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1.
Two new phlegmarane-type alkaloids, cermizines A (1) and B (2), three new quinolizidine alkaloids, cermizine C (3) and senepodines G (4) and H (5), and a new C16N2 type alkaloid consisting of a quinolizidine and a piperidine ring, cermizine D (6), as well as two new cernuane-type alkaloids, cernuine N-oxide (7) and lycocernuine N-oxide (8), have been isolated together with cernuine (9) and lycocernuine (10) from the club moss Lycopodium cernuum and L. chinense. The relative stereochemistry of 1-4 and 6, and the absolute stereochemistry of 5, 7, and 8 were elucidated by combination of NOESY correlations, modified Mosher's method, chemical transformations, and computational methods. Cermizine D (6) might be a biosynthetic intermediate of cernuane-type alkaloids such as 7-10. 相似文献
2.
Four new dimeric spiro-azaplilones, cochliodones A-D (1-4), two new azaphliones, chaetoviridines E and F (5 and 6), a new epi-chaetoviridin A (7), together with five known compounds, chaetoviridin A (8), ergosterol (9), chaetochalasin A (10), 24(R)-5α,8α-epidioxyergosta-6-22-diene-3β-ol (11), and ergosterol-β-d-glucoside (12) were isolated from the fungi Chaetomium cochliodes VTh01 and C. cochliodes CTh05. Structures and stereochemistry of the atropisomers 1-3 were determined by single-crystal X-ray diffraction analysis. Compounds 5, 10, and 11 exhibited antimalarial activity against Plasmodium falciparum, while 3, 5, 6, 10, and 11 showed antimycobacterial activity against Mycobacterium tuberculosis. In addition, 5 and 6 also showed cytotoxicity against the KB, BC1, and NCI-H187 cell lines. 相似文献
3.
In the present work, octachlorocyclotetraphosphazatetraene (1), N4P4Cl8, is reacted with aniline (2), 1-napthylamine (4) and 2-aminoanthracene (6) to give octakis(arylamino)cyclotetraphosphazenes (3, 5 and 7). These cyclotetraphosphazene compounds (3, 5 and 7) have been fully characterized by elemental analysis, mass (MS), FT-IR, 1H and 31P NMR spectroscopies. The molecular and crystal structures of 5 have been characterized by X-ray crystallography. The structure of 5 is monoclinic with the space group P21/c. The octakis(1-napthylamino)-(5) and octakis(2-aminoanthracene)-(7) cyclotetraphosphazene compounds have been synthesised for the first time in this study. The fluorescence properties of 3, 5 and 7 have been investigated in tetrahydrofuran (THF) and have been shown to have highly fluorescence behavior. This work also presents the quenching of arylamino substituted cyclotetraphosphazene derivatives (3, 5 and 7) by p-benzoquinone (BQ) or hydroquinone (HQ). 相似文献
4.
Both racemic ethyl 5-iodo-2-methylcyclohexanecarboxylate (1), known as Mediterranean fruit fly attractant ceralure B1, and its (−)-(1R,2R,5R) enantiomer 1a were conveniently synthesized from commercially available racemic trans-6-methyl-3-cyclohexenecarboxylic acid 2 or its (1R,6R) enantiomer 2a. Key steps included an asymmetric Diels-Alder reaction using a sultam auxiliary and cyclization of the unwanted trans-5-iodo-trans-2-methylcyclohexanecarboxylic acid (8) to the intermediate lactone 7 (or 8a to 7a). The new method may circumvent chromatographic separations and seems amenable to scale-up. 相似文献
5.
