- Structure-activity relationships of β-hairpin mimics as modulators of amyloid β-peptide aggregation
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Aggregation of amyloid proteins is currently involved in more than 20 serious human diseases that are actually untreated, such as Alzheimer's disease (AD). Despite many efforts made to target the amyloid cascade in AD, finding an aggregation inhibiting co
- Tonali, Nicolo,Kaffy, Julia,Soulier, Jean-Louis,Gelmi, Maria Luisa,Erba, Emanuela,Taverna, Myriam,van Heijenoort, Carine,Ha-Duong, Tap,Ongeri, Sandrine
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Read Online
- Alkaline aqueous solution promoted debromination of 1,2 dibromo-fluorocarbons – A convenient method for electron deficient perfluorovinyl ethers
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A facile and efficient base-mediated protocol for debromination of vic-dibromides in perfluoroalkyl(aryl) compounds in aqueous medium has been demonstrated. With mild reaction conditions, the developed strategy has a good substrate scope and electron-deficient olefin products were obtained in good yields. A mechanistic explanation of the debromination is offered with three key experimental observations: (1) the reactions are accelerated by the more electron-rich nucleophiles, (2) the reactions are promoted by the more electron poor vic-dibromides in perfluoroalkyl compounds, and (3) the nucleophilic side reaction is preventable. It is evident that the electronic factors strongly dictate vic-dibromides elimination to the perfluorovinyl ethers, which are the precursors for various perfluorinated polymers. The different reaction conditions were tested in implicit solvent (water) conditions, which helped to confirm the E2-like mechanism.
- Mei, Hua,McCloud, Rebecca,Ibrahim, Faisal,Nworie, Chimaroke,Musket, Anna
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Read Online
- Chromoselective Synthesis of Sulfonyl Chlorides and Sulfonamides with Potassium Poly(heptazine imide) Photocatalyst
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Among external stimuli used to promote a chemical reaction, photocatalysis possesses a unique one—light. Photons are traceless reagents that provide an exclusive opportunity to alter chemoselectivity of the photocatalytic reaction varying the color of incident light. This strategy may be implemented by using a sensitizer capable to activate a specific reaction pathway depending on the excitation light. Herein, we use potassium poly(heptazine imide) (K-PHI), a type of carbon nitride, to generate selectively three different products from S-arylthioacetates simply varying the excitation light and otherwise identical conditions. Namely, arylchlorides are produced under UV/purple, sulfonyl chlorides with blue/white, and diaryldisulfides at green to red light. A combination of the negatively charged polyanion, highly positive potential of the valence band, presence of intraband states, ability to sensitize singlet oxygen, and multi-electron transfer is shown to enable this chromoselective conversion of thioacetates.
- Antonietti, Markus,Guldi, Dirk M.,Markushyna, Yevheniia,Savateev, Aleksandr,Schü?lbauer, Christoph M.,Ullrich, Tobias
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supporting information
p. 20543 - 20550
(2021/08/12)
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- Synthesis of magnetic chitosan supported metformin-Cu(II) complex as a recyclable catalyst for N-arylation of primary sulfonamides
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The application of chitosan, which has received much attention as a natural polymer and effective support, has many advantages such as biodegradability and biocompatibility. In this study, the immobilization of a copper complex on the magnetic chitosan bearing metformin ligand has been developed through immobilizing structurally defined metformin with long tail of (3-chloropropyl)trimethoxysilane (TMOS). The synthesized Fe3O4-chitosan@metformin-Cu(II) complex (Fe3O4-CS@Met-Cu(II)) was used as an effective, reusable and magnetic catalyst in the N-arylation of different derivatives of primary sulfonamides with arylboronic acids in ethanol. The primary sulfonamides were prepared from the reaction of sulfonyl chlorides with sodium cyanate in water under ultrasonic irradiation. Utilizing a wide variety of substrates in EtOH as a green solvent, high yields of the primary and secondary sulfonamides, easy work-up along with the excellent recovery and reusability of the catalyst, make this process a simple, economic and environmentally benign method. The synthesized Fe3O4-CS@Met-Cu(II) was characterized using various techniques such as XRD (X-ray diffraction), EDS (energy-dispersive X-ray spectroscopy), elemental mapping, TEM (transmission electron microscopy), FESEM (field emission scanning electron microscopy), VSM (vibrating sample magnetometer), ICP-MS (inductively coupled plasma mass spectroscopy), TGA (thermogravimetric analysis) and FT-IR (Fourier-transform infrared spectroscopy) analyses. The catalyst can be recycled and reused 5 times with no considerable loss of catalytic activity.
