Rothmanniamide and other constituents from the leaves of Rothmannia hispida (K.Schum.) fagerl. (Rubiaceae) and their chemophenetic significance

The chemical investigation of the CH₂Cl₂/MeOH (1:1) extract of the leaves of Rothmannia hispida (K. Schum.) Fagerl. (Rubiaceae) led to the isolation of a new ceramide rothmanniamide (1) and a naturally isolated alkyl cinnamate derivative n-heptadecyl-4-hydroxy-trans-cinnamate (2), along with fifteen known compounds including lupeol palmitate (3), lupeol (4), a mixture of uvaol (5) and erythrodiol (6), ursolic acid (7), 30-nor-2α,3β-dihydroxyurs-12-ene (8), hederagenin (9), stigmast-22-en-3-ol (10), a mixture of β-sitosterol (11) and stigmasterol (12), stigmast-4,22-dien-3-ol (13), stigmasterol 3-O-β-D-glucoside (14), triacontan-1-ol (15), kaempferol 3-O-β-D-glucopyranoside (16) and D-mannitol (17). Their structures were elucidated with the help of MS and NMR data. Compounds 8, 10 and 15 were isolated for the first time from the Rubiaceae family. The crude extract and the isolates were assessed in vitro for their antileishmanial activity against Leishmania donovani 1 S (MHOM/SD/62/1 S) promastigotes and cytotoxicity on RAW 264.7 macrophage cells. Compounds 7 and 8 exhibited a highly potent antileishmanial activity with IC₅₀ values of 0.88 and 1.75 μg/mL, respectively, with good selectivity indexes (SI > 57). The chemophenetic significance of these compounds is also discussed.     

Antibacterial and antioxidant activities of compounds isolated from the leaves of Symphonia globulifera (Clusiaceae) and their chemophenetic significance

The phytochemical study was done on the methanol extract from of the leaves of Symphonia globulifera. This plant has been used in traditional medicine to treat of different ailments such as malaria, diseases of the skin, diabetes, cough, intestinal worms, pre-hepatic jaundice and fever. Chromatographic fractionation and purification of this extract led to the isolation and characterization of twelve compounds (1–12) including pristriol (1), robustaflavone (2), polycarpol (3), 7''-O-methylrobustaflavone (4), amentoflavone (5), stigmasterol glucoside (6), epicatechin (7), apigenin (8), luteolin (9), 1,5-dihydroxyxanthone (10), β-sitosterol 3-β-D-glucopyranoside (11) and a mixture of stigmasterol and β-sitosterol (12). The structures of compounds 1–12 were elucidated on the basis of 1D and 2D NMR, mass spectrometric and the spectroscopic data as well as comparison with the literature. All these compounds were isolated for the first time from Symphonia genus. The NMR spectra and structure elucidation of compound 1 were reported for the first in the literature. The antibacterial and antioxidant activities of three of these compounds were evaluated. The chemophenetic significance of these compounds is also discussed.     

Vernoguinamide: A new ceramide and other compounds from the root of Vernonia guineensis Benth. and their chemophenetic significance

The chemical investigation of the roots of Vernonia guineensis Benth. (Asteraceae) resulted in the isolation of a new ceramide, named vernoguinamide (1), together with fifteen known compounds, including three anthraquinones, physion (2), erythroglaucin (3) and emodin (4), three triterpenoids, hop-17(21)-en-3β-yl acetate (5), lupeol (6) and betulinic acid (7), six steroids, vernoguinoside A (8), vernoguinoside (9), β-sitosterol 3-O-β-D-glucoside (10), stigmasterol 3-O-β-D-glucoside (11), stigmasterol (12) and β-sitosterol (13) and three fatty acid derivatives, tetracosanoic acid (14), tricosanic acid (15) and arachidic acid glycerol ester (16). The structure of the new compound as well as those of the known compounds were established by spectrometric analysis including HRESI-MS, 1D and 2D-NMR and by comparison with the previously reported data. Among these compounds, the anthraquinones 2–4 and the triterpene 5 were isolated for the first time from Vernonia genus and compounds 6, 7 and 14–16 were extracted for the first time from the species. The isolated compounds were tested for their antibacterial activity and 3, 8 and 9 were the most active compounds against the tested bacteria. Furthermore, the chemophenetic relationships of the isolated compounds and their significance were also discussed.     

