bi-bicyclic and bi-tricyclic compounds from Dendrobium thyrsiflorum by Guang-Nong Zhang; Ling-Yan Zhong; S.W. Annie Bligh; Ying-Li Guo; Chao-Feng Zhang; Mian Zhang; Zheng-Tao Wang; Luo-Shan Xu (1113-1120).
Coumarin–benzofuran, dimeric phenanthrene and phenanthrene–phenanthraquinone derivatives, along with seven known ones, were isolated from Dendrobium thyrsiflorum (Orchidaceae). Four of the compounds showed significant cytotoxic activities against Hela, K-562 and MCF-7 cell lines.One bi-bicyclic and two bi-tricyclic derivatives of coumarin–benzofuran, phenanthrene–phenanthrene and phenanthrene–phenanthraquinone, along with seven known compounds, were isolated from stems of Dendrobium thyrsiflorum Rchb.f. (Orchidaceae). On the basis of chemical, NMR (1H, 13C, HMQC, HMBC and NOESY) and mass spectrometry data, their structures were elucidated as denthyrsin [3-(5′,6′-dimethoxybenzofuran-2′-yl)-6,7-dimethoxy-2H-chromen-2-one; 1], denthyrsinol (4,5′-dimethoxy-[1,1′]biphenanthrenyl-2,5,4′,7′-tetraol; 2), and denthyrsinone (7,4′,7′-trihydroxy-2,2′,8′-trimethoxy-[5,1′]biphenanthrenyl-1,4-dione; 3). Compounds 13 and denthyrsinin (1,5,7-trimethoxyphenanthrene-2,6-diol; 4) showed significant cytotoxic activities against Hela (13.5, 9.3, 9.9 and 2.7 μM, respectively), K-562 (0.45, 1.6, 6.0 and 2.3 μM, respectively) and MCF-7 (18.1, not tested, 3.5 and 4.8 μM, respectively) cell lines.
Keywords: Dendrobium thyrsiflorum; Orchidaceae; Denthyrsin; Denthyrsinol; Denthyrsinone; Cytotoxic activity;

Flavone C-glycosides from flowers of Trollius ledebouri by Jian-Hua Zou; Jun-Shan Yang; Yue-Sheng Dong; Liang Zhou; Geng Lin (1121-1125).
Four flavone C-glycosides, 2″-O-vanilloylvitexin (1), 2″-O-feruloylorientin (2), 2″-O-β-l-galactopyranosylvitexin (3), and 2″-O-β-l-galactopyranosylorientin (4), were isolated from the flowers of Trollius ledebouri, respectively.The ethanol extract of the flowers of Trollius ledebouri yielded four flavone C-glycosides, 2″-O-vanilloylvitexin, 2″-O-feruloylorientin, 2″-O-β-l-galactopyranosylvitexin, and 2″-O-β-l-galactopyranosylorientin, along with known compounds, 6″-O-acetylorientin, 2″-O-(4‴-hydroxybenzoyl)vitexin, vitexin, and orientin. Their structures were elucidated by means of UV, IR, MS and NMR spectroscopic analyses.
Keywords: Trollius ledebouri reichb; Ranunculaceae; Flavone C-glycosides; Acylated flavone C-glycosides;

Isolation and synthesis of a dimeric dihydrochalcone from Agapanthus africanus by Bukirwa I. Kamara; Dale T.L. Manong; Edward V. Brandt (1126-1132).
A new dimeric dihydrochalcone was isolated from the roots of Agapanthus africanus, and synthesized via a pericyclic [π2s  +  π2s] photocyclo-addition of the corresponding chalcone.A new dimeric dihydrochalcone, rel-(1β,2α)-di-(2,4-dihydroxybenzoyl)-rel-(3β,4α)-di-(4-hydroxyphenyl)-cyclobutane, accompanied by its apparent precursor, the known chalcone isoliquiritigenin, have been isolated from the roots of Agapanthus africanus (Liliaceae). The structure is based on spectroscopic methods including extensive NMR analyses, mass spectrometry and circular dichroism. Conclusions regarding the structure and relative configuration are supported by synthesis of the dimeric dihydrochalcone via a pericyclic [π2s  +  π2s] photocyclo-addition of the corresponding chalcone and consideration of the molecular symmetry involved.
Keywords: Agapanthus africanus; Liliaceae; Isoliquiritigenin; Chalcone; Substituted cyclobutane; Dimeric dihydrochalcone; Molecular symmetry; Synthesis;

