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1.
The seven new triterpenoid saponins 1 – 7 were isolated from the roots of Gypsophila paniculata L. Their structures were established by 1D ‐ and 2D‐NMR techniques, HR‐MS, and acid hydrolysis. The isolated compounds include 3,28‐O‐bidesmosides with or without a 4‐methoxycinnamoyl group (see 1 vs. 2 and 3 ), and 3‐O‐monoglucosides 4 – 7 . All isolated saponins 1 – 7 and their aglycones were evaluated for their α‐glucosidase inhibition activity. Compound 1 showed inhibitory activity against yeast α‐glucosidase with an IC50 value of 100.9±3.3 μM , whereas compounds 2 – 7 were inactive. 相似文献
2.
You‐Min Ying Xiao‐Sa Liu Cui‐Ping Tong Jian‐Wei Wang Zha‐Jun Zhan Wei‐Guang Shan 《Helvetica chimica acta》2014,97(10):1433-1439
Three new lycopodium alkaloids, huperserramines A–C ( 1 – 3 , resp.), along with 15 known ones, lycopodine‐6α,11α‐diol ( 4 ), lycoposerramine H ( 5 ), lycoposerramine I ( 6 ), lycopodine‐6α‐ol ( 7 ), lycoposerramine M ( 8 ), diphaladine A ( 9 ), lycoposerramine K ( 10 ), lycoposerramine W ( 11 ), huperzine M ( 12 ), luciduline ( 13 ), phlegmariuine N ( 14 ), huperzine A ( 15 ), huperzine B ( 16 ), lycodine ( 17 ), and lycoposerramine R ( 18 ), were isolated from the whole plant of Huperzia serrata. Their structures were established by spectroscopic methods, including 2D‐NMR and MS analyses. All the isolates were evaluated for their inhibitory effects on acetylcholinesterase (AChE) and α‐glucosidase. As a result, lycopodine‐6α,11α‐diol ( 4 ) exhibited more potent α‐glucosidase inhibitory activity (IC50 148±5.5 μM ) than the positive control acarbose (IC50 376.3±2.7 μM ). 相似文献
3.
Yue Cong William Jia Jing Chen Shuang Song Jin‐Hui Wang Yu‐Hui Yang 《Helvetica chimica acta》2007,90(5):1038-1042
Two new steroidal alkaloids, neoverapatuline ( 1 ) and (1β,3α,5β)‐1,3‐dihydroxyjervanin‐12‐en‐11‐one ( 2 ), together with the four known compounds, veratramine ( 3 ), rubijervine ( 4 ), veratrosine ( 5 ), and veratroylzygadenine ( 6 ), were isolated from the roots and rhizomes of Veratrum nigrum L. Their structures were established through combined analyses of physicochemical properties and spectroscopic evidence. All compounds 1 – 6 were tested for their cytotoxicities in vitro against the human glioma cell line SF188. 相似文献
4.
Olapeju O. Aiyelaagbe Arvind S. Negi Abdulmumeen A. Hamid Suaib Luqman Sathish B. Kumar Fatima Kaneez 《中国化学会会志》2015,62(9):751-755
Methanol extract of Alafia barteri leaves showed cytotoxic activity on leukaemia carcinoma K562, and hepatic liver cancer cells WRL (IC50 values 193.1 and 225.0 μM respectively). Isolation of the extract gave ursane triterpenoid, 28‐acety‐urs‐5,20‐dien‐2β,3β,24α‐triol, 1 , together with undecanol, 2 , stigmasterol, 3 and octadecanoic acid, 4 . The structures of these compounds were identified by spectroscopic analysis, including MS, 1D and 2D NMR, and supported with literature data. Compound 1 exhibited cytotoxic activity against K‐562 at 50 and 100 μM concentrations with IC50 74.22 μM, while compounds 2 , 3 and 4 showed low inhibition of WRL, MCF‐7 and COLO cell lines. 相似文献
5.