Triterpenoids from the seedpods of Holarrhena curtisii King and Gamble

Two new hydroperoxy pentacyclic triterpenoids, 3β-hydroxy-11α-hydroperoxyolean-12-en-28-oic acid (1) and 3β-hydroxy-11α-hydroperoxyursan-12-en-28-oic acid (2), together with nine known triterpenoids, squalene (3), β-amyrin acetate (4), α-amyrin acetate (5), lupeol acetate (6), lupeol (7), lanosta-7,24-dien-3β-ol (8), cycloeucalenol (9), oleanolic acid (11) and ursolic acid (12), a known phytosterol, 24-methylenepollinastanol (10), and two known flavanols, (–)-catechin (13) and (–)-gallocatechin (14), were isolated from the methanolic extract of the fresh seedpods of Holarrhena curtisii. Their structures were determined by spectroscopic analysis (one and two dimensional nuclear magnetic resonance, high resolution electrospray ionization mass spectrometry and attenuated total reflectance-Fourier transform infrared spectroscopy). All compounds (except squalene) were evaluated for their in vitro α-glucosidase inhibitory activity. Compounds 1, 2, 11 and 12, which had a pentacyclic triterpenoid acid skeleton, showed a strong in vitro α-glucosidase inhibitory activity compared to that of the standard control, acarbose.     

Phytochemical and chemotaxonomic study on Berchemiella wilsonii (Schneid.) Nakai

Phytochemical investigation of the aerial parts of Berchemiella wilsonii (Schneid.) Nakai (Rhamnaceae) led to the isolation of four flavonoids (1–4), three phenolic acids (5–7), two megastigmane derivatives (8–9) and one triterpene (10). The structures of these compounds were elucidated as taxifolin (1), (−)-epicatechin (2), quercetin 3-O-a-l-arabinopyranoside (3), vitexin (4), methyl p-hydroxycinnamat (5), 3,4-dihydroxybenzoic acid (6), 2-hydroxy-4-methoxy-3,6-dimethyl benzoic acid (7), (3S,5R,6R,7E,9S)-3,5,6,9-tetrahydroxy-7-en-megastigmane (8), (6S,9R)-roseoside (9) and lupeol (10) on the basis of NMR spectral data and comparison with literature values. These results are the first chemical constituent data of the genus Berchemiella, and the chemotaxonomic significance of these compounds is discussed.     

Constituents of Desmodium salicifolium (Poir.) DC (Fabaceae) with antifungal activity

Phytochemical investigation of the roots of Desmodium salicifolium led to the isolation of two new compounds (Desmoflavanone A: 5,2',4'-trihydroxy-4'',4''-dimethyl-2H-dihydropyranoisoflavanone (1) and desmodioside A: (22R)-3β,22,23-trihydroxyolean-12-en-3-O-α- _L-rhamnopyranosyl-(1→2)-β-_D-glucopyranosyl-(1→2)-β-_D-glucuronopyranoside (2)) together with nine known secondary metabolites including kaikasaponin III (3), spinosin (4), isovitexin (5), β-sitosterol 3-O-β-_D-glucopyranoside (6), neorautenol (7), kaempferol (8), oleanolic acid (9), betulinic acid (10), and lupeol (11). The structures of these compounds were elucidated mainly by extensive spectroscopic analysis, particularly 1D and 2D NMR spectroscopy, electrospray ionization-mass spectrometry and by comparison of their spectroscopic data with those of related compounds reported in the literature. The methanolic extract, EtOAc and n-BuOH fractions as well as some isolated compounds were assessed for their antifungal activities against two fungi using microdilution method. The methanolic extract displayed weak activity against Candida albicans (MIC = 512 µg/mL). The EtOAc fraction also exhibited weak inhibitory effect with MIC of 256 µg/mL against Candida albicans and Candida glabrata. Compound 3 showed moderate effect against Candida glabrata with MIC value of 16 µg/mL while 1 was inactive against both fungi.     

