A new eudesmane derivative and a new fatty acid ester from Sambucus williamsii

1,4,13-Trihydroxy-eudesm-11(12)-ene, a new eudesmane derivative (3), (9E)-8,11,12-trihydroxyoctadecenoic acid methyl ester, a new fatty acid ester (2) and tianshic acid (1) were obtained from the stems of Sambucus williamsii. Their structures were elucidated by physiochemical properties and spectroscopic analysis. Both compounds 1 and 2 showed stimulating effects on alkaline phosphatase activity of the osteoblastic UMR106 cell about 1.5 fold at 30 mumol/l while they had no effects on cell proliferation.     

Agropine,a new amino acid derivative from crown gall tumours

Agropine, an unusual compound produced in plant tumours was shown by mass spectrometry and proton and carbon-13 nmr spectroscopy to be a bicyclic derivative of glutamic acid and a hexitol sugar.     

A new ellagic acid derivative from Polygonum runcinatum

A new ellagic acid derivative, 3,3′-dimethylellagic acid-4′-O-(6″-galloyl)-β-d-glucoside, named runcinatside (5), together with four known compounds 3,3′-dimethylellagic acid (1), 3,3′,4′-trimethylellagic acid (2), 3,3′-dimethylellagic acid-4′-O-β-d-glucoside (3) and 3-methylellagic acid-4′-O-α-l-rhamno-pyranoside (4), was isolated from the roots of Polygonum runcinatum Buch.-Ham. ex D.Don Var. sinense Hemsl and the structures of these compounds were established by spectroscopic methods and comparison with previously reported data. All compounds showed antioxidant activities in vitro and compound 5 possessed the highest activity.     

(+)-Kunstlerone, a new antioxidant neolignan from the Leaves of Beilschmiedia kunstleri gamble

A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 μg/mL.     

Eucleanal: a new napthalene derivative from Euclea divinorum

A new naphthalene derivative, named eucleanal (1), was isolated from Euclea divinorum Hiern., and its structure elucidated by detailed spectroscopic (1H, 13C NMR, COSY, HMQC, HMBC) and HREIMS analysis.     

A new flavellagic acid derivative and phloroglucinol from Rhodomyrtus tomentosa

A new flavellagic acid derivative, 3,3',4,4'-tetra-O-methylflavellagic acid and six known compounds were isolated from the stems of Rhodomyrtus tomentosa while a new phloroglucinol, named rhodomyrtosone I, and six known compounds were isolated from the fruit. Their structures were elucidated by spectroscopic analyses as well as by comparisons with related compounds.     

A new coruleoellagic acid derivative from stems of Rhodamnia dumetorum

A new coruleoellagic acid derivative, 3,3′,4,4′,5′-pentamethylcoruleoellagic acid (1) together with nine known compounds, hexamethylcoruleoellagic acid (2), 3,4,3′-tri-O-methylellagic acid (3), heptaphylline (4), 7-methoxymukonal (5), dentatin (6), sinapaldehyde (7), gallic acid (8), 2,6-dimethoxy-4H-pyran-4-one (9) and β-sitosterol (10) were isolated from the stems of Rhodamnia dumetorum. Their structures were identified by physical and spectroscopic data (IR, 1D and 2D NMR, and MS). Compounds 1, 2 and 7-10 were tested for antibacterial activity against six pathogenic bacterial strains (Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Methicillin resistant S. aureus (MRSA)).     

Psychotripine: a new trimeric pyrroloindoline derivative from Psychotria pilifera

Psychotripine, a trimeric pyrroloindoline derivative with an unprecedented hendecacyclic system bearing a hexahydro-1,3,5-triazine unit, was isolated from the leaves of Psychotria pilifera. The structure was elucidated on the basis of spectroscopic and quantum theory. A possible biogenesis was also postulated.     

Synthesis of a cisplatin derivative from lithocholic acid

A new steroidal-platinum(II) hybrid compound was synthesized using a simple and efficient methodology. The synthesis was performed by a convergent approach with cross metathesis (CM) as a key step. An olefin derived from lithocholic acid and a vinyl substituted ethylenediamine derived from l-serine were used as chiral building blocks, which were combined in the CM step. The most important advantage of this method was the utilization of l-serine as a cheap, stereoisomerically pure substrate. A steroid with a diamino system in the side chain was subjected to reaction with potassium tetrachloroplatinate to obtain the target platinum(II) complex. Attempts to synthesize similar diamine systems using the asymmetric Strecker reaction were unsuccessful.     