Hao Gao Kui Hong Guo‐Dong Chen Chuan‐Xi Wang Jin‐Shan Tang Yang Yu Miao‐Miao Jiang Man‐Mei Li Nai‐Li Wang Xin‐Sheng Yao 《Magnetic resonance in chemistry : MRC》2010,48(1):38-43
Two new oxidized sterols 1 and 2 were obtained from the active fraction of a mangrove fungus Aspergillus awamori isolated from the soils around the mangrove plant Acrostichum speciosum. Their structures were elucidated using spectroscopic methods as 22E‐7α‐methoxy‐5α,6α‐epoxyergosta‐8(14),22‐dien‐3β‐ol (1) and 22E‐3β‐hydroxy‐5α,6α,8α,14α‐diepoxyergosta‐22‐en‐7‐one (2). The NMR data and complete assignments for both DMSO‐d6 and CDCl3 were given. Their cytotoxic activity against A549 cell line was evaluated. Furthermore, the detailed conformation analysis for ring B (cyclohexene oxide system) of sterol 1 was given on the basis of NOEs. The endo‐boat conformation was considered as the preferred conformation for ring B rather than half‐chair conformation. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
6.
Claudia Villanueva‐Cañongo Nury Pérez‐Hernández Beatriz Hernández‐Carlos Ernestina Cedillo‐Portugal Pedro Joseph‐Nathan Eleuterio Burgueño‐Tapia 《Magnetic resonance in chemistry : MRC》2014,52(5):251-257
Chemical investigation of the aerial parts of Senecio polypodioides lead to the isolation of the new eudesmanoid 1β‐angeloyloxyeudesm‐7‐ene‐4β,9α‐diol ( 1 ) and the known dirhamnosyl flavonoid lespidin ( 3 ), while from roots, the known 7β‐angeloyloxy‐1‐methylene‐8α‐pyrrolizidine ( 5 ) and sarracine N‐oxide ( 6 ), as well as the new neosarracine N‐oxide ( 8 ), were obtained. The structure of 1 and 8 was elucidated by spectral means. Complete assignments of the 1H NMR data for 5 , 6 , sarracine ( 7 ), and 8 were made using one‐dimensional and two‐dimensional NMR experiments and by application of the iterative full spin analysis of the PERCH NMR software. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
7.
Andreas Bertogg Lukas Hintermann Dominique P. Huber Mauro Perseghini Maria Sanna Antonio Togni 《Helvetica chimica acta》2012,95(3):353-403
The substrate range of the [TiCl2(TADDOLate)] (TADDOL=α,α,α′,α′‐tetraaryl‐1,3‐dioxolane‐4,5‐dimethanol)‐catalyzed asymmetric α‐fluorination of activated β‐carbonyl compounds has been investigated. Optimal conditions for catalysis are characterized by using 5 mol‐% of TiCl2(naphthalen‐1‐yl)‐TADDOLate) as catalyst in a saturated (0.14 mol/l) MeCN solution of F‐TEDA (1‐(chloromethyl)‐4‐fluoro‐1,4‐diazoniabicyclo[2.2.2]octane bis‐[tetrafluoroborate]) at room temperature. A series of α‐methylated β‐keto esters (3‐oxobutanoates, 3‐oxopentanoates) with bulky benzyl ester groups (60–90% ee) or phenyl ester (67–88% ee) have been fluorinated readily, whereas α‐acyl lactones were also readily fluorinated, but gave lower inductions (13–46% ee). Double stereochemical differentiation in β‐keto esters with chiral ester groups raised the stereoselectivity to a diastereomeric ratio (dr) of up to 96.5 : 3.5. For the first time, β‐keto S‐thioesters were asymmetrically fluorinated (62–91.5% ee) and chlorinated (83% ee). Lower inductions were observed in fluorinations of 1,3‐diketones (up to 40% ee) and β‐keto amides (up to 59% ee). General strategies for preparing activated β‐carbonyl compounds as important model substrates for asymmetric catalytic α‐functionalizations are presented (>60 examples). 相似文献
8.