Isolation of hopane triterpenes and other constituents from Machaerium brasiliense vogel (Fabaceae)

Phytochemical study of Machaerium brasiliense leaves extract afforded three hopane triterpenes 3,4-seco-21β-H-hop-22 (29)-en-3-oic acid (1), hopenone B (2), hopene B (3). In addition, lupeol (4), stigmasterol (5), β-sitosterol (6), daucosterol (7), uracil (8), allantoin (9) and trans-4-hydroxy-N-methylproline (10) were isolated. The structures of these compounds were established based on spectroscopic data in comparison to those described in literature. Considering the chemotaxonomic relevance of the isolated compounds, this is the first report of triterpenes 1, 2 and 3 in Fabaceae family and compounds 7, 8 and 9 in the genus Machaerium. Besides, preliminary screening on antiproliferative and antioxidant activities was performed for MBEB and its fractions.     

Alkenylresorcinols and cytotoxic activity of the constituents isolated from Labisia pumila

Phytochemical investigation on the leaves of Labisia pumila (Myrsinaceae), an important medicinal herb in Malaysia, has led to the isolation of 1-O-methyl-6-acetoxy-5-(pentadec-10Z-enyl)resorcinol (1), labisiaquinone A (2) and labisiaquinone B (3). Along with these, 16 known compounds including 1-O-methyl-6-acetoxy-5-pentadecylresorcinol (4), 5-(pentadec-10Z-enyl)resorcinol (5), 5-(pentadecyl)resorcinol (6), (−)-loliolide (7), stigmasterol (8), 4-hydroxyphenylethylamine (9), 3,4,5-trihydroxybenzoic acid (10), 3,4-dihydroxybenzoic acid (11), (+)-catechin (12), (−)-epicatechin (13), kaempferol-3-O-α-rhamnopyranosyl-7-O-β-glycopyranoside (14), kaempferol-4′-O-β-glycopyranoside (15), quercetin-3-O-α-rhamnopyranoside (16), kaempferol-3-O-α-rhamnopyranoside (17), (9Z,12Z)-octadeca-9,12-dienoic acid (18) and stigmasterol-3-O-β-glycopyranoside (19) were also isolated. The structures of these compounds were established on the basis of 1D and 2D NMR spectroscopy techniques (¹H, ¹³C, COSY, HSQC, NOESY and HMBC experiments), mass spectrometry and chemical derivatization. Among the constituents tested 1 and 4 exhibited strongest cytotoxic activity against the PC3, HCT116 and MCF-7 cell lines (IC₅₀ values ⩽10 μM), and they showed selectivity towards the first two-cell lines relative to the last one.     

New flavonoids from the fruits of Cornus mas,Cornaceae

One new β-hydroxychalcone, 4-acetoxy-5,2′,4′,6′,β-pentahydroxy-3-methoxychalcone (1), one new flavanone, 7,3′-dihydroxy-5,4′-dimethoxyflavanone (2) and seven known compounds, 2R, 3R-trans-aromadendrin (3), naringenin-7-O-methylether (4), myricetin (5), quercetin-3-O-rutinoside (6), ursolic acid (7), gallic acid (8) and d-glucose (9) were isolated from the methanolic fruit extract of Cornus mas L. (=Cornus mascula L.), Cornaceae. The structures of the new compounds were elucidated on the basis of extensive spectroscopic methods, including 2D NMR experiments and of known compounds by comparison of physical and spectral data with literature.     

Chemical constituents from Psychotria arborea Hiern (Rubiaceae)

The chemical study of the stems extract of Psychotria arborea Hiern led to the isolation of thirteen compounds, including four anthraquinones: 2-methylanthracene-9,10-dione (1), 2-methoxyanthracene-9,10-dione (2), 2-hydroxy-3-methylanthracene-9,10-dione (3) and 3-hydroxy-1-methoxy-2-methylanthracene-9,10-dione (4); two diterpenes: ent-kaur-16-en-19-oic acid (5) and 15-acetoxy-ent-kaur-16-en-19-oic acid (6); two triterpenes, β-amyrin (8) and oleanolic acid (9), one flavonoid: Quercetin (7), three sterols: A mixture of stigmasterol (10) and β-sitosterol (11) and β-sitosterol-3-O-β-D-glucopyranoside (12) and one fatty acid (13). The structures of these compounds were elucidated based on NMR and HR-ESIMS analysis, further supported by comparison with previously reported spectral data. Compounds 1–4 and compounds 10–12 were tested for their antibacterial activity against three bacteria strains Escherichia coli, Staphylococcus aureus and Salmonella enterica. All these tested compounds were found to be inactive. Furthermore, the chemotaxonomic significance of the obtained compounds was discussed in detail.     