Jun-Wei He Zhen-Qiang Mu Hao Gao Guo-Dong Chen Qin Zhao Dan Hu Jing-Zu Sun Xiao-Xia Li Yan Li Xing-Zhong Liu Xin-Sheng Yao 《Tetrahedron》2014
Six new polyesters, talapolyesters A–F (1–4, 14, and 16), together with 11 known ones 15G256ν (5), 15G256ν-me (6), 15G256π (7), 15G256β-2 (8), 15G256α-2 (9), 15G256α-2-me (10), 15G256ι (11), 15G256β (12), 15G256α (13), 15G256α-1 (15), and 15G256ω (17), were isolated from the wetland soil-derived fungus Talaromyces flavus BYD07-13, and their structures were determined by NMR and MS spectroscopic data. Among them, 1–4 and 16 were assembled in a different manner from that of the known 256 polyesters. All the polyesters are composed of (R)-2,4-dihydroxy-6-(2-hydroxypropyl)benzoic acid and (R)-3-hydroxybutyric acid/(S)-3,4-dihydroxybutyric acid residues. The absolute configurations of the residues were determined by alkaline hydrolysis. The cytotoxicity against five tumor cell lines of these compounds was examined, and a tight structure–activity relationship is proposed. 相似文献
6.
Jian-Ping Zou Sheng-Lian Luo Ming-Jun Li Xin-Hua Tang Qiu-Ju Xing Qiang Peng Guo-Cong Guo 《Polyhedron》2010
A series of lanthanide(III) complexes with chelidamic acid ligand, [Ln(C7H2NO5)·3H2O]n·nH2O (Ln = La (1), Y (2), Sm (3), and Nd (4)), [Gd2(C7H2NO5)3·4H2O]n·2nH2O (5) and [Ce(C7H2NO5)·1.5H2O]n (6), have been synthesized by hydrothermal method and structurally characterized by single-crystal X-ray diffraction. Complexes 1–4 are isostructural and possess 2D framework. Complex 5 contains two different Gd(III) ions linked through carboxylate group to form a 2D framework. Complex 6 exhibits a (44) topology 2D network. The variable-temperature magnetic properties of 3 and 5 have been investigated. Furthermore, the photoluminescent properties of 1, 2, 3, and 5 at room temperature were also studied. 相似文献
7.
Ahmed M. Metwaly Frank R. Fronczek Guoyi Ma Hazem A. Kadry Atef A. El-Hela Abd-Elsalam I. Mohammad Stephen J. Cutler Samir A. Ross 《Tetrahedron letters》2014
Four new (1–4) and two known (5 and 6) α-pyrone derivatives have been isolated from Alternaria phragmospora, an endophytic fungus from Vinca rosea, leaves. The isolated compounds were chemically identified to be 5-butyl-4-methoxy-6-methyl-2H-pyran-2-one (1), 5-butyl-6-(hydroxymethyl)-4-methoxy-2H-pyran-2-one (2), 5-(1-hydroxybutyl)-4-methoxy-6-methyl-2H-pyran-2-one (3), 4-methoxy-6-methyl-5-(3-oxobutyl)-2H-pyran-2-one (4), 5-(2-hydroxyethyl)-4-methoxy-6-methyl-2H-pyran-2-one (5), and 5-[(2E)-but-2-en-1-yl]-4-methoxy-6-methyl-2H-pyran-2-one (6). Compounds 2 and 4 showed moderate antileukemic activities against HL60 cells with IC50 values of 2.2 and 0.9 μM and against K562 cells with IC50 values of 4.5 and 1.5 μM, respectively. 相似文献
8.
Maria C. Aversa Paola Bonaccorsi Cristina Faggi Assunta Marrocchi Aldo Taticchi 《Tetrahedron》2005,61(32):7719-7726
Cyclohexylsulfinyl-3-methyl-1,3-butadienes 5, 6, and 1-[1-(cyclohexylsulfinyl)ethenyl]cyclohexene (7), easily prepared from cyclohexanethiol (1) via transient cyclohexanesulfenic acid (4), were reacted with N-phenylmaleimide under different conditions, at normal and high pressure. The stereochemical outcome of these cycloadditions contributes a better understanding of the relationships among different factors controlling facial diastereoselection. 相似文献
9.