Xanthones with α‐Glucosidase Inhibitory Activities from Aspergillus versicolor,a Fungal Endophyte of Huperzia serrata
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Tian‐Tian Ma Wei‐Guang Shan You‐Min Ying Lie‐Feng Ma Wen‐Hong Liu Zha‐Jun Zhan 《Helvetica chimica acta》2015,98(1):148-152
Three new xanthones, namely huperxanthones A–C ( 1 – 3 , resp.), were obtained from the cultures of Aspergillus versicolor, a fungal endophyte of Huperzia serrata, together with 1,7‐dihydroxy‐8‐(methoxycarbonyl)xanthone‐3‐carboxylic acid ( 4 ), β‐diversonolic acid methyl ester ( 5 ), 4‐hydroxyvertixanthone ( 6 ), and sydowinin B ( 7 ). The structures of the new compounds were established by detailed NMR and MS analysis, especially by 2D‐NMR experiments. All xanthones were evaluated for their effects on α‐glucosidase. Compound 4 exhibited a potent inhibitory activity against α‐glucosidase with an IC50 value of 0.24 mM (vs. 0.38 mM for acarbose). The rest of the compounds showed weak or no activity against α‐glucosidase. 相似文献
9.
Concise Synthesis and Antidiabetic Effect of Three Natural Triterpenoid Saponins Isolated from Fadogia ancylantha (Makoni tea)
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The first concise synthesis of the bidesmosidic oleanolic acid saponins 1 – 3 isolated from Fadogia ancylantha (Makoni tea) have been accomplished through a ‘one‐pot sequential glycosylation’ strategy with two glycosyl 1‐(trichloroacetimidate)s as glycosyl donors. The synthesized natural products 1 – 3 were then evaluated for their inhibitory activities against α‐glucosidase, α‐amylase, and lipase. Among the assayed compounds 1 – 3 , compound 1 showed strong α‐glucosidase and α‐amylase inhibition, with IC50 values of 160 and 180 μM , respectively. Moreover, compounds 2 and 3 showed strong inhibition against α‐glucosidase and lipase, with the respective IC50 values of 170 and 190 μM , and 190 and 200 μM . 相似文献
10.
Surjeet Verma Shiv Kumar Santosh Kumar Srivastava Mahendra P. Darokar 《中国化学会会志》2014,61(10):1121-1126
A new clionasterol glucoside, clionasterol‐[(1'→3α)‐O‐β‐D]‐glucopyranoside ( 1 ), a new acylated clionasterol glucoside, clionasterol‐[6'‐O‐acyl‐(1'→3β)‐O‐b‐D]‐glucopyranoside ( 2 ) and clionasterol ( 3 ) were isolated from the aerial parts of Oplismenus burmannii. The nature and length of fatty acid acyl chains in 2 was identified by alkaline methanolysis of compound 2 . The aglycone fraction on GC‐MS analysis showed three peaks in GC at tR 49.86 (82.1%), 51.13 (13.3%) and 56.53 (4.6%) min, which were characterized as arachidic acid methyl ester ( a ) oleic acid methyl ester ( b ) and 12‐methyltetradecanoic acid methyl ester ( c ) respectively. Thus 2 was characterized as a mixture of three new compounds, clionasterol‐[6'‐O‐eicosanoyl‐(1'→3β)‐O‐β‐D]‐glucopyranoside ( 2a ), clionasterol‐[6'‐O‐(8Z)‐octa‐deca‐9‐enoyl‐(1'→3β)‐O‐β‐D]‐glucopyranoside ( 2b ) and clionasterol‐[6'‐O‐(12‐methyltetradecanoyl)‐(1'→3β)‐O‐β‐D]‐glucopyranoside ( 2c ). 相似文献
11.
