排序方式: 共有21条查询结果,搜索用时 15 毫秒
1.
Xia Cheng Guoliang Zhang Raina Seupel Doris Feineis Daniela Brünnert Manik Chatterjee Andreas Schlosser Gerhard Bringmann 《Tetrahedron》2018,74(38):5102-5112
Epoxide 2b is an analog of the synthetic intermediate 2a en route to the polyketide-derived antitumoral naphthoquinone dioncoquinone B (1), isolated from cell cultures of the tropical liana Triphyophyllum peltatum (Dioncophyllaceae). Compound 2b was found to induce strong apoptosis in multiple myeloma cells at a concentration (EC50?=?3.5?μM), distinctly lower than that of 1 and any related analog, without exerting significant toxicity against normal blood cells. Preliminary studies showed that 2b follows different SAR rules as compared to the naphthoquinones. Among the series of synthesized epoxides, 2b was the most active one and was thus, after biotinylation, subjected to mass spectrometry-based affinity capture experiments aiming at the identification of target proteins. The MS data revealed 2b to address proteins that are associated with stress regulation processes which are critical for multiple myeloma cell survival. 相似文献
2.
Markus Ganzera Ivo Nischang Christian Siegl Birgit Senzenberger Frantisek Svec Hermann Stuppner 《Electrophoresis》2009,30(21):3757-3763
Two microscale separation techniques for the analysis of bioactive naphthoquinones in Eleutherine americana were developed and validated. By MEKC four compounds (eleuthoside B, isoeleutherin, eleutherol and eleutherinoside A) could be determined in plant extracts using an aqueous electrolyte solution composed of 25 mM sodium tetraborate, 50 mM sodium cholate and 20% THF. CEC on a polymeric methacrylate‐based monolith with strong cationic properties showed promising results, as it additionally enabled the separation of two enantiomers, eleutherin and isoeleutherin. The mobile phase for CEC experiments comprised 3 mM ammonium formate in a mixture of ACN and water. At an applied voltage of ?25 kV, all five markers were baseline separated in less than 12 min. Both methods were successfully validated for linearity (MEKC: R2≥0.999; CEC: R2≥0.997), sensitivity (MEKC: LOD=4–5 μg/mL; CEC: LOD=2–8 μg/mL), accuracy (MEKC: 96.5–102.7% recovery; CEC: 97.1–103.5% recovery) and precision (MEKC: σrel≤2.43%; CEC: σrel≤2.21%). The quantitative analysis of naphthoquinone derivatives in several E. americana samples showed that both methods are suitable for practical applications, because the results were well comparable to those obtained by established techniques such as HPLC. 相似文献
3.
In this paper, we present our preliminary studies into naphthoquinones as novel reagents for the detection of latent fingermarks on paper. Latent fingermarks deposited on paper substrates were treated with solutions of selected naphthoquinones in ethyl acetate/HFE-7100, with subsequent heating. The selected compounds were 1,4-dihydroxy-2-naphthoic acid, 1,2-naphthoquinone-4-sulfonate, 2-methoxy-1,4-naphthoquinone and 2-methyl-1,4-naphthoquinone. All of the tested compounds yielded purple-brown visible fingermarks, which also exhibited photoluminescence when illuminated with a high intensity filtered light source at 555 nm and viewed through red goggles. Indirect heat using an oven at 150 °C for 1 h was found to be superior to direct heat with an iron, which while providing faster development lead to increased levels of background colouration. Luminescence spectrophotometry revealed differences in photoluminescence characteristics for fingermarks developed with the different naphthoquinones, with excitation over the range 530-590 nm. Luminescence spectrophotometry of developed lysine, glycine and serine spots on paper was used to confirm that the naphthoquinones were reacting with amino acids in the latent fingermark. 相似文献
4.
