- Synthesis and stereoisomerization of 2-(1-alkoxyimino-2,2,2-trifluoroethyl) -5-trimethylsilylfurans
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2-(1-Alkoxyimino-2,2,2-trifluoroethyl)-5-trimethylsilylfurans were synthesized by the condensation of 2-(trifluoroacetyl)-5-trimethylsilylfuran with alkoxyamines. According to 1H and 19F NMR spectroscopic data, the alkoxyimino group in the E-isomers descreens the H-3 and H-4 protons of the furan ring more strongly than in the Z-isomers, shifting their signals downfield. The fluorine atoms of the α-trifluoromethyl group in the Z-isomer are characterized by a downfield shift in relation to the E-isomer. 2005 Springer Science+Business Media, Inc.
- Melnik,Vorona,Veinberg,Popelis,Ignatovich,Lukevics
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Read Online
- Electrochemical access to benzimidazolone and quinazolinone derivatives: Via in situ generation of isocyanates
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Isocyanates are the key intermediates for several organic transformations towards the synthesis of diverse pharmaceutical targets. Herein, we report the development of an oxidant-free protocol for electrochemical in situ generation of isocyanates. This strategy highlights expedient access to benzimidazolones and quinazolinones and eliminates the need for exogenous oxidants. Furthermore, detailed mechanistic studies provide strong support towards our hypothesis of in situ isocyanate generation. This journal is
- Saha, Debarshi,Taily, Irshad Maajid,Naik, Sumitra,Banerjee, Prabal
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supporting information
p. 631 - 634
(2021/01/29)
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- Synthesis and antibacterial evaluation of (E)-1-(1H-indol-3-yl) ethanone O-benzyl oxime derivatives against MRSA and VRSA strains
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Infections caused due to multidrug resistant organisms have emerged as a constant menace to human health. Even though numerous antibiotics are currently available for treating infectious diseases, a great number of bacterial strains have acquired resistance to many of them. Among these, infections caused due to Staphylococcus aureus are predominant in adult and paediatric population. Indole is a prominent chemical scaffold found in many pharmacologically active natural products and synthetic drugs. A number of oxime ether containing compounds have attracted attention of researchers owing to their interesting biological properties. Current work details the synthesis of indole containing oxime ether derivatives and their evaluation for antimicrobial activity against a panel of bacterial and mycobacterial strains. Synthesized compounds demonstrated good to moderate activity against drug-resistant S. aureus including resistant to vancomycin. Among all, compound 5h was found to possess potent activity against susceptible as well as MRSA and VRSA strains of S. aureus with MIC of 1 μg/mL and 2–4 μg/mL respectively. In addition, compound 5h was found to be non-toxic to Vero cells and exhibited good selectivity index of >40. Further, 5h, E-9a and E-9b possessed good biofilm inhibition against S. aureus. With these assuring biological properties, synthesized compounds could be potential prospective antimicrobial agents.
- Akunuri, Ravikumar,Veerareddy, Vaishnavi,Kaul, Grace,Akhir, Abdul,Unnissa, Tanveer,Parupalli, Ramulu,Madhavi,Chopra, Sidharth,Nanduri, Srinivas
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supporting information
(2021/08/27)
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- Preparation method of benzyloxyamine hydrochloride
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The invention discloses a preparation method of benzyloxyamine hydrochloride. The preparation method comprises the following steps: (1) dispersing ketoxime 2 and alkali metal hydroxide into a mixed solvent of dimethylacetamide and water at the temperature of 50-55 DEG C and the stirring speed of 100-120 rpm; (2) dropwise adding a benzyl halide compound 1 into a dispersion body obtained in the step (1), reacting for 130-140 minutes at the temperature of 60-65 DEG C after dropwise adding is completed, then cooling to room temperature, adding water, extracting by using normal hexane, and distilling an organic phase under reduced pressure to obtain a product 3; and (3) adding the product 3 obtained in the step (2) into a mixed solution of methanol and a hydrochloric acid solution with the mass concentration of 38% , reacting for 200-220 minutes at the temperature of 35-40 DEG C and at the stirring speed of 80-100 rpm, distilling under reduced pressure until a solid is separated out, cooling to room temperature, washing the solid with petroleum ether, and drying to obtain the target product 4-benzyloxyamine hydrochloride. According to the preparation method, the total yield can reach 95% or above, and the product purity can reach 99% or above.