Tetsuro Ito Toshiyuki TanakaMunekazu Iinuma Ibrahim IliyaKen-ichi Nakaya Zulfiqar AliYoshikazu Takahashi Ryuichi SawaYoshiaki Shirataki Jin MurataDedy Darnaedi 《Tetrahedron》2003,59(28):5347-5363
Five new resveratrol oligomers; pauciflorols A-C (1-3), isovaticanols B (6) and C (8), and three new oligostilbene glucosides; pauciflorosides A (11), B (13), C (14), were isolated from the stem bark of Vatica pauciflora (Dipterocarpaceae) together with known 17 resveratrol oligomers (4, 5, 7, 9, 10, 12 and 15-25) and bergenin (26). The structures of isolates were established on the basis of detailed spectroscopic analysis. The typical and characteristic spectral properties of some resveratrol oligomers were also discussed. 相似文献
10.
From the aerial parts of Salvia castanea Diels f. tomentosa Stib., four new hemiketal germacranolide sesquiterpenoids, castanins C-F (1-4), were obtained as two pairs of interconvertible forms along with their acetates, 5 and 6. Their structures were elucidated by spectroscopic methods and X-ray analysis of the uninterconvertible isomeric acetates, 5 and 6. The computational study explained that the ratios of 1 and 2, 3 and 4, and their acetates (5 and 6) in the mixtures were 1:1, 1:2, and 1:3, respectively. In addition, the semisynthesis of castanins C (1) and D (2) was conducted by the photooxidation of castanin B (8), the major constituent of this plant. Compounds 5, 6, and 8 were also tested for their inhibitory activity toward MCF-7, HeLa, and HepG2 cell lines. 相似文献
11.
The singlet oxygen (1Δg) photooxidations of angelic acid salt (1), tiglic acid salt (2), 2,3-dimethyl-2-butenoic acid salt (3), 3-ethoxycarbonyl-5,6-dihydro-2-methyl-4H-pyrane acid salt (4), cis-3-hexenoic acid salt (5), and trans-3-hexenoic acid salt (6) were conducted in deuterated water. The major and minor ene allylic hydroperoxide products were quantified and indicate that the allylic hydrogen geminal to the carboxylate group is preferentially abstracted in 1-4, whereas the allylic hydrogen α to the carboxylate is slightly favored for 5 and 6. We have attributed the observed regiochemistry in 1-4 to stabilizing hydrogen bonding interactions between the solvent and the perepoxide, which leads to the major ene product. 相似文献
12.
Amnat Eamvijarn Nelson M. Gomes Tida Dethoup Jamrearn Buaruang Leka Manoch Artur Silva Madalena Pedro Ioulia Marini Vasilios Roussis Anake Kijjoa 《Tetrahedron》2013
Two new metabolites including a new aszonalenin analogue (1c) and a new meroditerpene (3) were isolated, together with aszonalenin (1a), acetylaszonalenin (1b), 13-oxofumitremorgin B (2), aszonapyrone A (4b) and helvolic acid, from the culture of the soil fungus Neosartorya fischeri (KUFC 6344). While the ethyl acetate extract of the culture of the diseased coral-derived fungus Neosartorya laciniosa (KUFC 7896) furnished aszonapyrone B (4a), aszonapyrone A (4b), tryptoquivaline L and 3′-(4-oxoquinazolin-3-yl) spiro[1H-indole-3,5′-oxolane]-2,2′-dione, the ethyl acetate extract of the culture of the marine sponge-associated fungus Neosartorya tsunodae (KUFC 9213) yielded a new analogue of chevalone C (5) and helvolic acid. The structures of the new compounds were established based on 1D and 2D NMR spectral analysis as well as HR-ESIMS. Compounds 1a–c, 2, 3, 4a, 4b and 5 were evaluated for their in vitro growth inhibitory activity on the MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer) and A375-C5 (melanoma) cell lines by the protein binding dye SRB method. 相似文献
13.
