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1.
Werner?Seebacher Reto?Brun Robert?Saf Robert?WeisEmail author 《Monatshefte für Chemie / Chemical Monthly》2003,134(10):1411-1420
Summary. 4-Aminobicyclo[2.2.2]octanones were converted to their N-oxides and to 4-aminobicyclo[2.2.2]octanes. Furthermore, the 6,7-bis-(4-methoxyphenyl) analogues were synthesized. All products were screened for their activities against Trypanosoma b. rhodesiense and Plasmodium falciparum. The pharmacological results were compared with those of formerly tested bicyclo[2.2.2]octanones and bicyclo[2.2.2]octanols. Structure-activity relationships are discussed.Received April 8, 2003; accepted April 14, 2003
Published online September 25, 2003 相似文献
2.
Two compounds janoxepin (1) and brevicompanine B (2) were isolated from the fungus Aspergillus janus and the structures elucidated by one- and two-dimensional NMR spectroscopic methods and mass spectrometry. Janoxepin is a novel oxepin derivative with a rare d-leucine incorporated. Brevicompanine B has previously only been isolated from Penicillium brevicompactum. Both compounds were tested in antimicrobial assays and found to be active against the malaria parasite Plasmodium falciparum 3D7 (IC50-values of 28 and 35 mg/ml, respectively). However, no activity was observed in antifungal or antibacterial assays. 相似文献
3.
Takeshi Kodama Shingo AokiSeiho Kikuchi Tomoki MatsuoYoshimitsu Tachi Keisuke NishikawaYoshiki Morimoto 《Tetrahedron letters》2013
The first concise total synthesis of C2 symmetric (+)-ekeberin D4 (1) that exhibits antiplasmodial activity has been achieved in total nine steps and 27% yield from the known diol 4. The efficient synthetic method features the regio- and diastereoselective epoxidation of 4 and convergent coupling between half fragments 2 and 3 by taking into account the C2 symmetric property. 相似文献
4.
Securines A—E, three dimeric diarymethane derivatives ( 1 — 3 ) and two enantiomeric diarymethane derivative monomers ( 4 and 5 ), were isolated and characterized from the medicinal plant Securidaca inappendiculata. Compounds 1 and 2 are a pair of enantiomeric diarymethane derivative dimers, and compound 3 is a mesomeric diarymethane derivative dimer. Their structures were determined by a combination of spectroscopic data, X‐ray crystallography, electronic circular dichroism (ECD) analysis, and computational ECD calculations. Dimeric compounds 1 — 3 showed moderate antiplasmodial activities with IC50 values of 0.9, 1.4, and 1.5 μM, respectively. 相似文献
5.
Two 2,6‐Dioxabicyclo[3.3.1]nonan‐3‐ones from Phragmanthera capitata (Spreng.) Balle (Loranthaceae)
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Bruno N. Lenta Joél T. Ateba Jean R. Chouna Makoah N. Aminake Flore Nardella Gabriele Pradel Beate Neumann Hans Georg Stammler Catherine Vonthron‐Sénécheau Silvère Ngouela Norbert Sewald 《Helvetica chimica acta》2015,98(7):945-952
Phytochemical investigation of the leaves of Phragmanthera capitata collected on Cassia spectabilis tree led to the isolation of two natural lactones, rel‐(1R,5S,7S)‐7‐[2‐(4‐hydroxyphenyl)ethyl]‐2,6‐dioxabicyclo[3.3.1]nonan‐3‐one ( 1 ) and 4‐{2‐[rel‐(1R,3R,5S)‐7‐oxo‐2,6‐dioxabicyclo[3.3.1]non‐3‐yl]ethyl}phenyl 3,4,5‐trihydroxybenzoate ( 2 ) together with the known compounds betulinic acid ( 3 ), dodoneine ( 4 ), quercetin 3‐O‐α‐L ‐rhamnopyranoside ( 5 ), quercetin 3‐O‐α‐L ‐arabinofuranoside ( 6 ), quercetin ( 7 ), betulin ( 8 ), lupeol ( 9 ), and sitosterol ( 10 ). Their structures were established by means of modern spectroscopic techniques, and the relative configuration of compound 1 was confirmed by X‐ray analysis. Compounds 1 and 2 were tested in vitro for their antiplasmodial activity against the Plasmodium falciparum chloroquine sensitive‐strains NF54 and 3D7. Compound 2 exhibited good antiplasmodial activity against both strains with IC50 of 2.4 and 4.9 μM , respectively, while compound 1 was inactive. 相似文献
6.
Diah Anggraini Wulandari Elizabeth Sidhartha Iriani Setyaningsih Jonathan Marshall Marbun Din Syafruddin 《Natural product research》2018,32(17):2067-2070
The rapid emergence of antimalarial drug resistance necessitates a continual effort on novel drug discovery. A cyanobacterium, Spirulina platensis, is a potential antimalarial agent that has been widely consumed as food supplement in the form of crude extract. It is known to possess antiviral, antibacterial and antifungi activities. This study examined the antimalarial activities of several Spirulina formulas against Plasmodium falciparum 3D7, in vitro. The tested Spirulina formulas included commercially available capsule, crude extract and alkaloid fraction. Results showed that all tested formula possessed antimalarial activities with the Spirulina capsule exhibited the highest activities (IC50 = 2.16 μg/mL). Light and electron microscopies revealed interference of the Spirulina with the parasite hemozoin formation. In conclusion, all tested Spirulina formulas and fraction exhibited moderate to high antimalarial activities. 相似文献
7.