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Paragraph 0059-0061; 0064
(2021/04/14)
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- Structure-activity relationships of pyrimidine nucleotides containing a 5′-α,β-methylene diphosphonate at the P2Y6 receptor
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The Gq-coupled P2Y6 receptor (P2Y6R) is a component of the purinergic signaling system and functions in inflammatory, cardiovascular and metabolic processes. UDP, the native P2Y6R agonist and P2Y14R partial agonist, is subject to hydrolysis by ectonucleotidases. Therefore, we have synthesized UDP/CDP analogues containing a stabilizing α,β-methylene bridge as P2Y6R agonists and identified compatible affinity-enhancing pyrimidine modifications. A distal binding region on the receptor was explored with 4-benzyloxyimino cytidine 5′-diphosphate analogues and their potency determined in a calcium mobilization assay. A 4-trifluoromethyl-benzyloxyimino substituent in 25 provided the highest human P2Y6R potency (MRS4554, 0.57 μM), and a 5-fluoro substitution of the cytosine ring in 28 similarly enhanced potency, with >175- and 39-fold selectivity over human P2Y14R, respectively. However, 3-alkyl (31–33, 37, 38), β-D-arabinofuranose (39) and 6-aza (40) substitution prevented P2Y6R activation. Thus, we have identified new α,β-methylene bridged N4-extended CDP analogues as P2Y6R agonists that are highly selective over the P2Y14R.
- Dobelmann, Clemens,Gopinatth, Varun,Jacobson, Kenneth A.,Jain, Shanu,Junker, Anna,Oliva, Paola,Phung, Ngan B.,Scortichini, Mirko,Toti, Kiran S.
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supporting information
(2021/06/15)
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- Vinylogous Aza-Michael Addition of Urea Derivatives with p-Quinone Methides Followed by Oxidative Dearomative Cyclization: Approach to Spiroimidazolidinone Derivatives
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Herein, we report an efficient protocol for the synthesis of spiro-imidazolidinone-cyclohexadienones from p-quinone methides (p-QMs) and dialkyloxy ureas under mild conditions. The strategy follows a two-step process involving an initial vinylogous conjugate addition of urea derivatives to p-QMs, followed by oxidative dearomative cyclization of open-chain product to the projected spiro-imidazolidinones. This protocol exhibits good functional group tolerance and provides a straightforward method to access spiro-imidazolidinone-cyclohexadienones. In follow-up chemistry, we have shown the debenzylation of spiroimidazolidinones to give N-hydroxycyclic ureas. (Figure presented.).
- Kaur, Navpreet,Singh, Priyanka,Banerjee, Prabal
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supporting information
p. 2813 - 2824
(2021/04/21)
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- Palladium-catalyzed regio- And stereoselective access to allyl ureas/carbamates: Facile synthesis of imidazolidinones and oxazepinones
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Typically, transition metal catalysis enforces the stereodefined outcome of a reaction. Here we disclose the palladium-catalyzed regio- and stereoselective access to allylic ureas/carbamates and their further exploitation to diverse cyclic structures under operationally simple reaction conditions. This protocol features palladium-catalyzed decarboxylative amidation of highly modular VECs with good to excellent yield, minimal waste production, wide substrate scope, and low catalyst loading. In follow-up chemistry, we demonstrated the debenzylation of vinylic imidazolidinones to N-hydroxycyclic ureas and regioselective derivatization towards the facile synthesis of halohydrins and oxiranes under mild reaction conditions in good to excellent yields. This journal is
- Banerjee, Prabal,Saha, Debarshi,Taily, Irshad Maajid
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supporting information
p. 6564 - 6570
(2020/11/10)
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- Design, synthesis and evaluation of wound healing activity for β-sitosterols derivatives as potent Na+/K+-ATPase inhibitors
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β-Sitosterols, is a common steroid that can be identified in a variety of plants and their efficacy in promoting wound healing has been demonstrated. Na+/K+-ATPase, more than a pump, its signal transduction function for involvement in cell growth regulation attracts widespread concern. The Na+/K+-ATPase/Src receptor complex can serve as a receptor involved in multiple signaling pathways including promoting wound healing pathways. To finding potent accelerating wound healing small molecular, we choose the high inhibitory activity of Na+/K+-ATPase and non-cardiotoxic natural compound, β-sitosterol as the substrate. A series of β-sitosterol derivatives were designed, synthesized and evaluated as potential Na+/K+-ATPase inhibitors. Among them, compounds 31, 47, 49, showed improved inhibitory activity on Na+/K+-ATPase, with IC50 value of 3.0 μM, 3.4 μM, 2.2 μM, which are more potent than β-sitosterol with IC50 7.6 μM. Especially, compound 49 can induce cell proliferation, migration and soluble collagen production in L929 fibroblasts. Compared to model, compound 49 can accelerate wound healing in SD rats. Further studies indicated that 49 can activate the sarcoma (Src), uptake the protein kinase B (Akt), extracellular signal-regulated kinase (ERK) proteins expression in a concentration dependent manner. Finally, binding mode of compound 49 with Na+/K+-ATPase was studied, which provides insights into the determinants of potency and selectivity. These results proved β-stitosterol derivative 49 can serve as an effective inhibitor of Na+/K+-ATPase and potential candidate for accelerating wound healing agents.