Triterpenoids from Mallotus repandus: Three new δ-lactones

The leaves of Mallotus repandus contain friedelin, 3β-hydroxy-13α-ursan-28,12β-olide (1), its benzoate (2) and ursolic acid. The stems contain friedelin, lupeol, α-amyrin, 2 and 3α-hydroxy-13α-ursan-28, 12β-olide (3), 21α-hop-22(29)-ene-3β,30-diol and ursolic acid. 1–3 are new compounds.     

Furanocoumarins from the twigs of Ficus chlamydocarpa (Moraceae)

Two furanocoumarin derivatives, 3-methoxypsoralen (1) and 3,5-dimethoxypsoralen (2), along with nine known compounds, friedelinol (3), 3-oxo-11β-hydroxyoleanan-12-ene (4), lupeol (5), taraxer-3-one (6), a mixture of β-sitosterone (7a) and stigmast-4,22-dien-3-one (7b), ergosterol (8), 9,19-cyclolanost-3-one-24,25-diol (9), oleanan-12-ene-3,11-dione (10), and β-sitosterol 3-O-β-D-glucopyranoside (11) were isolated from the twigs of Ficus chlamydocarpa. Their structures were established by NMR spectroscopic analyses and HRESIMS. The structure of 1 was further confirmed from its single crystal X-ray diffraction. The crude extract, fractions and some isolated compounds were assessed for their preliminary antibacterial activity and cytotoxicity. One of the fractions (FB-B3) exhibited inhibition against the bacterial strain Pseudomonas agarici and induced a remarkable cytotoxic activity toward the human cervix carcinoma cell line KB-3-1 (IC₅₀ 0.166 mg/mL), and compounds 1, 6, and 7 showed moderate antibacterial activity against Bacillus subtilis and Micrococcus luteus.     

Antiplasmodial anthraquinones and hemisynthetic derivatives from the leaves of Tectona grandis (Verbenaceae)

Chemical investigation of the methanol extract of the leaves of Tectona grandis led to the isolation of one new anthraquinone derivative, grandiquinone A (3-acetoxy-8-hydroxy-2-methylanthraquinone) (1), along with nine known compounds: 5,8-dihydroxy-2-methylanthraquinone (2), hydroxysesamone (3), 3-hydroxy-2-methylanthraquinone (4), quinizarine (5), betulinic acid (6), ursolic acid (7), tectograndone (8), corosolic acid (9) and sitosterol 3-O-β-d-glucopyranoside (10). Compounds 2 and 3 were isolated for the first time from the leaves of this plant, while 5 has never been reported from the genus Tectona. Hydroxysesamone (3) and tectograndone (8) were subjected to cyclisation and acetylation reactions to afford two hemisynthetic derivatives, 6,9-dihydroxy-2,2-(dimethyldihydropyrano)-3,4-dihydro-2H-benzo[g]chromene-5,10-dione (11) and acetyltectograndone (12) respectively, which are reported here for the first time. The ethyl acetate-soluble portion, some of the isolated compounds and hemisynthetic derivatives were evaluated for their antiplasmodial activity against the multidrug-resistant Dd2 strain of Plasmodium falciparum. Compound 3 showed a prominent activity, while 2, 8, 9, 11 and 12 showed significant in vitro anti-malarial activity. Compound 1 was weakly active in this test. The structures of the compounds were elucidated by spectroscopic methods and comparison of the data with the literature.     

New derivatives from the aerial parts of Boerhaavia diffusa L. (Nyctaginaceae)

Boerhaavia diffusa L. is used in the traditional medicine of several Asian countries. The isolation and identification of five new compounds, together with 11 known compounds, from the ethyl acetate extract of the aerial part of B. diffusa grown Vietnam is reported. The structure of the new compounds was established by 1D and 2D NMR spectroscopy, and high resolution ESI-MS analysis. New compounds are two rotenoids: 9,11-dihydroxy-6,10-dimethoxy[1]benzopyrano[3,4-b][1]benzopyran-12(6H)-one (boeravinone P, 3) and 3-[2-(β-d-glucopyranosyloxy)-3-hydroxyphenyl]-5-hydroxy-2-hydroxymethyl-7-methoxy-6-methyl-4H-1-benzopyran-4-one (boeravinone Q, 9), an atropisomeric mixture of two rotenoid glycosides (3′,5-dihydroxy-2-hydroxymethyl-7-methoxy-6-methylisoflavone 2′-O-β-d-glucopyranoside, 11), a sesquiterpene lactone (4,10-dihydroxy-8-methoxyguai-7(11)-en-8,12-olide, 5) and a new phenylpropanoid glycoside (boerhaavic acid, 15).     