Acylated anthocyanins from leaves of Oxalis triangularis by Torgils Fossen; Saleh Rayyan; Maya H. Holmberg; Ha˚vard S. Nateland; Øyvind M. Andersen (1133-1140).
Five novel anthocyanins, the 3-(6-(4-malonylrhamnosyl)glucoside)-5-glucoside (2), the 3-(6-rhamnosylglucoside)-5-(6-malonylglucoside) (3), the 3-(6-(4-malonylrhamnosyl)glucoside)-5-(6-malonylglucoside) (4), the 3-(6-(4-malonylrhamnosyl)glucoside) (5) and the 3-(6-(Z)-pcoumaroylglucoside)-5-glucoside (6) of malvidin have been isolated from methanolic extracts of leaves of Oxalis triangularis.The novel anthocyanins, malvidin 3-O-(6-O-(4-O-malonyl-α-rhamnopyranosyl)-β-glucopyranoside)-5-O-β-glucopyranoside (2), malvidin 3-O-(6-O-α-rhamnopyranosyl-β-glucopyranoside)-5-O-(6-O-malonyl-β-glucopyranoside) (3), malvidin 3-O-(6-O-(4-O-malonyl-α-rhamnopyranosyl)-β-glucopyranoside)-5-O-(6-O-malonyl-β-glucopyranoside) (4), malvidin 3-O-(6-O-(4-O-malonyl-α-rhamnopyranosyl)-β-glucopyranoside) (5) and malvidin 3-O-(6-O-(Z)-p-coumaroyl-β-glucopyranoside)-5-O-β-glucopyranoside (6), in addition to the 3-O-(6-O-α-rhamnopyranosyl-β-glucopyranoside)-5-O-β-glucopyranoside (1) and the 3-O-(6-O-(E)-p-coumaroyl-β-glucopyranoside)-5-O-β-glucopyranoside (7) of malvidin have been isolated from purple leaves of Oxalis triangularis A. St.-Hil. In pigments 2, 4 and 5 a malonyl unit is linked to the rhamnose 4-position, which has not been reported previously for any anthocyanin before. The identifications were mainly based on 2D NMR spectroscopy and electrospray MS.
Keywords: Oxalis triangularis; Purple shamrock; Leaves; Colour; Acylated anthocyanins; 4-Malonylated rhamnose; 2D NMR;

Anthraquinones from Hedyotis capitellata by Rohaya Ahmad; Khozirah Shaari; Nordin Hj. Lajis; Ahmad Sazali Hamzah; Nor Hadiani Ismail; Mariko Kitajima (1141-1147).
Four new furanoanthraquinones together with four known anthraquinones and scopoletin were isolated from the stems of Hedyotis capitellata. Lucidin-3-O-β-glucoside was isolated from the roots of the plant.Four new furanoanthraquinones, 2-hydroxymethyl-3,4-[2′-(1-hydroxy-1-methylethyl)-dihydrofurano]-8-hydroxyanthraquinone, 2-hydroxymethyl-3,4-[1′-hydroxy-2′-(1-hydroxy-1-methylethyl)-dihydrofurano]-8-hydroxyanthraquinone, 2-hydroxymethyl-3,4-[2′-1-hydroxy-1-methylethyl)-dihydrofurano]anthraquinone and 2-methyl-3,4-[2′-(1-hydroxy-1-methylethyl)-dihydrofurano] anthraquinone or capitellataquinone A–D and four known anthraquinones, rubiadin, anthragallol 2-methyl ether, alizarin 1-methyl ether and digiferruginol, together with scopoletin were isolated from the stems of Hedyotis capitellata Wall (Rubiaceae). Lucidin-3-O-β-glucoside was isolated from the roots of the plant. Characterization of the new compounds was carried out by extensive NMR studies using FGCOSY, FGHMQC, FGHMBC and DEPT-135 in addition to other spectroscopic methods.
Keywords: Hedyotis capitellata; Rubiaceae; Furanoanthraquinone; Capitellataquinone A, B, C and D;