- Cui, Shaoyu,Jiang, Hongli,Chen, Lei,Xu, Jian,Sun, Wenzhuo,Sun, Haopeng,Xie, Zijian,Xu, Yunhui,Yang, Fubai,Liu, Wenyuan,Feng, Feng,Qu, Wei
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- [3+3] Annulation via Ring Opening/Cyclization of Donor–Acceptor Cyclopropanes with (Un)symmetrical Ureas: A Quick Access to Highly Functionalized Tetrahydropyrimidinones
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A mild and straight-forward access to pharmacologically privileged tetrahydropyrimidinones exploiting readily available Donor–Acceptor cyclopropanes (DACs) is reported. This methodology involves the Lewis acid catalyzed synthesis of uriedo-malonates from (un)symmetrical ureas and DACs followed by I2-base mediated cyclization to their corresponding tetrahydropyrimidinones. The cyclization protocol involves nucleophilic attack of the nitrogen of urea on the newly generated electrophilic acceptor end of DAC. The post functionalization offered potential biologically active molecules.
- Taily, Irshad Maajid,Saha, Debarshi,Banerjee, Prabal
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p. 7804 - 7813
(2019/12/27)
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- Preparation method of O-benzylhydroxylamine hydrochloride
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The invention discloses a preparation method of O-benzylhydroxylamine hydrochloride, and relates to the technical field of organic synthesis. The method comprises the following steps: synchronously dropwise adding alcoholic solutions of benzyl halide and alkoxide into oxime to perform a reaction; when no benzyl halide exists in the reaction system, carrying out solid-liquid separation, dropwise adding dilute hydrochloric acid for carrying out hydrolytic rectification, and distilling while dropwise adding the dilute hydrochloric acid to separate out ketone; concentrating the reaction solution and separating out O-benzylhydroxylamine hydrochloride; and drying the benzylamine hydrochloride to obtain an O-benzylhydroxylamine hydrochloride pure product. Oxime is used as a raw material, and thefinally generated ketone or aldehyde can also be recycled to synthesize corresponding oxime. According to the method, the atom utilization rate is improved, the production cost of the product is reduced, the emission of three wastes is reduced, and the goal of green production is achieved.
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Paragraph 0037-0056
(2019/07/16)
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- Sterol derivatives and its preparation method and application
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The invention discloses a sterol derivative of beta-sitosterol, beta-stigmasterol and cholesterol, and is shown as a formula VI. The invention also discloses a preparation method of the sterol derivative. The invention also discloses application of the sterol derivative to the aspect of preparation of wound healing promoting medicine. By starting from easily obtained natural products, the beta-sitosterol, the beta-stigmasterol and the cholesterol are used as starting raw materials; the synthetic method is simple; better operability and reaction yield are realized. The prepared sterol derivative has the obvious wound healing promoting activity; the multiplication, migration and collagen synthesis capability on L929 mechanocytes is obviously higher than that of the raw material and positive control medicine recombinant human bFGF (basic fibroblast growth factor). Compared with protide type medicine (such as bFGF), the prepared sterol derivative has more diversified dosage forms and medication modes; the reference is provided for the application in the field of wound healing promoting. The formula VI is shown as the accompanying diagram.