- Ahmadpoor, Fatemeh,Nasrollahzadeh, Mahmoud,Nezafat, Zahra,Pakzad, Khatereh
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- Development of succinimide-based inhibitors for the mitochondrial rhomboid protease PARL
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While the biochemistry of rhomboid proteases has been extensively studied since their discovery two decades ago, efforts to define the physiological roles of these enzymes are ongoing and would benefit from chemical probes that can be used to manipulate the functions of these proteins in their native settings. Here, we describe the use of activity-based protein profiling (ABPP) technology to conduct a targeted screen for small-molecule inhibitors of the mitochondrial rhomboid protease PARL, which plays a critical role in regulating mitophagy and cell death. We synthesized a series of succinimide-containing sulfonyl esters and sulfonamides and discovered that these compounds serve as inhibitors of PARL with the most potent sulfonamides having submicromolar affinity for the enzyme. A counterscreen against the bacterial rhomboid protease GlpG demonstrates that several of these compounds display selectivity for PARL over GlpG by as much as two orders of magnitude. Both the sulfonyl ester and sulfonamide scaffolds exhibit reversible binding and are able to engage PARL in mammalian cells. Collectively, our findings provide encouraging precedent for the development of PARL-selective inhibitors and establish N-[(arylsulfonyl)oxy]succinimides and N-arylsulfonylsuccinimides as new molecular scaffolds for inhibiting members of the rhomboid protease family.
- Andrews, Charlotte L.,Cardozo, Joaquin M.,Chow, Alyssa S.,Crainic, Jennifer A.,Parsons, William H.,Rutland, Nicholas T.,Sheehan, Brendan K.
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supporting information
(2021/08/04)
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- The polyhedral nature of selenium-catalysed reactions: Se(iv) species instead of Se(vi) species make the difference in the on water selenium-mediated oxidation of arylamines
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Selenium-catalysed oxidations are highly sought after in organic synthesis and biology. Herein, we report our studies on the on water selenium mediated oxidation of anilines. In the presence of diphenyl diselenide or benzeneseleninic acid, anilines react with hydrogen peroxide, providing direct and selective access to nitroarenes. On the other hand, the use of selenium dioxide or sodium selenite leads to azoxyarenes. Careful mechanistic analysis and 77Se NMR studies revealed that only Se(iv) species, such as benzeneperoxyseleninic acid, are the active oxidants involved in the catalytic cycle operating in water and leading to nitroarenes. While other selenium-catalysed oxidations occurring in organic solvents have been recently demonstrated to proceed through Se(vi) key intermediates, the on water oxidation of anilines to nitroarenes does not. These findings shed new light on the multifaceted nature of organoselenium-catalysed transformations and open new directions to exploit selenium-based catalysis.
- Capperucci, Antonella,Dalia, Camilla,Tanini, Damiano
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supporting information
p. 5680 - 5686
(2021/08/16)
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- Synthesis of new Copper Catalyst with Pyrazole Based Tridentate Ligand and Study of Its Activity for Azide Alkyne Coupling
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Synthesis of new copper catalyst with pyrazole based tridentate ligand and study of its activity for azide alkyne coupling were investigated by researchers. To a solution of acetyl acetone (2.002 g, 20 mmol), 2- nitrophenylhydrazine in ethanol was added five drops of con. HCl and heated at 50° for 1 hour. After confirming the formation of 3, 5-dimethyl-1-(2-nitrophenyl)- 1H-pyrazole by TLC, ice cooled water was added in to the reaction mixture. The precipitate was filtered, washed with water and then hexane. The product formed as yellow precipitate, that precipitate had been filtered by normal filter paper. The product was recrystallized in ethanol. For synthesis, was suspended in 6 mL of deionized and stirred for 4 h until a clear solution was obtained in 50 ml round bottom flask Cu(OAc) 2. The reaction mixture was diluted with water, filtered, washed sequentially with water, methanol and n-hexane. Then dark greenish blue color crystal were formed and used for the reactions. The solid was crystallized in CH2Cl2 to get crystal whose structure was confirmed by single crystal XRD.