Yi‐Feng Lü Ke‐Yu Chen Hui‐Liang Li Yue‐Hu Pei Run‐Hui Liu Wei‐Dong Zhang 《Helvetica chimica acta》2008,91(5):819-824
Biotransformation of vermitaline ( 1 ) by Cunninghamella echinulata (ACCC 30369) was carried out. Four biotransformation products were obtained and three of them were characterized as new compounds. On the basis of their NMR and mass‐spectral data, their structures were characterized as 7α‐hydroxyrubijervine ( 2 ), 7α‐hydroxyrubijervine‐7‐O‐β‐D ‐galactofuranoside ( 3 ), 7α‐hydroxyvermitaline ( 4 ), and 7α‐hydroxyvermitaline‐7‐O‐β‐D ‐galactofuranoside ( 5 ). 相似文献
12.
Laurent Dufossé Dominique Cartier Benoist Valla Mireille Fouillaud Roger Labia Alain Valla 《Helvetica chimica acta》2013,96(2):259-265
Catalytic base‐induced decarboxylation of polyunsaturated α‐cyano‐β‐methyl acids derived from malonic acid led to the corresponding nitriles 3 (Schemes 2 and 3), 6 (Scheme 5), and 9 (Scheme 6). This decarboxylation occurred with previous deconjugation of the α,β‐alkene moiety of the α‐cyano‐β‐methyl acid, leading to an α‐cyano‐β‐methylene propanoic acid which was easily decarboxylated (see Scheme 2). β‐Methylene intermediates, in some cases, could be isolated; mechanistic pathways are proposed. The nitriles 3, 6 , and 9 were reduced to the sesquiterpene aldehydes 4 (β‐end group), 7 (φ‐end group), and 10 (ψ‐end group), respectively. 相似文献
13.
A Ph3P‐catalyzed cyclization of α‐halogeno ketones 2 with dialkyl acetylenedicarboxylates (=dialkyl but‐2‐ynedioates) 3 produced halogenated α,β‐unsaturated γ‐butyrolactone derivatives 4 in good yields (Scheme 1, Table). The presence of electron‐withdrawing groups such as halogen atoms at the α‐position of the ketones was necessary in this reaction. Cyclization of α‐chloro ketones resulted in higher yields than that of the corresponding α‐bromo ketones. Dihalogeno ketones similarly afforded the expected γ‐butyrolactone derivatives in high yields. 相似文献
14.
Shinsuke Inagaki Sayuri Taniguchi Haruo Hirashima Tatsuya Higashi Jun Zhe Min Ruri Kikura‐Hanajiri Yukihiro Goda Toshimasa Toyo'oka 《Journal of separation science》2010,33(20):3137-3143
Enantioseparation of α,α‐diphenyl‐2‐pyrrolidinemethanol (D2PM) and methylphenidate (MPH; Ritalin®) using (R)‐(?)‐4‐(N,N‐dimethylaminosulfonyl)‐7‐(3‐isothiocyanatopyrrolidin‐1‐yl)‐2,1,3‐benzoxadiazole as the chiral derivatization reagent has been achieved for the first time, and a simple, reliable detection method using HPLC with fluorescence detection has been developed. D2PM and MPH have been derivatized with (R)‐(?)‐4‐(N,N‐dimethylaminosulfonyl)‐7‐(3‐isothiocyanatopyrrolidin‐1‐yl)‐2,1,3‐benzoxadiazole at 55°C for 15 min. The derivatives of D2PM and MPH have been separated, completely and rapidly, using a reversed‐phase system within 16 min (resolution factor (Rs)=1.60 and 2.53, respectively). The detection limits of (R)‐ and (S)‐D2PM were found to be 6.8 and 13 ng/mL, respectively, and those of D ‐ and L ‐threo‐MPH were 61 and 66 ng/mL, respectively (S/N=3). The proposed method was successfully applied to the analysis of rat plasma, where the rats were separately dosed with D2PM and MPH (Ritalin). 相似文献
15.