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Paragraph 0139-0141
(2019/05/19)
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- O-benzyl-N-(9-acridinyl)hydroxylamines
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A series of O-benzyl-N-(9-acridinyl)hydroxylamines was prepared, isolated, and evaluated for biological activity using both thermal denaturation and MTT assays. Changes in the thermal denaturation temperature of genomic calf-thymus DNA ranged from +6.6 °C to +20.2 °C. MTT assays on SNB-19 glioblastoma cells provided biological activity that ranged from 17.4 μM to 33.2 μM. Both evaluation methods of biological activity indicate that substitution of the benzyl group by either electron-withdrawing or electron-donating groups provides a measureable benefit in these assays. The two assays agreed on the magnitude of the interaction for each substitution pattern.
- Johnson, Alyssa L.,Duncan, Nathan,Mosher, Michael D.
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p. 139 - 148
(2018/06/27)
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- Design, synthesis and evaluation of oxime-functionalized nitrofuranylamides as novel antitubercular agents
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A series of oxime-functionalized nitrofuranylamides were designed, synthesized and evaluated for their in vitro anti-mycobacterial activities against MTB H37Rv and drug-resistant clinical isolates. Among them, two compounds 7a and 7b exhibited excellent activity against the three tested strains. Both of them were comparable to the first-line anti-TB agents INH and RIF against MTB H37Rv, and were far more potent than INH and RIF against MDR-TB 16833 and 16995 strains. Thus, both of them could act as leads for further optimization.
- Fan, Yi-Lei,Wu, Jian-Bing,Ke, Xing,Huang, Zhong-Ping
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supporting information
p. 3064 - 3066
(2018/08/21)
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- O - substituted hydroxylamine hydrochloride and its preparation method (by machine translation)
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The present invention provides a O - substituted hydroxylamine hydrochloride and its preparation, wherein the preparation method comprises the following steps: step S1, to the acetyl hydroximic acid ethyl ester in ethanol solution of adding sodium hydroxide, in addition at the same time instillment halohydrocarbon, chloride or acyl chloride substitution reaction to take place, then added to the water in order to separate out the O - substituted [...]; step S2, the said O - substituted [...] adding hydrochloric acid solution in order to produce reflux reaction O - substituted hydroxylamine hydrochloride. According to the embodiment of the invention of the O - substituted hydroxylamine hydrochloride of the preparation method, high purity of the product can be obtained, and the method is safe, easy to process, the process is simple, and is suitable for industrial production. (by machine translation)
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Paragraph 0079; 0082; 0083
(2018/10/11)
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- First discovery of novel 3-hydroxy-quinazoline-2,4(1H,3H)-diones as specific anti-vaccinia and adenovirus agents via ‘privileged scaffold’ refining approach
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A series of 1,2,3-triazolyl 3-hydroxy-quinazoline-2,4(1H,3H)-diones was constructed utilizing Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) method. The biological significance of the novel synthesized quinazolines was highlighted by evaluating them in vitro for antiviral activity, wherein several compounds exhibited excellent activity specifically against vaccinia and adenovirus. Especially, 24b11 displayed the most potent inhibitory activity against vaccinia with an EC50value of 1.7 μM, which was 15 fold than that of the reference drug Cidofovir (EC50= 25 μM). 24b13 was the most potent compound against adenovirus-2 with an EC50value of 6.2 μM, which proved lower than all the reference drugs. Preliminary structure–activity relationships were also discussed. To the best of our knowledge, no data are present in the literature on antiviral activity of 3-hydroxy-quinazoline-2,4(1H,3H)-diones against DNA-viruses. Thus, these findings warrant further investigations (library expansion and compound refinement) on this novel class of antiviral agents.