Nahoko Uchiyama Fumiyuki Kiuchi Gisho Honda Yoshio Takeda Ozodbek A. Ashurmetov 《Tetrahedron》2006,62(18):4355-4359
Trypanocidal constituents of Dracocephalum komarovi were investigated. Under guidance of the in vitro trypanocidal activity against epimastigotes of Trypanosoma cruzi, the causative agent of Chagas' disease, two new diterpenes, dracocequinones A (1) and B (2), and two known triterpene acids, ursonic acid and ursolic acid, were isolated as trypanocidal constituents, in addition to previously reported diterpenes, cyclocoulterone (4), komaroviquinone (5), dracocephalone A (6) and komarovispirone (7). Furthermore a new diterpene, komarovinone A (3), was isolated, together with four known terpenes. Among these compounds, komaroviquinone (5) showed the most potent activity with minimum lethal concentration of 0.4 μM. Structure elucidation of the new diterpenes 1-3 was described. 相似文献
14.
Victor M. Karpov 《Journal of fluorine chemistry》2007,128(7):714-717
The pyrolysis of 1,1-dichloroperfluorotetralin (4) in a stream of argon gives a mixture contained perfluoro-1-methyleneindan (1), perfluoro-3-methylindene (6), 1,1-dichloroperfluoroindan (2) and perfluoroindene (7), while copyrolysis of tetralin 4 with CHClF2 gives a mixture of compounds 1, 6 in the absence of compounds 2 and 7. 1-Chloro-2-(1-chloro-2,2-difluorovinyl)-3,4,5,6-tetrafluorobenzene (12) is formed in the pyrolysis of 1,1-dichloroperfluorobenzocyclobutene (5) in a stream of argon as well as in a stream of CHClF2. 相似文献
15.
Masahiko Isaka Arunrat Yangchum Kanokarn Kocharin Palangpon Kongsaeree Samran Prabpai 《Tetrahedron》2009,65(22):4396-475
Reinvestigation of the secondary metabolites from the marine mangrove fungus Aigialus parvus BCC 5311 led to the isolation of six new nonaketide metabolites, aigialomycins F (4) and G (5a/5b), 7′,8′-dihydroaigialospirol (7), 4′-deoxy-7′,8′-dihydroaigialospirol (8), and rearranged macrolides 9 and 10, along with six previously described compounds, hypothemycin (1), aigialomycins A (2) and B (3), aigialospirol (6), 4-O-demethylhypothemycin (11), and aigialone (12). The structures of the new compounds were elucidated by analyses of the NMR spectroscopic and mass spectrometry data in combination with chemical means. 相似文献
16.
Concomitant supplementation of a histone deacetylase inhibitor, suberoylanilide hydroxamic acid, and a DNA methyltransferase inhibitor, 5-azacytidine, to the culture medium of a plant endophytic fungus, Pestalotiopsis acaciae, dramatically altered its metabolic profiles. As a result, three novel aromatic compounds, 2′-hydroxy-6′-hydroxymethyl-4′-methylphenyl-2,6-dihydroxy-3-(2-isopentenyl)benzoate (1), 4,6-dihydroxy-7-hydroxymethyl-3-methylcoumarin (2) and 4,6-dihydroxy-3,7-dimethylcoumarin (3), were isolated, along with five known polyketides, endocrocin (4), pestalotiollide B (5), pestalotiopyrone G (6), scirpyrone A (7) and 7-hydroxy-2-(2-hydroxypropyl)-5-methylchromone (8). 相似文献
17.
Emilie V. Banide Helge Müller-Bunz Michael Casey M. Cristina Lagunas Michael J. McGlinchey 《Journal of organometallic chemistry》2008,693(10):1759-1770
Successive treatment of 9-(phenylethynyl)fluoren-9-ol (1a), with HBr, butyllithium and chlorodiphenylphosphine furnishes 3,3-(biphenyl-2,2′-diyl)-1-diphenylphosphino-1-phenylallene (5). Moreover, reaction of 1a directly with chlorodiphenylphosphine yields the corresponding allenylphosphine oxide (6). The allenylphosphine (5), and Fe2(CO)9 initially form the phosphine-Fe(CO)4 complex, 11, which is very thermally sensitive and readily loses a carbonyl ligand. In the resulting phosphine-Fe(CO)3 system, 12, the additional site at iron is coordinated by the allene double bond adjacent to phosphorus; the Fe(CO)3 tripod in 12 exhibits restricted rotation on the NMR time-scale even at room temperature. The corresponding chromium complex, (5)-Cr(CO)5 (9), has also been prepared. The gold complexes (5)-AuCl (13), and [(5)-Au(THT)]+ X−, where (THT) is tetrahydrothiophene, and X = PF6 (14a), or ClO4 (14b), are analogous to the known triphenylphosphine-gold complexes. In contrast, in the (arene)(allenylphosphine)RuCl2 system the allene double bond adjacent to phosphorus displaces a chloride, and the resulting cationic species undergoes nucleophilic attack by water yielding ultimately a five-membered Ru-P-CC-O ruthenacycle (17). Thus, the allenylphosphine (5), reacts initially as a conventional mono-phosphine but, when the metal centre has a readily displaceable ligand such as a carbonyl or halide, the allene double bond adjacent to the phosphorus can also function as a donor. X-ray crystal structures are reported for 5, 6, 11, 12, 13, 14a, 14b and 17. 相似文献
18.