Glutathione S-transferase inhibitory,free radical scavenging,and anti-leishmanial activities of chemical constituents of Artocarpus nobilis and Matricaria chamomilla

Glutathione S-transferase (GST) inhibition-directed fractionations on the ethanolic extract of Artocarpus nobilis of Sri Lankan origin yielded four known triterpenoids, cyclolaudenyl acetate (1), lupeol acetate (2), β-amyrine acetate (3), and zizphursolic acid (4), along with five known flavonoids, artonins E (5), artobiloxanthone (6) artoindonesianin U (7), cyclocommunol (8) and multiflorins A (9). Our recent chemical studies on the methanolic extract of Matricaria chamomilla, collected from Manitoba, afforded one new compound, matriisobenzofuran (10), and six known natural products, fraxidin (11), scopoletin (12), apigenin (13), apigenin 7-O-β-glucopyranoside (14), palmatoside A (15) and p-hydroxyacetophenone (16). Compounds 1–16 were identified with the aid of extensive NMR and MS spectral data. Compounds 1–16 exhibited a wide range of GST inhibition activity. Compounds 5–9 exhibited significant anti-oxidant activity in DPPH free radical scavenging assay. Compounds 10 and 11 were also moderately active in anti-leishmanial assay.     

Phytochemical and chemotaxonomic study of Pulsatilla cernua (Thunb.) Bercht. ex J. Presl

Twenty-two compounds were isolated from the 70% EtOH–H₂O extract of Pulsatilla cernua (Thunb.) Bercht. ex J. Presl roots, and their structures were determined based on ¹H NMR, ¹³C NMR and MS spectroscopic data, including (+)-pinoresinol (1), matairesinol (2), 4-ethoxycinnamic acid (3), p-hydroxy ethyl cinnamate (4), 3-(4′-methoxyphenyl)-2(E)-propenoic acid (5), methyl 4-hydroxycinnamate (6), radicol (7), cryptomeridiol (8), fraxinellone (9), diolmycin B2 (10), hederagonic acid (11), hederagenin (12), oleanolic acid (13), 3-O-α-L-arabinopyranosyl-oleanolic acid (14), hederagenin 3-O-α-L-arabinopyranoside (15), 3-O-[α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] oleanolic acid (16), hederasaponin B (17), kizutasaponin K₁₂ (18), patrinia saponin H3 (19), hederacholichiside F (20), cernuoside A (21) and cernuoside B (22). Eight compounds (3–10) were isolated and identified from the genus Pulsatilla for the first time.     

Seven new triterpenoids from the aerial parts of Ilex cornuta and protective effects against H2O2-induced myocardial cell injury

Seven new triterpenoids (1–7), together with two known ones (8–9), were isolated from the aerial parts ofIlex cornuta. The leaves of I. cornuta are the major source of “Kudingcha”, a popular herbal tea consumed in China and other countries. The structures of compounds 1–7 were determined as 20-epi-urs-12,18-dien-28-oic acid 3β-O-α-l-arabinopyranoside (1), 20-epi-urs-12,18-dien-28-oic acid 2′-O-acetyl-3β-O-α-l-arabinopyranoside (2), 20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (3), 3β,23-dihydroxy-20-epi-urs-12,18-dien-28-oic acid (4), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-α-l-arabinopyranoside (5), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronic acid (6), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (7), on the basis of spectroscopic analyses (IR, ESI–MS, HR-ESI–MS, 1D and 2D NMR) and chemical reactions. Protective effects against H₂O₂-induced H9c2 cardiomyocyte injury were tested in vitro for compounds 1–9, and the data showed that compound 4 had significant cell-protective effect. Compounds 1-9 did not show significant DPPH radical scavenging activity.     