- Kang, Dongwei,Zhang, Heng,Zhou, Zhongxia,Huang, Boshi,Naesens, Lieve,Zhan, Peng,Liu, Xinyong
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supporting information
p. 5182 - 5186
(2016/11/09)
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- Direct cycle between co-product and reactant: An approach to improve the atom economy and its application in the synthesis and protection of primary amines
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Two important goals of green chemistry are to maximize the efficiency of reactants and to minimize the production of waste. In this study, a novel approach to improve the atom economy of a chemical process was developed by incorporating a direct cycle between a co-product and a reactant of the same reaction. To demonstrate this concept, recoverable 3,4-diphenylmaleic anhydride (1) was designed and used for the atom-economical synthesis of aliphatic primary amines from aqueous ammonia. In each individual cycle, only ammonia and alkyl halide were consumed, and 1 was recovered in nearly a quantitative yield. In this approach for developing atom-economical protecting agents, 1 showed good performance as a recoverable protecting agent for primary amines. The broad substrate scope, good tolerance to various reaction conditions, and high reaction and recovery rates make 1 a valuable complement to conventional primary amine protecting agents.
- Guan, Qi,Jiang, Mingyang,Wu, Junhui,Zhai, Yanpeng,Wu, Yue,Bao, Kai,Zhang, Weige
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supporting information
p. 5794 - 5799
(2016/11/06)
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- NOVEL VASCULAR LEAKAGEAGE INHIBITOR
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The present disclosure relates to a novel vascular leakage inhibitor. The novel vascular leakage inhibitor of the present invention inhibits the apoptosis of vascular endothelial cells, inhibits the formation of actin stress fibers induced by VEGF, and enhances the cortical actin ring structure, thereby inhibiting vascular leakage. Accordingly, the vascular leakage inhibitor of the present invention can prevent or treat various diseases caused by vascular leakage. Since the vascular leakage inhibitor of the present invention is synthesized from commercially available or easily synthesizable pregnenolones, it has remarkably superior feasibility of commercial synthesis.
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Paragraph 0092
(2015/01/07)
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- Metal-Free: A novel and efficient aerobic oxidation of primary amines to oximes using N, N', N''-trihydroxyisocyanuric acid and acetaldoxime as catalysts in water
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A general, efficient, and metal-free method for aerobic oxidation of aromatic primary amines to the corresponding oximes catalyzed by N,N',N''-trihydroxyisocyanuric acid and acetaldoxime with water as solvent is described. This practical method can use air as economic and green oxidant, water as green solvent, and tolerates a wide range of substrates, which can afford the target oximes in moderate to good yields. Georg Thieme Verlag Stuttgart. New York.
- Yu, Jiatao,Lu, Ming
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p. 1873 - 1878
(2014/08/18)
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- Rapid synthesis of alkoxyamine hydrochloride derivatives from alkyl bromide and N,N′-Di-tert-butoxycarbonylhydroxylamine [(Boc)2NOH]
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The conventional route to alkoxyamine hydrochloride derivatives is by reaction of alkyl bromides with N-hydroxyphthalimide or N-hydroxysuccinimide followed by addition of hydrazine and HCl. Transformation of an alkyl bromide to the corresponding alkoxyamine hydrochloride can be accomplished more rapidly in good yields without using hazardous hydrazine by reaction of (Boc) 2NOH (N,N′-di-tert-butoxycarbonylhydroxylamine) and alkyl bromide followed by addition of HCl. Alkoxyamine hydrochlorides are powerful reagents in organic synthesis that can be used to synthesize alkoxyimino derivatives after condensation with a ketone or aldehyde. Copyright
- Jayasekara, P. Suresh,Jacobson, Kenneth A.
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supporting information
p. 2344 - 2347
(2014/07/22)
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- Synthesis, biological evaluation, and molecular docking studies of 2,6-dinitro-4-(trifluoromethyl)phenoxysalicylaldoxime derivatives as novel antitubulin agents
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A series of 2,6-dinitro-4-(trifluoromethyl)phenoxysalicylaldoxime derivatives (1h-20h) have been designed and synthesized, and their biological activities were also evaluated as potential antiproliferation and tubulin polymerization inhibitors. Among all the compounds, 2h showed the most potent activity in vitro, which inhibited the growth of MCF-7, Hep-G2 and A549 cell lines with IC50 values of 0.70 ± 0.05, 0.68 ± 0.02 and 0.86 ± 0.05 μM, respectively. Compound 2h also exhibited significant tubulin polymerization inhibitory activity (IC50 = 3.06 ± 0.05 μM). The result of flow cytometry (FCM) demonstrated that compound 2h induced cell apoptosis. Docking simulation was performed to insert compound 2h into the crystal structure of tubulin at colchicine binding site to determine the probable binding model. Based on the preliminary results, compound 2h with potent inhibitory activity in tumor growth may be a potential anticancer agent.