A series of chalcone ligands and their corresponding vanadyl complexes of composition [VO (LI–IV)2(H2O)2]SO4 (where LI = 1,3‐Diphenylprop‐2‐en‐1‐one, LII = 3‐(2‐Hydroxy‐phenyl)‐1‐phenyl‐propenone, LIII = 3‐(3‐Nitro‐phenyl)‐1‐phenyl‐propenone, LIV = 3‐(4‐Methoxy‐phenyl)‐1‐phenyl‐propenone) have been synthesized and characterized using various spectroscopic (Fourier‐transform infrared, electrospray ionization mass, nuclear magnetic resonance, electron paramagnetic resonance, thermogravimetric analysis, vibrating sample magnetometer) and physico‐analytic techniques. Antidiabetic activities of synthesized complexes along with chalcones were evaluated by performing in vitro and in silico α‐amylase and α‐glucosidase inhibition studies. The obtained results displayed moderate to significant inhibition activity against both the enzymes by vanadyl chalcone complexes. The most potent complexes were further investigated for the enzyme kinetic studies and displayed the mixed inhibition for both the enzymes. Further, antioxidant activity of vanadyl chalcone complexes was evaluated for their efficiency to release oxidative stress using 2,2‐diphenyl‐1‐picryl‐hydrazyl‐hydrate assay, and two complexes (Complexes 2 and 4 ) have demonstrated remarkable antioxidant activity. All the complexes were found to possess promising antidiabetic and antioxidant potential. 相似文献
16.
Synthesis of Phenanthrene Derivatives through the Reaction of an α,α‐Dicyanoolefin with α,β‐Unsaturated Carbonyl Compounds
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Abdolali Alizadeh Seyed Yasub Hosseini Hadi Sedighian Fahimeh Bayat 《Helvetica chimica acta》2015,98(10):1426-1434
Phenanthrene derivatives were prepared by reacting an α,α‐dicyanoolefin with different α,β‐unsaturated carbonyl compounds resulting from Wittig reaction of ninhydrin and phosphanylidene or condensation of barbituric acid and an aldehyde. The easy procedure, mild and metal‐catalyst free, reaction conditions, good yields, and no need for chromatographic purifications are important features of this protocol. The structures of the product of type 3 and 5 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS). A plausible mechanism for this type of reaction is proposed (Scheme 1). 相似文献
17.
Zhengyue Ma Xinghua Zhang Shikui Wang Yang He Gengliang Yang Beilei Li Junjie Yang Yuejuan Lu Jiewei Sun 《中国化学》2011,29(4):757-764
As epoxy functional group has high anticancer activity, α,β‐epoxyketones were designed and synthesized as new anticancer agents, and their structures were confirmed by UV, 1H NMR, IR, MS technigeces and elemental analysis. Their in vitro anticancer activities were evaluated by MTT method and the results showed that the compound 4c exhibited good activity with IC50 of 17.8, 22.0 and 24.1 µg/mL against A‐549, Hela and HepG2 cells, respectively. The dose of LD50 of the mice by intragastric administration was 1864.4 mg/kg. Therefore, the α,β‐epoxyketones could potentially provide as new anticancer agents. 相似文献
18.
