New cyclopropyl-triterpenoids from the aerial roots of Ficus microcarpa

Triterpenes from antler-shaped fruiting body of Ganoderma lucidum and their hepatoprotective activities

Seven previously undescribed triterpenes (1-7), as well as one triterpene (8) previously described as a synthetic product, were isolated from the antler-shaped fruiting body of Ganoderma lucidum. Their structures were established based on comprehensive spectroscopy analysis. At a concentration of 10 μM, (24E)-3-oxo-15α-acetoxy-lanosta-7,9(11),24-trien-26-al (3) and (24R,25S)-3-oxo-lanosta-7,9(11)-dien-25-ethoxyl-24,26-diol (5) provided significant protection against acetaminophen-induced necrosis in human HepG2 liver cancer cells, and the cell survival rates were 69.7 and 76.1% respectively, similar to that of the positive control (glutathione, 72.1%). Based on the present results, these compounds could be potential hepatoprotective agents.

Design, modification of phyllanthone derivatives as anti-diabetic and cytotoxic agents

Twelve benzylidene derivatives, one Baeyer-Villiger oxidative, six imine derivatives were successfully designed and synthesised from phyllanthone. In the search for potential new anti-diabetic agents, phyllanthone along with its benzylidene and oxidation analogues were evaluated for enzyme inhibition against α-glucosidase. In the benzylidene series, most analogues displayed stronger activity than the mother compound. Compound 1c revealed the strongest activity, outperforming the acarbose positive control with an IC₅₀ value of 19.59 µM. Phyllanthone and its derivatives were then tested for cytotoxic activity against the K562 cell line. The imine analogues displayed the most powerful cytotoxic activity with 3cand 3d having IC₅₀ values of 57.55 and 68.02 µM, respectively.

13,27-Cycloursane, ursane and oleanane triterpenoids from the leaves of Lucuma nervosa

One hitherto unknown 24-nor-13,27-cycloursane-type triterpenoid, lucumic acid A (1), one new 24-nor-ursane triterpenoid, lucumic acid B (2), along with six known triterpenoids were isolated from the ethanol extract of the leaves of Lucuma nervosa. Their structures were established on the basis of spectroscopic data interpretation. Lucumic acid A (1) is the first example of a 24-nor-triterpenoid with a 13,27-cyclopropane ring.

Propellanes-From a Chemical Curiosity to "Explosive" Materials and Natural Products

Propellanes are a unique class of compounds currently consisting of well over 10 000 representatives, all featuring two more or less inverted tetrahedral carbon atoms that are common to three bridging rings. The central single bond between the two bridgeheads is significantly weakened in the smaller entities, which leads to unusual reactivities of these structurally interesting propeller-like molecules. This Review highlights the synthesis of such propellanes and their occurrence in material sciences, natural products, and medicinal chemistry. The conversion of [1.1.1]propellane into bridgehead derivatives of bicyclo[1.1.1]pentane, including oligomers and polymers with bicyclo[1.1.1]penta-1,3-diyl repeat units, is also featured. A selection of natural products with larger propellane subunits are discussed in detail. Heteropropellanes and inorganic propellanes are also addressed. The historical background is touched in brief to show the pioneering work of David Ginsburg, Günther Snatzke, Kenneth B. Wiberg, Günter Szeimies, and others.

Polyoxygenated ursane and oleanane triterpenes from Siphonodon celastrineus

Twenty polyoxygenated triterpenes, including nineteen ursanes and one oleanane, were characterized from the stem material of Siphonodon celastrineus (Celastraceae) through the application of spectroscopic techniques and chemical transformation. Three of the ursane-type triterpenoids possessed the rare 13,27-cyclopropane ring skeleton.

New ursane triterpenoids from Ficus pandurata and their binding affinity for human cannabinoid and opioid receptors

Phytochemical investigation of Ficus pandurata Hance (Moraceae) fruits has led to the isolation of two new triterpenoids, ficupanduratin A [1β-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (11) and ficupanduratin B [21α-hydroxy-3β-acetoxy-11α-methoxy-urs-12-ene] (17), along with 20 known compounds: α-amyrin acetate (1), α-amyrin (2), 3β-acetoxy-20-taraxasten-22-one (3), 3β-acetoxy-11α-methoxy-olean-12-ene (4), 3β-acetoxy-11α-methoxy-12-ursene (5), 11-oxo-α-amyrin acetate (6), 11-oxo-β-amyrin acetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione (9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), β-sitosterol (13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3β,21β-dihydroxy-11α-methoxy-olean-12-ene (16), 3β-hydroxy-11α-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11α,21α-dihydroxy-3β-acetoxy-urs-12-ene (21), and β-sitosterol-3-O-β-D-glucopyranoside (22). Compound 21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on the basis of IR, 1D ((1)H and (13)C), 2D ((1)H-(1)H COSY, HSQC, HMBC and NOESY) NMR and MS spectroscopic data, in addition to comparison with literature data. The isolated compounds were evaluated for their anti-microbial, anti-malarial, anti-leishmanial, and cytotoxic activities. In addition, their radioligand displacement affinity on opioid and cannabinoid receptors was assessed. Compounds 4, 11, and 15 exhibited good affinity towards the CB2 receptor, with displacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds in the active site of the CB2 cannabinoid receptors was investigated through molecular modelling.

The chemistry and bioactivity of Southern African flora I: a bioactivity versus ethnobotanical survey of alkaloid and terpenoid classes

As a whole, the African continent is highly endowed with a huge floral biodiversity.