- Zhao, Ting-Ting,Lu, Xiang,Yang, Xian-Hui,Wang, Li-Ming,Li, Xi,Wang, Zhong-Chang,Gong, Hai-Bin,Zhu, Hai-Liang
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experimental part
p. 3233 - 3241
(2012/07/14)
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- Synthesis and Antimicrobial Activities of Oximes Derived from O- Benzylhydroxylamine as FabH Inhibitors
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Forty-three oxime derivatives were synthesized by allowing O-benzylhydroxylamines to react with primary benzaldehydes or salicylaldehydes; these products were gauged as potential inhibitors of β-ketoacyl-(acyl-carrier-protein) synthaseIII (FabH). Among the 43 compounds, 38 are reported herein for the first time. These compounds were assayed for antimicrobial activities against Escherichia coli, Pseudomonas aeruginosa, Pseudomonas fluorescens, Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis. Compounds with prominent antibacterial activities were tested for their E. coli FabH inhibitory activities. 3-((2,4 Dichlorobenzyloxyimino) methyl) benzaldehyde O-2,4-dichlorobenzyl oxime (44) showed the best antibacterial activity, with minimum inhibitory concentrations of 3.13-6.25μgmL-1 against the tested bacterial strains, exhibiting the best E. coli FabH inhibitory activity, with an IC50 value of 1.7mM. Docking simulations were performed to position compound 44 into the E. coli FabH active site in order to determine the most probable binding conformation.
- Luo, Yin,Zhang, Li-Rong,Hu, Yang,Zhang, Shuai,Wang, Xiao-Ming,Zhu, Hai-Liang,Fu, Jie
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p. 1587 - 1593,7
(2020/08/31)
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- Metal-free artificial nucleases based on simple oxime and hydroxylamine scaffolds
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Hydrolysis of DNA is of increasing importance in biotechnology and medicine. In this Letter, we present the DNA-cleavage potential of metal-free hydroxylamines and oximes as new members of nucleic acid cleavage agents.
- Fernandes, Luciano,Fischer, Franciele L.,Ribeiro, Carolina W.,Silveira, Gustavo P.,Sa, Marcus M.,Nome, Faruk,Terenzi, Hernan
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supporting information; experimental part
p. 4499 - 4502
(2009/04/08)
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- Synthesis and fungicidal activity of macrolactams and macrolactones with an oxime ether side chain
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Three series of novel macrolactams and macrolactones - 12-alkoxyimino- tetradecanlactam, 12-alkoxyiminopentadecanlactam, and 12-alkoxyiminodecanlactone derivatives (7A, 7B, and 7C) - were synthesized from corresponding 12-oxomacrolactams and 12-oxomacrolactone. Their structures were confirmed by 1H NMR and elemental analysis. The Z and E isomers of 7A and 7B were separated, and their configurations were determined by 1H NMR. These compounds showed fair to excellent fungicidal activities against Rhizoctonia solani Kuehn. It is interesting that the Z and E isomers of most of the compounds have quite different fungicidal activities. The fact that the compounds have a gradual increase of fungicidal activity in the order of 7A, 7C, and 7B indicated that the macrocyclic derivatives with a hydrogen-bonding acceptor (=N-O-) and a hydrogen-bonding donor (-CONH-) on the ring, and a three methylenes distance (CH2CH2CH2) between these two functional groups, exhibited the best fungicidal activity. The bioassay also showed that 7B not only has good fungicidal activity but also may have a broad spectrum of fungicidal activities.