- Rajeswari, Panneer Selvam,Nagarajan, Rajendran,P, Sujith K,Emmanuvel, Lourdusamy
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supporting information
(2020/12/03)
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- Bone-seeking matrix metalloproteinase inhibitors for the treatment of skeletal malignancy
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Matrix metalloproteinases (MMPs) are a family of enzymes involved at different stages of cancer progression and metastasis. We previously identified a novel class of bisphosphonic inhibitors, selective for MMPs crucial for bone remodeling, such as MMP-2. Due to the increasing relevance of specific MMPs at various stages of tumor malignancy, we focused on improving potency towards certain isoforms. Here, we tackled MMP-9 because of its confirmed role in tumor invasion, metastasis, angiogenesis, and immuno-response, making it an ideal target for cancer therapy. Using a computational analysis, we designed and characterized potent MMP-2/MMP-9 inhibitors. This is a promising approach to develop and clinically translate inhibitors that could be used in combination with standard care therapy for the treatment of skeletal malignancies.
- Laghezza, Antonio,Piemontese, Luca,Brunetti, Leonardo,Caradonna, Alessia,Agamennone, Mariangela,Di Pizio, Antonella,Pochetti, Giorgio,Montanari, Roberta,Capelli, Davide,Tauro, Marilena,Loiodice, Fulvio,Tortorella, Paolo
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- Metal-Free β-Amino Alcohol Synthesis: A Two-step Smiles Rearrangement
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A novel method for the synthesis of β-amino alcohols has been demonstrated under mild reaction conditions with a broad scope via a two-step Smiles rearrangement. What is more, theoretical calculations have been performed to confirm the rationality of the mechanism. The method has been proved to be notably effective for N-arylated amino alcohols, which are difficult to synthesize by traditional methods.
- Yang, Di,Xie, Cai-Xia,Wu, Xiao-Tian,Fei, Luo-Ran,Feng, Lei,Ma, Chen
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supporting information
p. 14905 - 14915
(2020/11/13)
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- One-pot aerobic oxidative sulfonamidation of aromatic thiols with ammonia by a dual-functional β-MnO2 nanocatalyst
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High-surface-area β-MnO2 (β-MnO2-HS) nanoparticles could act as effective heterogeneous catalysts for the one-pot oxidative sulfonamidation of various aromatic and heteroaromatic thiols to the corresponding sulfonamides using molecular oxygen (O2) and ammonia (NH3) as respective oxygen and nitrogen sources, without the need for any additives.
- Hayashi, Eri,Yamaguchi, Yui,Kita, Yusuke,Kamata, Keigo,Hara, Michikazu
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supporting information
p. 2095 - 2098
(2020/02/26)
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- Rational Design, synthesis and biological evaluation of novel triazole derivatives as potent and selective PRMT5 inhibitors with antitumor activity
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Protein arginine methyltransferase 5 (PRMT5) is responsible for the mono-methylation and symmetric dimethylation of arginine, and its expression level and methyl transferring activity have been demonstrated to have a close relationship with tumorigenesis, development and poor clinical outcomes of human cancers. Two PRMT5 small molecule inhibitors (GSK3326595 and JNJ-64619178) have been put forward into clinical trials. Here, we describe the design, synthesis and biological evaluation of a series of novel, potent and selective PRMT5 inhibitors with antiproliferative activity against Z-138 mantle cell lymphoma cell line. Among them, compound C_4 exhibited the highest potency with enzymatic and cellular level IC50 values of 0.72 and 2.6 μM, respectively, and displayed more than 270-fold selectivity toward PRMT5 over several other isoenzymes (PRMT1, PRMT4 and PRMT6). Besides, C_4 demonstrated obvious cell apoptotic effect while reduced the cellular symmetric arginine dimethylation levels of SmD3 protein. The potency, small size, and synthetic accessibility of this compound class provide promising hit scaffold for medicinal chemists to further explore this series of PRMT5 inhibitors.