Kazuhiro Sugamoto Yoh-ichi MatsusitaKana Matsui Chiaki KurogiTakanao Matsui 《Tetrahedron》2011,67(29):5346-5359
Chalcones bearing prenyl or geranyl groups from Angelica keiskei, such as 4-hydroxyderricin (1a), xanthoangelol (1e), xanthoangelol F (1f), xanthoangelol H (2), deoxyxanthoangelol H (3), and deoxydihydroxanthoangelol H (4) and their derivatives were synthesized. From the evaluation of antibacterial activity of the synthesized chalcones, 1a, isobavachalcone (1b), 1e, 1f, bavachalcone (5a), and broussochalcone B (5b) were found to inhibit Gram-positive bacteria. 相似文献
19.
New N-sulfonylpyrimidine derivatives 1-(p-toluenesulfonyl)uracil (1), 1-(p-toluenesulfonyl)thymine (2), 5-bromo-1-(p-toluenesulfonyl)uracil (3), 1-(methanesulfonyl)uracil (4), 1-(1-naphthylsulfonyl)uracil (5), and 1-(1-naphthylsulfonyl)thymine (6) were prepared by the condensation reaction of silylated pyrimidine derivatives with selected sulfonyl chlorides in acetonitrile. Some members of the series showed unexpected crystal properties as a consequence of their conformational chirality in the solid state. Compounds 1 and 5 exhibited chiral crystallization, which was, in the case of 1, accompanied by the formation of racemically twinned crystals regardless of the solvent used, while 5 gave a conglomerate of enantiomorphous crystals. For 2, 3, and 6, substituents at the C-5 position of the pyrimidine ring prevented chiral crystallization by influencing the crystal packing. Analysis of the crystal structures of 1, 4, and 5, reveals the influence of the arylsulfonyl group on the occurrence or absence of chiral crystallization. 相似文献
20.
Pyromellitic dianhydride (benzene-1,2,4,5-tetracarboxylic dianhydride) (1) was reacted with l-leucine (2) in a mixture of acetic acid and pyridine (3:2) and the resulting imide-acid [N,N′-(pyromellitoyl)-bis-l-leucine diacid] (4) was obtained in quantitative yield. The compound (4) was converted to the N,N′-(pyromellitoyl)-bis-l-leucine diacid chloride (5) by reaction with thionyl chloride. A new facile and rapid polycondensation reaction of this diacid chloride (5) with several aromatic diols such as phenol phthalein (6a), bisphenol-A (6b), 4,4′-hydroquinone (6c), 1,8-dihydroxyanthraquinone (6d), 1,5-dihydroxy naphthalene (6e), 4,4-dihydroxy biphenyl (6f), and 2,4-dihydroxyacetophenone (6g) was developed by using a domestic microwave oven in the presence of a small amount of a polar organic medium such as o-cresol. The polymerization reactions proceeded rapidly and are completed within 10 min, producing a series of optically active poly(ester-imide)s (PEIs) with good yield and moderate inherent viscosity of 0.10-0.27 dl/g. All of the above polymers were fully characterized by IR, elemental analyses and specific rotation. Some structural characterization and physical properties of these optically active PEIs are reported. 相似文献