- Huang, Jia-Xing,Jia, Yue-Mei,Liang, Xiao-Mei,Zhu, Wei-Juan,Zhang, Jian-Jun,Dong, Yan-Hong,Yuan, Hui-Zu,Qi, Shu-Hua,Wu, Jin-Ping,Chen, Fu-Heng,Wang, Dao-Quan
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experimental part
p. 10857 - 10863
(2009/11/30)
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- Intermolecular electrophilic O-amination of alcohols
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We report the first examples of an intermolecular electrophilic O-amination of aliphatic alcohols. Thus, the new reagents, fluorenone oxime tosylate, 5a, or mesylate, 5b, permit O-amination of diverse alcohols in the presence of NaH under mild conditions. By following the formation of the resulting oxime ethers, 6, the reaction was shown to be sensitive to steric effects in the alcohol. Furthermore, the presence of an aromatic ring or of a double bond in the alcohol molecule (benzyl, allyl) was found to increase the reaction rate.
- Hassner, Alfred,Patchornik, Guy,Pradhan, Tarun K.,Kumareswaran
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p. 658 - 661
(2007/10/03)
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- Heterocyclic substituted 2-methyl-benzimidazole antiviral agents
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The present invention concerns antiviral compounds, their methods of preparation and their compositions, and use in the treatment of viral infections. More particularly, the invention provides heterocyclic substituted 2-methylbenzimidazole derivatives for the treatment of respiratory syncytial virus infection.
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- L-N6 -(1-iminoethyl)lysine derivatives useful as nitric oxide synthase inhibitors
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There is disclosed a novel amino glycol derivatives of L-N6 -(1-iminoethyl)lysine, pharmaceutical compositions containing these novel compounds, and to their use in therapy, in particular their use as nitric oxide synthase inhibitors.
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- Probing the 'active site' of diamine oxidase: Structure-activity relations for histamine potentiation by O-alkylhydroxylamines on colonic epithelium
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The responses of the canine colonic epithelium to histamine are potentiated by O-alkylhydroxylamines. A study of a series of such compounds suggested that active compounds had the structure R-O-NH2, substitution of a nitrogen led to total loss of activity. The locus of the potentiation effect was traced to the inhibition of diamine oxidase. A new series of aliphatic and aromatic O-alkylhydroxylamines were synthesized to explore further the structure-activity relations of this effect. The potentiating effects of these compounds were determined by examining the changes in short circuit current (I(sc)) produced by histamine and from the activity of a soluble preparation of diamine oxidase. We found that 1) branched compounds are less active than their straight chain counterparts, 2) greater steric bulk of the aliphatic substituent decreased activity, 3) the presence of a double bond had no significant effect though a triple bond reduced activity, 4) longer straight chain compounds were less active than the shorter chain derivatives and 5) all benzylic compounds were less active than the straight chain aliphatics. O-1-benzyl was inactive however the meta or para oxygen substituted compounds as well as the O-(1-E-Cinnamyl) derivative were active. A current model for the action of diamine oxidase proposes a crucial role for a trihydroxyphenylalanine quinone cofactor as part of the active site together with a copper atom. Using molecular modeling based on our inhibition data we are able to define the region of space that is just beyond the reactive carbonyl of the trihydroxyphenylalanine residue at the active site of diamine oxidase. We suggest that a negatively charged species, such as an aspartate or a glutamate, resides in a trough about 7 to 8 A from the trihydroxyphenylalanine carbonyl carbon and this species aids in the strong selective binding of substrates such as putrescine and histamine.
- High,Prior,Bell,Rangachari
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p. 490 - 501
(2007/10/03)
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- New calcium antagonists: Synthesis, X-ray analysis, and smooth muscle relaxing effect of 3-[O-(benzyl-substituted)-oximino-ethers]-hexahydroazepin-2,3-diones
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A series of new Z and E 3-[O-(benzyl-substituted)-oximino-ether]-hexahydroazepin-2,3-diones was prepared from the corresponding hexahydroazepin-2,3-diones and examined as smooth muscle relaxants. E and Z structures were assigned by NMR analysis and confirmed for 16 (E and Z) by an X-ray diffraction using synchrotron radiations. The nitrobenzyl derivative 16 was the most potent in vitro as relaxant of rat trachea precontracted with acetylcholine. The E isomer 16b was more potent than the Z isomer 16a. E isomer 16b is more potent than aminophylline to relax both rat trachea and human bronchus.This derivative acts mainly by inhibiting cellular infux of extracellular calcium since it inhibits potently and dose-dependently the contractions of rat trachea to high concentrations of KCl and to CaCl2 in a depolarizing medium. It appears to act weakly by inducing cGMP and cAMP synthesis. Moreover, its relaxing activity is not related to an inhibition of phosphodiesterases, to opening of potassium channels or to induction of prostaglandin synthesis. Therefore, 16b appears to work mainly as a potent calcium antagonist. (C) 1999 Elsevier Science Ltd.