Ficuschlorins A - D, lactone Chlorins from the leaves of ficus microcarpa

Four new lactone chlorins, ficuschlorins A - D (1-4, resp.), and six known pheophytins were isolated from the leaves of Ficus microcarpa. The structures of these compounds were determined by 1D- and 2D-NMR spectroscopy, and other techniques. New natural pheophytins were rarely obtained. In the past ten years, only three new pheophytins were isolated from natural sources.

Cytotoxic Hexacyclic Triterpene Acids from Euscaphis japonica

Six hexacyclic triterpene acids (1-6), named euscaphic acids A-F, and eight known triterpene acid compounds (7-14) were isolated from an ethanolic extract of twigs of Euscaphis japonica. Compounds 8 and 10 were isolated for the first time from a natural source. Triterpenes 1-6 possess hexacyclic skeletons with a 13α,27-cyclopropane ring. Structural elucidation of compounds 1-6 was established by spectroscopic methods, especially 2D NMR techniques ((1)H-(1)H COSY, HMQC, HMBC, and NOESY). Compounds 3, 4, and 14 showed significant cytotoxicity against different cancer cell lines [IC50 = 2.54 (NCI-H460), 3.61 (MCF-7), and 3.27 μM (CEM) for 3, 4, and 14, respectively].

Preparative Isolation and Purification of Flavone C-Glycosides from the Leaves of Ficus microcarpa L. f by Medium-Pressure Liquid Chromatography, High-Speed Countercurrent Chromatography, and Preparative Liquid Chromatography

Combined with medium-pressure liquid chromatography (MPLC) and preparative high-performance liquid chromatography (perp-HPLC), high-speed countercurrent chromatography (HSCCC) was applied for separation and purification of flavone C-glycosides from the crude extract of leaves of Ficus microcarpae L. f. HSCCC separation was performed on a two-phase solvent system composed of methyl tert- butyl ether - ethyl acetate - 1-butanol - acetonitrile - 0.1% aqueous trifluoroacetic acid at a volume ratio of 1:3:1:1:5. Partially resolved peak fractions from HSCCC separation were further purified by preparative HPLC. Four well-separated compounds were obtained and their purities were determined by HPLC. The purities of these peaks were 97.28%, 97.20%, 92.23%, and 98.40%.. These peaks were characterized by ESI-MS(n). According to the reference, they were identified as orientin (peak I), isovitexin-3″-O-glucopyranoside (peak II), isovitexin (peak III), and vitexin (peak IV), yielded 1.2 mg, 4.5 mg, 3.3 mg, and 1.8 mg, respectively.

Triterpenoids and aromatics from Derris laxiflora

Seven new compounds, O-trans-cinnamoylglutinol (1), 22β-hydroxy-12-oleanen-3-one (2), 15α,16α-epoxy-12-oleanen-3-one (3), 29-hydroxy-12-oleanene-3,22-dione (4), 22β,29-dihyroxy-12-oleanen-3-one (5), 2,3-(methylenedioxy)-4-methoxy-5-methylphenol (8), and 2,3,6-trimethoxy-5-methylphenol (9), as well as two first isolated from natural sources, 25-cycloartene-3,24-dione (6) and 24ξ-hydroxy-25-cycloarten-3-one (7), were characterized from Derris laxiflora. The structures of these compounds were determined by analysis of their spectroscopic data.

Water-soluble constituents from aerial roots of Ficus microcarpa

Three new water-soluble constituents [ficuscarpanoside B (1), (7E,9Z)-dihydrophaseic acid 3-O-beta-D-glucopyranoside (4) and ficuscarpanic acid (6)] and the natural product 2,2'-dihydroxyl ether (7) have been isolated, together with three known compounds [(7S,8R)-syringoylglycerol (2), (7S,8R)-syringoylglycerol-7-O-beta-D-glucopyranoside (3) and icariside D2 (5)] from the aerial roots of Ficus microcarpa. Identification of their structures was achieved by 1D and 2D NMR experiments, including 1H-1H COSY, NOESY, HMQC and HMBC methods and FAB mass spectral data.

Euphoportlandols A and B, tetracylic diterpene polyesters from Euphorbia portlandica and their anti-MDR effects in cancer cells

Two new tetracyclic diterpene polyesters, euphoportlandols A (1) and B (2), have been isolated along with 12 known tetracyclic triterpenes from an acetone extract of Euphorbia portlandica. Their structures were established as 5alpha,11alpha,14alpha,17-tetraacetoxy-3beta-benzoyloxy-6beta,15beta-dihydroxy-9-oxoseget-8(12)-ene (1) and 5alpha,11alpha,14alpha,17-tetraacetoxy-3beta-benzoyloxy-6beta,15beta-dihydroxy-9-oxosegetane (2), respectively, by spectroscopic data interpretation. Compounds 1 and 2 were evaluated for their ability to inhibit multidrug resistance in cancer cells. Both compounds were found to be inhibitors of P-glycoprotein activity.

Novel triterpenoids from the aerial roots of Ficus microcarpa

Three novel triterpenoids, 3beta-acetoxy-11alpha-hydroxy-11(12-->13)abeooleanan-12-al (1), 3beta-hydroxy-20-oxo-29(20-->19)abeolupane (2), and 29,30-dinor-3beta-acetoxy-18,19-dioxo-18,19-secolupane (3), and the known 4, 5a, and 5b were isolated from the aerial roots of Ficus microcarpa. Their structures were elucidated on the basis of 2D NMR and X-ray diffraction experiments. Compound 1, derived from the oleanane skeleton, has an unusual five-membered C ring. Compounds 2 and 3, derived from the lupane skeleton, have unique skeletons that may arise from the same biogenetic pathway.