Xanthones from Garcinia cowa Roxb. latex by W. Mahabusarakam; P. Chairerk; W.C. Taylor (1148-1153).
Five xanthones named cowagarcinone A–E together with six known compounds were isolated from the latex of Garcinia cowa. The crude latex and isolated compounds were investigated for their radical scavenging activities.Five xanthones named cowagarcinone A–E and six previously reported xanthones were isolated from the latex of Garcinia cowa Roxb. Their structures were determined on the basis of spectroscopic analysis. The crude latex and the isolated compounds were investigated for their radical scavenging activities.
Keywords: Garcinia cowa; Guttiferae; Xanthones; Radical scavenging;

Glaucacyclopeptide A from the seeds of Annona glauca by Alassane Wélé; Idrissa Ndoye; Yanjun Zhang; Jean-Paul Brouard; Jean-Louis Pousset; Bernard Bodo (1154-1157).
The structure of glaucacyclopeptide A was determined on the basis of its MS/MS fragmentation, chemical degradation and extensive 2D NMR.The seeds of Annona glauca furnished two cyclopeptides one of which is novel. The structure was elucidated on the basis on mass spectrometry, 2D NMR methods and amino acids analysis.
Keywords: Annona glauca; Annonaceae; Cyclopeptide; Glaucacyclopeptide A;

Indole alkaloids from the leaves of Philippine Alstonia scholaris by Allan Patrick G. Macabeo; Karsten Krohn; Dietmar Gehle; Roger W. Read; Joseph J. Brophy; Geoffrey A. Cordell; Scott G. Franzblau; Alicia M. Aguinaldo (1158-1162).
Manilamine, a seco-uleine alkaloid identified for the first time from the genus Alstonia, and N 4-methyl angustilobine B were isolated from the leaves of the Philippine medicinal plant, Alstonia scholaris.The first seco-uleine alkaloids, manilamine (1) (18-hydroxy-19,20-dehydro-7,21-seco-uleine) and N 4-methyl angustilobine B (2), were isolated from the (pH 5) alkaloid extract of Philippine Alstonia scholaris leaves together with the known indole alkaloids 19,20-(E)-vallesamine (3), angustilobine B N 4-oxide (4), 20(S)-tubotaiwine (5), and 6,7-seco-angustilobine B (6). The structure of the alkaloids was established from MS and NMR experiments.
Keywords: Alstonia scholaris; Apocynaceae; Manilamine; N 4-Methyl angustilobine B; Mass spectrometry; NMR spectroscopy; Monoterpene indole alkaloid biogenesis;

An unusual quinolinone alkaloid from Waltheria douradinha by Solange C.S.M. Hoelzel; Eleno R. Vieira; Sandro R. Giacomelli; Ionara I. Dalcol; Nilo Zanatta; Ademir F. Morel (1163-1167).
The chemical investigation of the methanolic extract of the root bark of Waltheria douradinha (Sterculiaceae) afforded waltherione-A, an unusual quinolinone alkaloid.The chemical investigation of the methanolic extract of the root bark of Waltheria douradinha (Sterculiaceae) afforded an unusual quinolinone alkaloid named waltherione-A (1). Its structure was determined mainly by NMR spectroscopic methods. The antibacterial activity of waltherione-A (1) and the corresponding O-methylated derivative (2) was tested against three Gram-negative and three Gram-positive bacteria, with only (2) having moderate activity.
Keywords: Waltheria douradinha; Sterculiaceae; Quinolinone-alkaloid; Structure determination; Antibacterial activity;