The synthesis of 3,4‐didehydroionone isomers 4 , (+)‐ 6 , and (?)‐ 6 and of 3,4‐didehydro‐7,8‐dihydroionone isomers 5 , (+)‐ 7 , and (?)‐ 7 was accomplished starting from commercially available racemic α‐ionone ( 1 ). Their preparation of the racemic forms 4 – 7 was first achieved by mean of a number of chemo‐ and regioselective reactions (Schemes 1 and 2). The enantio‐ and diastereoselective lipase‐mediated kinetic acetylation of 4‐hydroxy‐γ‐ionone ( 10a / 10b ) provided 4‐hydroxy‐γ‐ionone (+)‐ 10a /(±)‐ 10b and (+)‐4‐(acetyloxy)‐γ‐ionone ((+) 12b ) (Scheme 3). The latter compounds were used as starting materials to prepare the 3,4‐didehydro‐γ‐ionones (+)‐ and (?)‐ 6 and the 3,4‐didehydro‐7,8‐dihydro‐γ‐ionones (+)‐ and (?)‐ 7 in enantiomer‐enriched form. The absolute configuration of (+)‐ 12b was determine by chemical correlation with (+)‐(6S)‐γ‐ionone ((+)‐ 3 ) and with (?)‐(6S)‐α‐ionone ((?)‐ 1 ) therefore allowing to assign the (S)‐configuration to (+)‐ 6 and (+)‐ 7 . Olfactory evaluation of the above described 3,4‐didehydroionone isomers shows a significant difference between the enantiomers and regioisomers both in fragrance feature and in detection threshold (Table). 相似文献
19.
Xiaonong Chen Eli Ruckenstein 《Journal of polymer science. Part A, Polymer chemistry》2000,38(9):1662-1672
Alkali and earth‐alkali salts of dicyclopentadiene dicarboxylic acid (DCPDCA) were prepared and employed as monomers in the polyesterification with an α,ω‐dihalide monomer, such as 1,4‐dichlorobutane (DCB), 1,4‐dibromobutane (DBB), α,α′‐dichloro‐p‐xylene (DCX), and α,α′‐dibromo‐p‐xylene (DBX). Novel linear polymers that possessed repeating moieties of dicyclopentadiene ( DCPD ) in the backbone were thus prepared. The IR and NMR spectra indicated that poly(tetramethylene dicyclopentadiene dicarboxylate) (PTMDD) with a number‐average molecular weight (Mn ) of about 1× 104 and poly(p‐xylene dicyclopentadiene dicarboxylate) (PXDD) with a Mn of 4–6 × 103 were obtained with an yield of about 80% via the polyesterification of the alkali salts with DBB and DCX, respectively. The reaction was carried out in the presence of a phase transfer catalyst, such as BzMe3NBr or poly(ethylene glycol), in DMF at 100 °C for 4 h. Oligomers with a lower Mn (1–2 × 103) were obtained when the earth‐alkali salts were employed as salt monomers. Compared to the irreversible linear polymers, poly(p‐xylene terephthalate) (PXTP) and poly(p‐xylene maleate) (PXM), prepared through the reaction between DCX and the potassium salts of terephthalic and maleic acid, respectively, the specific viscosities (ηsp) of the new linear polymers increased abnormally with the decrease of the temperature from 200 °C to 100 °C. This occurred due to the thermally reversible dedimerization/redimerization of DCPD moieties of the backbone of the polymers via the catalyst‐free Diels–Alder/retro Diels–Alder cycloadditive reactions. The ratio of the ηsp at 100 °C and 200 °C of the reversible polymers was found to be much higher than that of PXTP and PXM, even when the heating/cooling cycle was carried out several times under a N2 atmosphere. The obtained results indicated that thermally reversible covalently bonded linear polymer can be obtained by introducing the DCPD structure into the backbone of the polymer through the polymerization of a monomer containing the DCPD moiety. The reversible natures of the polymers and oligomers might be useful in preparing easily processable and recyclable polymers and thermosensor materials. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1662–1672, 2000 相似文献
20.
A general atom‐economical approach for the synthesis of α‐halomethyl ketones is demonstrated through Ce(SO4)2/acid co‐catalyzed hydration of a wide range of haloalkynes. The reactions are conducted under convenient conditions and provide products with excellent regioselectivity in good to excellent yields, with broad substrate scope. This protocol is an alternative to conventional α‐halogenation of ketones. 相似文献