Werner?SeebacherEmail author Marcel?Kaiser Reto?Brun Robert?Saf Robert?Weis 《Monatshefte für Chemie / Chemical Monthly》2005,136(4):625-634
Summary. The synthesis of new bicyclo[2.2.2]octane derivatives is described and their structures were established by NMR experiments. All compounds were tested in in vitro assays for their activities against causative organisms of malaria and African sleeping sickness and compared to those of former synthesized compounds. 相似文献
8.
Gustav Komlaga Grégory Genta-Jouve Sandrine Cojean Rita A. Dickson Merlin L.K. Mensah Philippe M. Loiseau Pierre Champy Mehdi A. Beniddir 《Tetrahedron letters》2017,58(38):3754-3756
The chemical investigation of the antimalarial plant Phyllanthus fraternus G. L. Webster (Phyllanthaceae) resulted in the discovery of the Securinega alkaloid (+)-allonorsecurinine (1), previously reported as a synthetic compound, together with the known ent-norsecurinine (2), nirurine (3), bubbialine (4), epibubbialine (5) and the lignan phyllanthin (6). The structure and absolute configuration of the new compound were elucidated on the basis of extensive spectroscopic analysis, optical rotation, and GIAO NMR shift calculation followed by CP3 analysis. The antiplasmodial activity of these compounds was evaluated against chloroquine-resistant (W2) and -sensitive (3D7) strains of Plasmodium falciparum. Among them, ent-norsecurinine (2) and (+)-allonorsecurinine (1) showed the strongest activity (IC50: 1.14 ± 0.32 and 2.57 ± 0.53 µM) respectively, against W2 but one of the weakest against 3D7. 相似文献
9.
Lorena S.R. Martelli Lucas C.C. Vieira Márcio W. Paixão Julio Zukerman-Schpector Juliana O. de Souza Anna Caroline C. Aguiar Glaucius Oliva Rafael V.C. Guido Arlene G. Corrêa 《Tetrahedron》2019,75(25):3530-3542
The organocatalysed asymmetric vinylogous Michael addition of α,α-dicyanoolefins to α,β-unsaturated aldehydes and ketones have been reported in the last decade, however, chalcones have been poorly explored. Moreover, a considerable part of the publications in this theme still employs undesirable solvents, such as toluene and THF, with concerns related to health and environmental safety. We report herein the use of a bifunctional catalyst derived from a Cinchona alkaloid to perform the enantio- and diastereoselective Michael addition of α,α-dicyanoolefins to chalcones using 2-MeTHF as solvent. The Michael adducts were obtained in moderate to good yields and were evaluated for their antiplasmodial and cytotoxic activity. 相似文献
10.
J. N. Lisgarten B. S. Potter R. A. Palmer James E. Pitts C. W. Wright 《Journal of chemical crystallography》2008,38(11):815-819
Abstract The structure of C16H10N4O4[HCl,1.5CH3OH], Mr = 406.80, has been determined from X-ray diffraction data. The crystals are monoclinic, space group C2/c, with eight molecules
per unit cell and a = 21.482(4), b = 7.131(1), c = 24.495(5) ?, β = 111.01(3)°, crystal density Dc = 1.546 g/cm3. The material was difficult to crystallize and crystals produced were found to be poor diffractors. Intensity data were measured
at liquid nitrogen temperature using a weakly diffracting crystal typical of the batch. However the X-ray analysis has finally
enabled the chemical constitution of this cryptolepine derivative, which was previously incorrectly assigned, to be unequivocally
established. Direct methods were used to solve the structure which was refined by full-matrix least squares to a conventional
R-index of 0.0798 for 2,861 reflections and 268 parameters. The 7,9-dinitrocryptolepine molecule is highly planar with a strong
intramolecular hydrogen bond between N(10) in ring C and O(92) of a nitro group. There are a number of intermolecular hydrogen
bonds involving the cryptolepine derivative the hydrochloride and both solvated methanols. One of the methanol solvate molecules
(methanol 2) is unusually disordered with its C atom lying exactly on a crystallographic twofold axis. Consequently the methanol
OH and H3 groups are at 0.5 occupancy and repeated by the twofold symmetry.
Graphical Abstract Cryptolepine (5-methyl, 10H-indolo[3,2-b]quinoline) the principal constituent of Cryptolepis sanguinolenta (Periplocaceae) is currently of interest as a lead compound for the development of both antimalarial and anticancer agents.
Cryptolepine has potent activity against malaria parasites in vitro, but it is also cytotoxic on account of its abilities
to intercalate into DNA, inhibit DNA synthesis and inhibit topoisomerase II. The 7,9-dinitroanalogue of cryptolepine was synthesised
as part of a program designed to discover new antimalarial and anticancer agents. The X-ray structure of this compound will
help to determine whether or not 7,9-dinitrocryptolepine is able to intercalate into DNA and facilitate the design of new
cryptolepine analogues with DNA binding properties appropriate for antimalarial (with no DNA intercalation) or anticancer
(sequence-specific binding) applications.
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