Phenolic compounds from the leaves and stem bark of Pseudospondias microcarpa (A. Rich.) Engl. (Anacardiaceae)

Phytochemical study of the leaves and the stem bark of Pseudospondias microcarpa (A. Rich.) Engl. afforded eight phenolic compounds: scopoletin (1), ferulic acid (2), isovitexin (3), rhoifolin (4), quercetin 3-O-α-L-rhamnopyranoside (5), justicialoside A (6), granduloside A (7) and pithecellobiumol B (8). The structures of the isolated compounds were elucidated by spectroscopic means including 1D and 2D NMR and MS, and by comparison with previously reported data. This is the first report on the isolation of these compounds from the genus Pseudospondias. The chemotaxonomic significance of the isolated compounds within the family Anacardiaceae is discussed.     

Chemical constituents from Gentianella turkestanorum (Gentianaceae)

Phytochemical investigation of Gentianella turkestanorum (Gentianaceae) afforded nineteen compounds, including six xanthones (1–6), two triterpenoids (7–8), eight flavones (9–16) and three iridoids (17–19). Here, we firstly reported that 1-hydroxy-3,5-dimethoxyxanthone (4), 1, 8-dihydroxy-3-methoxyxanthone (5), apigenin (9), quercetin (10), luteolin-7-O-glucoside (12) and three other compounds (1, 8-dihydroxy-3-methoxyxanthone (5), apigenin-7-O-gluco (1″ → 3‴) glucoside (15) and luteolin-7-O-gluco (1″ → 3‴) glucoside (16)) could be isolated from G. turkestanorum. The occurrence of chemical data and the sequence data might be employed as common constituents of the genera Gentianella, Lomatogonium and Swertia.     

Fatty acid derivatives and dammarane triterpenes from the glandular trichome exudates of Ibicella lutea and Proboscidea louisiana

Ibicella lutea and Proboscidea louisiana, both of the Martyniaceae family, are known for rich glandular trichomes on their leaves and stems. Chemical investigations of the glandular trichome exudates on leaves of the two plants furnished three types of secondary metabolites, glycosylated fatty acids, glycerides (2-O-(3,6-diacetyloxyfattyacyl)glycerols and 2-O-(3-acetyloxyfattyacyl)glycerols) and dammarane triterpenes. The glycosylated fatty acids from I. lutea were determined to be 6(S)-(6-O-acetyl-β-d-glucopyranosyloxy)-octadecanoic acid (1A), -eicosanoic acid (1B) and -docosanoic acid (1C), as well as their respective deacetyl congeners (2A, 2B and 2C), whereas P. louisiana furnished 8(S)-(6-O-acetyl-β-d-glucopyranosyloxy)-eicosanoic acid (3A) and -docosanoic acid (3B) and their respective deacetyl congeners (4A and 4B), together with 2B. Both plants contained 12 identical 2-O-[(3R,6S)-3,6-diacetyloxyfattyacyl]glycerols (5A-L), in which the fatty acyl moieties contained between 17 and 21 carbon atoms. The corresponding mono-acetyloxy compounds, 2-O-[(3R)-3-acetyloxyfattyacyl]glycerols (6A–L) were detected in both plants. Among these glycerides, ten compounds (5A, 5C, 5F, 5H, 5K, 6A, 6C, 6F, 6H and 6K) had iso-fattyacyl structures and four (5E, 5J, 6E and 6J) had anteiso-fattyacyl structures. A previously unknown dammarane triterpene, betulatriterpene C 3-acetate (7), was isolated together with three known dammarane triterpenes, 24-epi-polacandrin 1,3-diacetate (8), betulatriterpene C (9) and 24-epi-polacandrin 3-acetate (10) from I. lutea, whereas 12 dammarane triterpenes, named probosciderols A–L (12–23), and the known compound betulafolienetriol (11) were isolated from P. louisiana. The structures of these compounds were elucidated by spectroscopic analysis including 2D-NMR techniques and chemical transformations. The 6-O-acetylglucosyloxy-fatty acids 1A–C (42%) and the dammarane triterpenes 7–10 (31%) were the two most abundant constituents in the glandular trichome exudate of I. lutea, whereas the dammarane triterpenes 11–23 (47%) and the glucosyloxy-fatty acids (4A, 4B and 2B) (38%) were the most abundant constituents in the glandular trichome exudate of P. louisiana.