Leishmanicidal cycloartane-type triterpene glycosides from Astragalus oleifolius by Meltem Özipek; Ali A. Dönmez; İhsan Çalış; Reto Brun; Peter Rüedi; Deniz Tasdemir (1168-1173).
Two new cycloartane-type glycosides oleifoliosides A (1) and B (2) were isolated from the lower stem parts of Astragalus oleifolius and evaluated for in vitro trypanocidal, leishmanicidal and antiplasmodial activities as well as their cytotoxic potential on primary mammalian (L6) cells. Their structures were identified as 3-O-[β-xylopyranosyl-(1 → 2)-α-arabinopyranosyl]-6-O-β-xylopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane and 3-O-[β-xylopyranosyl-(1 → 2)-α-arabinopyranosyl]-6-O-β-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, respectively, by means of spectroscopic methods (IR, 1D and 2D NMR, ESI-MS).Two new cycloartane-type glycosides oleifoliosides A (1) and B (2) were isolated from the lower stem parts of Astragalus oleifolius. Their structures were identified as 3-O-[β-xylopyranosyl-(1 → 2)-α-arabinopyranosyl]-6-O–β-xylopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane and 3-O-[β-xylopyranosyl-(1 → 2)-α-arabinopyranosyl]-6-O–β-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, respectively, by means of spectroscopic methods (IR, 1D and 2D NMR, ESI-MS). Three known cycloartane glycosides cyclocanthoside E (3), astragaloside II (4) and astragaloside IV (5) were also isolated and characterized. All five compounds were evaluated for in vitro trypanocidal, leishmanicidal and antiplasmodial activities as well as their cytotoxic potential on primary mammalian (L6) cells. Except for the compound 5, all compounds showed notable growth inhibitory activity against Leishmania donovani with IC50 values ranging from 13.2 to 21.3 μg/ml. Only weak activity against Trypanosoma brucei rhodesiense was observed with the known compounds astragaloside II (4, IC50 66.6 μg/ml) and cyclocanthoside E (3, IC50 85.2 μg/ml), while all compounds were inactive against Trypanosoma cruzi and Plasmodium falciparum. None of the compounds were toxic to mammalian cells (IC50’s > 90 μg/ml). This is the first report of leishmanicidal and trypanocidal activity of cycloartane-type triterpene glycosides.
Keywords: Astragalus oleifolius; Leguminosae; Cycloartane-type glycoside; Oleifoliosides A and B; Trypanosoma; Leishmania; Plasmodium;

Prenylated anthronoid antioxidants from the stem bark of Harungana madagascariensis by Simeon F. Kouam; Bonaventure T. Ngadjui; Karsten Krohn; Pascal Wafo; Asma Ajaz; M. Iqbal Choudhary (1174-1179).
Two new prenylated anthronoids, harunmadagascarins A and B, were isolated from the stem bark of Harungana madagascariensis.Two new prenylated anthronoids, harunmadagascarins A and B, were isolated from the stem bark of Harungana madagascariensis along with six known compounds including two anthronoids: harunganol B and harungin anthrone, one benzophenone: methyl 3-formyl-2,4-dihydroxy-6-methyl benzoate and three pentacyclic triterpenes: friedelin, lupeol and betulinic acid. Harunmadagascarins A and B were characterized as 8,9-dihydroxy-4,4-bis-(3,3-dimethylallyl)-6-methyl-2,3-(2,2-dimethylpyrano)anthrone and 8,9-dihydroxy-4,4,5-tris-(3,3-dimethylallyl)-6-methyl-2,3-(2,2-dimethylpyrano)anthrone, respectively. The structures of these secondary metabolites were determined by spectroscopic means and comparison with the published data. Methyl 3-formyl-2,4-dihydroxy-6-methyl benzoate was isolated for the first time from a plant. Harunmadagascarins A and B, harunganol B and harungin anthrone exhibited significant antioxidant activity.
Keywords: Harungana madagascariensis; Hypericaceae; Prenylated anthronoids; Harunmadagascarins A and B; Antioxidant;