- Zhu, Kongkai,Shao, Jingwei,Tao, Hongrui,Yan, Xue,Luo, Cheng,Zhang, Hua,Duan, Wenhu
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p. 775 - 785
(2019/07/22)
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- N-Trifluoromethylthiolated Sulfonimidamides and Sulfoximines: Anti-microbial, Anti-mycobacterial, and Cytotoxic Activity
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Herein we demonstrate the expanded utility of a recently described N-trifluoromethylthiolation protocol to sulfonimidamide containing substances. The novel N-trifluoromethylthio sulfonimidamide derivatives thus obtained were evaluated for antibacterial activity against Mycobacterium tuberculosis (M. tb.) and Mycobacterium abscessus and Gram + Ve (Streptococcus aureus, Bacillus subtilis), and Gram - Ve (Escherichia coli, Pseudomonas aeruginosa) bacteria. Two compounds, 13 and 15 showed high antimycobacterial activity with MIC value of 4-8 μg/mL; i.e. comparable to WHO recommended first line antibiotic for TB infection ethambutol. The same compounds were also found to be cytotoxic in HepG2 cells (compound 13 IC50 = 15 μg/mL; compound 15 IC50 = 65 μg/mL). A structure activity relationship, using matched pair analysis, gave the unexpected conclusion that the trifluoromethylthio moiety was responsible for the cellular and bacterial toxicity. Given the increasing use of the trifluoromethylthio group in contemporary medicinal chemistry, this observation calls for considerations before implementation of the functionality in drug design.
- Thota, Niranjan,Makam, Parameshwar,Rajbongshi, Kamal K.,Nagiah, Savania,Abdul, Naeem Sheik,Chuturgoon, Anil A,Kaushik, Amit,Lamichhane, Gyanu,Somboro, Anou M.,Kruger, Hendrik G.,Govender, Thavendran,Naicker, Tricia,Arvidsson, Per I
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supporting information
p. 1457 - 1461
(2019/10/11)
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- Photochemical C?H Amination of Ethers and Geminal Difunctionalization Reactions in One Pot
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A mild, atom-economic, and metal-free α-C?H amination of ethers using relatively stable nonafluorobutanesulfonyl (nonaflyl, Nf) azide as the aminating reagent to give N-sulfonyl hemiaminals is reported. This enables unprecedented C(sp3) difunctionalization reactions, leading to diverse functionalized amino group containing compounds starting from simple ethers in one pot.
- Hernández-Guerra, Daniel,Hlava?ková, Anna,Pramthaisong, Chiranan,Vespoli, Ilaria,Pohl, Radek,Slanina, Tomá?,Jahn, Ullrich
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p. 12440 - 12445
(2019/08/07)
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- Difluoroamination reagent as well as preparation method and application thereof
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The invention discloses a difluoroamination reagent. The structural formula of the reagent is shown as a formula I, and the structural formula is as shown in the specification, wherein R is -SO2R1; R1 is a benzene ring connected with 1-5 substituent groups; each substituent group on the benzene ring is respectively and independently nitro, fluorine atom or tertiary butyl. The invention further discloses a preparation method of the difluoroamination reagent and application of the reagent in an addition reaction. The difluoroamination reagent disclosed by the invention is stable in chemical property and has high activity when reacted with olefin compounds and dicarbonyl compounds. The fluorine atom can be introduced to a specific position, and the reaction is mild. The defect that the conventional fluorination reagent is high in dangerousness, high in energy and difficult to store is overcome.
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Paragraph 0042; 0043; 0044
(2017/09/13)
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- Sulfonylureas as Concomitant Insulin Secretagogues and NLRP3 Inflammasome Inhibitors
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Insulin-secretory sulfonylureas are widely used, cost-effective treatments for type 2 diabetes (T2D). However, pancreatic β-cells are continually depleted as T2D progresses, thereby rendering the sulfonylurea drug class ineffective in controlling glycaemia. Dysregulation of the innate immune system via activation of the NLRP3 inflammasome, and the consequent production of interleukin-1β, has been linked to pancreatic β-cell death and multiple inflammatory complications of T2D disease. One proposed strategy for treating T2D is the use of sulfonylurea insulin secretagogues that are also NLRP3 inhibitors. We report the synthesis and biological evaluation of nine sulfonylureas that inhibit NLRP3 activation in murine bone-marrow- derived macrophages in a potent, dose-dependent manner. Six of these compounds inhibited NLRP3 at nanomolar concentrations and can also stimulate insulin secretion from a murine pancreatic cell line (MIN6). These novel compounds possess unprecedented dual modes of action, paving the way for a new generation of sulfonylureas that may be useful as therapeutic candidates and/or tool compounds in T2D and its associated inflammatory complications.
- Hill, James R.,Coll, Rebecca C.,Sue, Nancy,Reid, Janet C.,Dou, Jennifer,Holley, Caroline L.,Pelingon, Ruby,Dickinson, Joshua B.,Biden, Trevor J.,Schroder, Kate,Cooper, Matthew A.,Robertson, Avril A. B.