- El From, Hayat,Pera, Marie-Helene,Leclerc, Gerard,Tranqui, Duc,Corompt, Emmanuelle,Bessard, Germain,Devillier, Philippe
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p. 1655 - 1663
(2007/10/03)
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- Synthesis of 5-Substituted 1-Hydroxy-1,2,3-triazoles through Directed Lithiation of 1-(Benzyloxy)-1,2,3-triazole
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1-(Benzyloxy)-1,2,3-triazole, prepared by selective benzylation of 1-hydroxy-1,2,3-triazole or by oxidative cyclization of 2-hydrazonoglyoxal O-benzyloxime, was metalated exclusively at the 5-position upon treatment with n-butyllithium. The anion formed reacted with a series of electrophiles. In this way carbon, halogen, sulfur, silicon, and tin substituants could be introduced at the 5-position. Subsequent removal of the benzyl group by palladium-catalyzed hydrogenolysis or by treatment with hydrochloric acid afforded the corresponding 5-substituted 1-hydroxy-1,2,3- triazoles.
- Uhlmann, Peter,Felding, Jakob,Vedso, Per,Begtrup, Mikael
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p. 9177 - 9181
(2007/10/03)
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- A convenient large scale synthesis of O-benzylhydroxylamine
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Synthetically useful O-benzylhydroxylamine can be conveniently prepared in large scale by reaction of N-hydroxyphthalimide and benzyl chloride in phase transfer conditions, followed by acidic hydrolysis of N-benzyloxyphthalimide. The overall yield is over 65%.
- Bonaccorsi, Fabrizio,Giorgi, Raffaello
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p. 1143 - 1147
(2007/10/03)
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- Process for the preparation of O-substituted hydroxylammonium salts
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Preparation of O-substituted hydroxylammonium salts I (L=halogen, hydrogensulfate; X=H, alkyl; R1 =unsubst. or subst. phenyl, thienyl, furanyl, pyrrolyl or --CR2 =CR3 R4 ; R2, R3, R4 =H, halogen or alkyl) by reaction of an acetone oxime O-allyl or --O--benzyl ether II STR1 with water and a mineral acid H--L with continuous removal of the acetone formed in this process, by carrying out the hydrolysis batchwise at 0°-50° C. and under a pressure of 10-500 mbar is described. The O-substituted hydroxylammonium salts I are intermediates for plant protection agents and pharmaceuticals.
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- NMDA antagonists
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The present invention is directed to a new class of 4-(oxoalkyl)phosphono, 4(oxime alkyl)phosphono, or 4-(hydrazine alkyl)phosphono, 2-piperazine carboxylic derivatives that are useful as NMDA antagonists
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- Stereoselective reduction of α-hydroxy oxime ethers: A convenient route to cis-1,2-amino alcohols
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Reduction of cyclic α-hydroxyketoximes with borane provides an excellent, high yielding, regio- and stereoselective route to cis-1,2-aminoalcohols.
- Ghosh,Mckee,Sanders
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p. 711 - 714
(2007/10/02)
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- Reactions of N-Acyl-O-arylhydroxylamines: Part IV - Preparation of Some N-Arylsulphonyl-O-arylhydroxylamines
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A number of N-arylsulphonyl-O-alkylhydroxylamines (III) have been prepared by condensing appropriate alkoxyamines with arylsulphonyl chlorides in the presence of a base.The alkoxyamines have been obtained from the corresponding alkoxyamine hydrochlorides or hydrobromides (II) which in turn have been prepared by the hydrolysis of appropriate N-benzoyl-O-alkylhydroxylamines (I) with ethanolic hydrogen chloride or hydrogen bromide.The structure assignments of III are based on elemental analyses, chemical reaction and spectral (IR, PMR) data.
- Singha, A. S.,Misra, B. N.
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p. 361 - 363
(2007/10/02)
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