Preparation, characterization and application of a stationary chromatographic phase from a new (+)-tartaric acid derivative

The preparation, characterization and application of a new stationary phase derived from 1,4-cyclohexanedione and diethyl (+)-tartrate are described. A suitable TADDOL for immobilization has been synthesized and grafted to a γ-mercaptopropylsilylated silica gel. The resulting modified stationary phase has been characterized and its ability to separate enantiomers has been studied. While the free TADDOL in solution was able to resolve a range of enantiomers, the resolving properties were lost on immobilization. Solid state ¹³C CPMAS NMR of the new stationary phase was used to explain the lack of stereoselective recognition.     

Synthesis of a new stable conformationally constrained 2,7-anhydrosialic acid derivative

A stereoseletive synthesis of 2,7-anhydrosialic acid derivative 18 was achieved from d-glucono-delta-lactone. A highly syn-selective addition of Grignard reagent to theN-benzylimine 8 served as a key step.     

Westerdijkin A,a new hydroxyphenylacetic acid derivative from deep sea fungus Aspergillus westerdijkiae SCSIO 05233

A new methyl 2-(4-((2-hydroxy-3-methylbut-3-en-1-yl)oxy)phenyl) acetate 1, together with five known compounds 2–6, was isolated from the culture of the deep sea-derived fungus Aspergillus westerdijkiae SCSIO 05233. The new structure was determined by NMR (¹H and ¹³C NMR, HSQC, HMBC and MS) and optical rotation analysis. Compound 5 displayed weak inhibitory activities towards K562 and promyelocytic HL-60 with IC₅₀ values of 25.8 and 44.9 μM, and compound 6 showed strong antifouling activity with EC₅₀ value 8.81 μg/mL.     

(-)-Kunstleramide, a new antioxidant and cytotoxic dienamide from the bark of Beilschmiedia kunstleri gamble

A new dienamide, (2E,4E)-7-(3',4'-dimethoxyphenyl)-N-ethyl-6-(R)-hydroxyhepta- 2,4-dienamide, named (-)-kunstleramide (1), were isolated from the bark of Beilschmiedia kunstleri Gamble together with one neolignan: (+)-kunstlerone (2) and seven known alkaloids: (+)-nornuciferine (3), (-)-isocaryachine (4), (+)-cassythicine (5), (+)-laurotetanine (6), (+)-boldine (7), noratherosperminine (8), (+)-N-demethylphyllocaryptine (9). Their structures were established from spectroscopic techniques, most notably 1D- and 2D-NMR, UV, IR, OR, circular dichroism (CD) spectra and LCMS-IT-TOF. (-)-Kunstleramide (1) exhibited very poor dose-dependent inhibition of DPPH activity, with an IC?? value of 179.5 ± 4.4 μg/mL, but showed a moderate cytotoxic effect on MTT assays of A375, A549, HT-29, PC-3 and WRL-68 with EC?? values of 64.65, 44.74, 55.94, 73.87 and 70.95 μg/mL, respectively.     

Dendrocoumarin: a new benzocoumarin derivative from the stem of Dendrobium nobile

A new benzocoumarin derivative, dendrocoumarin (1), along with itolide A were isolated from the stems of Dendrobium nobile. The structure of the new compound 1 elucidated on the basis of NMR and mass spectroscopic data. Compounds 1 and 2 showed broad spectrum antibacterial activity against five terrestrial pathogenic bacteria.     

A new caffeoylgluconic acid derivative from the nearly ripe fruits of Evodia rutaecarpa

A new caffeoylgluconic acid derivative, trans-caffeoyl-6-O-d-gluconic acid methyl ester (1), together with two known compounds named trans-caffeoyl-6-O-d-glucono-γ-lactone (2) and trans-caffeoyl-6-O-d-gluconic acid (3), was isolated from the nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth.. These compounds were isolated by various separation methods associated with the UPLC-Q-TOF-MS technique. Their structures were elucidated on the basis of extensive spectroscopic methods.     

Essential Oil Composition of Beilschmiedia insignis from Malaysia

Chemistry of Natural Compounds -     

Pholiotone A,a new polyketide derivative from Pholiota sp

Abstract

Pholiotone A (1), a new polyketide derivative, with tetrahydrobenzofuran-4(2H)-one skeleton, together with four known compounds, trichodermatides A (2) and B (3) and koninginins B (4) and E (5), were isolated from the crude extract of Pholiota sp. The structures of all the isolated compounds were determined mainly by NMR experiments, the modified Mosher method and electronic circular dichroism (ECD) calculations. The antifungal and cytotoxicity of all isolates were evaluated.