M. A. Berghot 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):627-637
The chlorine atom of chloroenamineone in the quinonoid compounds 1a-f and 7 was activated by the reaction with benzenesulphonyl chloride to form naphthoquinonid moiety fused with linear or angular heterocyclic systems as carbazoles 2a-c , phenazines 3a , b and 5a-c , phenoxazines 3c phenothiazine 3d , quinoxalinophenazine 6a , quinoxalinophenoxazine 6b , quinoxalinophenthiazine 6c , oxadiazine 8 , thiadiazine 9 , and pyrazole 10 . The mechanism of the latter derivative was discussed. Spectroscopic data of all new products are given. Additionally, the antimicrobial activity of some reported compounds was screened. 相似文献
5.
Xi‐Bin Xiao Yue‐Xing Lin Geng‐Bo Xu Xu‐Bo Gong Ying Gu Jie‐Feng Tong Jing Yang 《Helvetica chimica acta》2011,94(3):404-409
A new naphthoquinone, 6‐hydroxy‐α‐dunnione ( 1 ) and a new binaphthoquinone, methyl 1,1′,4,4′‐tetrahydro‐3‐hydroxy‐1,1′,4,4′‐tetraoxo[2,2′‐binaphthalene]‐3′‐carboxylate ( 2 ), along with ten known compounds, including naphthoquinones, anthraquinones, and phenylethanoid glucosides, were isolated from the roots of Didymocarpus hedyotideus Chun . Their structures were identified by spectroscopic analyses, particularly 1D‐ and 2D‐NMR spectroscopy. The cytotoxic activities of the two new naphthoquinones were also evaluated. 相似文献
6.
Yu‐Jiao Zhong Qing‐Fa Wen Cong‐Ying Li Xue‐Hui Su Zhi‐Peng Yuan Yan‐Fang Li 《Helvetica chimica acta》2013,96(9):1750-1756
Two new naphthoquinones, (2R)‐6,8‐dihydroxy‐α‐dunnione ( 1 ), 6,8‐dihydroxy‐2,7‐dimethoxy‐3‐(1,1‐dimethylprop‐2‐enyl)‐1,4‐naphthoquinone ( 2 ), together with three known compounds, (2R)‐6,8‐dihydroxy‐7‐methoxy‐α‐dunnione ( 3 ), nevadensin ( 4 ), and lysioside C ( 5 ), were isolated from the whole plant of Lysionotus pauciflorus. Their structures were established by spectroscopic methods. Hydroxylated naphthoquinones are reported to occur in a Lysionotus species for the first time. The cytotoxic activities of compounds 1 – 3 were evaluated in vitro against a panel of tumor cell lines. 相似文献
7.
《合成通讯》2013,43(18):3389-3397
Abstract The efficient synthesis of 2‐hydroxy‐3‐iodo‐1,4‐naphthoquinone (3), 2‐amino‐3‐iodo‐1,4‐naphthoquinone (4), and 2‐iodo‐1,4‐naphthoquinone (5) have been developed using the parent naphthoquinone in combination with the charge‐transfer complex between iodine and morpholine. 相似文献
8.
David Bailey 《Tetrahedron letters》2004,45(12):2511-2513
An efficient synthesis of 6,7-disubstituted naphthoquinones and 2,3,6,7-tetrasubstituted anthraquinones were developed using the reaction of thiophene dioxides and benzoquinone and naphthoquinone derivatives, respectively. 相似文献
9.
Mónica Treus Cristian O. Salas Juan C. Estévez Ricardo A. Tapia Ramón J. Estévez 《Tetrahedron》2010,66(52):9986-9995
Treatment of N-carbethoxy-1-benzylideneisoquinolines with LDA gives N-ethoxycarbonyl-1-amino-1-(2-vinylphenyl)-2-phenylethylenes, which can easily be transformed into N-carbethoxy-1-amino-2-phenylnaphthalenes. Bischler-Napieralski reaction of these latter compounds affords the corresponding benzo[c]phenanthridines, while their hydrolysis and subsequent oxidation constitutes a novel route to 2-phenyl-1,4-naphthoquinones. 相似文献
10.
Two enantiomic natural products with wound-healing properties , alkannin ( 1 ) and shikonin ( 2 ), are accessible by a short and efficient total synthesis. The success was achieved by a novel protecting system for masking of 5,8-dihydroxy-1,4-naphthoquinones (naphthazarins) and a highly stereoselective ketone reduction. 相似文献