Steryl epoxide, secobutanolide and butanolides from the stem wood of Machilus zuihoensis by Ming-Jen Cheng; Ian-Lih Tsai; Shoiw-Ju Lee; Bolleddula Jayaprakasam; Ih-Sheng Chen (1180-1185).
The dimeric steryl epoxide, machillene (1), the secobutanolide, secomahubanolide (2), and two butanolides, zuihoenalide (3), and 3-(1-methoxyoctadecyl)-5-methylene-5H-furan-2-one (4), together with 12 known compounds, have been isolated from the stem wood of Machilus zuihoensis. Their structures were determined by means of spectroscopic analyses. Machillene (1) showed cytotoxic activity against NUGC-3 and HONE-1 cancer cell lines in vitro.A steryl epoxide, machillene (1), a secobutanolide, secomahubanolide (2), and two butanolides, zuihoenalide (3), and 3-(1-methoxyoctadecyl)-5-methylene-5H-furan-2-one (4), together with 12 known compounds, were isolated from stem wood of Machilus zuihoensis. Their structures were determined by means of spectroscopic analyses. Machillene (1) showed cytotoxic activity against NUGC-3 and HONE-1 cancer cell lines in vitro.
Keywords: Machilus zuihoensis; Lauraceae; Stem wood; Steryl epoxide; Machillene; Secobutanolide; Secomahubanolide; Butanolides; Zuihoenalide; 3-(1-Methoxy-octadecyl)-5-methylene-5H-furan-2-one; Cytotoxicity;

A sugar ester and an iridoid glycoside from Scrophularia ningpoensis by Anh-Tho Nguyen; Jeanine Fontaine; Hugues Malonne; Magda Claeys; Michel Luhmer; Pierre Duez (1186-1191).
A new sugar ester, ningposide D (1) and a new iridoid glycoside, scrophuloside B4 (2) together with six known compounds were isolated from cytotoxic extracts of the roots of Scrophularia ningpoensis. Their structures were established on the basis of spectral evidence. The isolated compounds: oleanonic acid, ursolonic acid, β-sitosterol and scrophuloside B4 (2) inhibit the proliferation of several cancer human cell lines, i.e., MCF7, K562, Bowes, T24S and A549.From cytotoxic extracts of the roots of Scrophularia ningpoensis Hemsl. (Scrophulariaceae) a new sugar ester, ningposide D (3-O-acetyl-2-O-p-methoxycinnamoyl-α(β)-l-rhamnopyranose) (1) and a new iridoid glycoside, scrophuloside B4 (6-O-(2″-O-acetyl-3″-O-cinnamoyl-4″-O-p-methoxycinnamoyl-α-l-rhamnopyranosyl) catalpol) (2) along with known compounds: oleanonic acid (3), ursolonic acid (4), cinnamic acid (5), 3-hydroxy-4-methoxy benzoic acid (6), 5-(hydroxymethyl)-2-furfural (7) and β-sitosterol (8) were isolated. The structures of the new compounds were elucidated by spectral data (1, 2D NMR, EI, HRESI-MS and MS/MS). Oleanonic acid (3) and ursolonic acid (4) were found to be cytotoxic against a series of human cancer cell lines with IC50  = 4.6, 15.5 μM on MCF7; 4.2, 14.5 μM on K562; 14.8, 44.4 μM on Bowes; 24.9, 43.6 μM on T24S; 61.3, 151.5 μM on A549, respectively. β-Sitosterol (8) inhibited Bowes cells growth at IC50  = 36.5 μM. Scrophuloside B4 (2) showed activity on K562 and Bowes cells at IC50  = 44.6, 90.2 μM, respectively.
Keywords: Scrophularia ningpoensis; Sugar ester; Iridoid glycoside; Ningposide D; Scrophuloside B4; Cytotoxicity;

by Wayne W. Carmichael (1192).