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p. 1449 - 1457
(2017/09/18)
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- N,N'-bis-substituted aryl thiourea derivatives and synthetic method and application thereof
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The invention discloses N,N'-bis-substituted aryl thiourea derivatives which are a series of compounds simultaneously containing various substituted aromatic ring structures and asymmetric substituted thiourea structures and are all novel structural compounds which are not reported in the literature. The biological activity test analysis of all the target compounds includes determination of DPPH antioxidant activity and antiviral activity. Results indicate that, in general, the designed and synthesized compounds are novel in structures and have the antioxidant activity and the antiviral activity revealed for the first time. In addition, the unknown biological activity is not fully elucidated, and thus the compounds are expected to provide a certain material basis for further research and development of new drugs.
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Paragraph 0056; 0058; 0061; 0062
(2017/04/26)
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- Cu(II)-catalyzed decarboxylation/elimination of N-arylsulfonyl amino acids to primary aryl sulfonamides
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A novel protocol for CuO-catalyzed decarboxylation/elimination of N-arylsulfonyl amino acids was developed. It is the first example of using an accessible amino acid as an ammonia synthetic equivalent for the synthesis of primary aryl sulfonamides via oxidative decarboxylation/elimination reactions. The present protocol shows excellent functional group tolerance and provides an efficient method for the synthesis of primary aryl sulfonamides in excellent yields.
- Zhou, Liandi,Li, Xiaokang,Liu, Wei,Zhao, Yongli,Chen, Junmin
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p. 1299 - 1306
(2016/08/16)
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- SULFONYLUREAS AND RELATED COMPOUNDS AND USE OF SAME
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ABSTRACT The present invention provides for certain sulfonyl ureas and related compounds which have advantageous properties and show useful activity in the inhibition of activation of the NLRP3 inflammasome. Such compounds are useful in the treatment of a wide range of disorders in which the inflammation process, or more specifically the NLRP3 inflammasome, have been implicated as being a key factor.
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Page/Page column 128; 129
(2016/09/15)
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- HEPARAN SULFATE BIOSYNTHESIS INHIBITORS FOR THE TREATMENT OF DISEASES
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Described herein are compounds of Formula I, methods of making such compounds, pharmaceutical compositions and medicaments containing such compounds, and methods of using such compounds to treat or prevent diseases or conditions in need of inhibition of heparan sulfate biosynthesis.
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Paragraph 000792
(2016/05/02)
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- Discovery of a Series of 5,11-Dihydro-6H-benzo[e]pyrimido[5,4-b][1,4]diazepin-6-ones as Selective PI3K-δ/γ Inhibitors
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Dual inhibition of PI3K-δ and PI3K-γ is an established therapeutic strategy for treatment of hematological malignancies. Reported molecules targeting PI3K-δ/γ selectively are chemically similar and based upon isoquinolin-1(2H)-one or quinazolin-4(3H)-one scaffolds. Here we report a chemically distinct series of potent, selective PI3K-δ/γ inhibitors based on a 5,11-dihydro-6H-benzo[e]pyrimido[5,4-b][1,4]diazepin-6-one scaffold with comparable biochemical potency and cellular effects on PI3K signaling. We envisage these molecules will provide useful leads for development of next-generation PI3K-δ/γ targeting therapeutics.
- Ferguson, Fleur M.,Ni, Jing,Zhang, Tinghu,Tesar, Bethany,Sim, Taebo,Kim, Nam Doo,Deng, Xianming,Brown, Jennifer R.,Zhao, Jean J.,Gray, Nathanael S.
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supporting information
p. 908 - 912
(2016/10/22)
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- A general iodine-mediated synthesis of primary sulfonamides from thiols and aqueous ammonia
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A general and efficient methodology for preparing primary sulfonamides has been developed. In the presence of iodine as the catalyst and TBHP (70% in water) as the oxidant, a wide range of primary sulfonamides were prepared from the corresponding thiols and aqueous ammonia in moderate to good yields.
- Feng, Jian-Bo,Wu, Xiao-Feng
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supporting information
p. 6951 - 6954
(2016/07/30)
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- Sulfonamide formation from sodium sulfinates and amines or ammonia under metal-free conditions at ambient temperature
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A novel, practical and highly efficient method for the construction of a variety of sulfonamides mediated by I2 was demonstrated. The reaction proceeds readily at room temperature using a variety of sodium sulfinates and amines or ammonia in water in a metal-, base-, ligand-, or additive-free protocol. Primary, secondary and tertiary sulfonamides were obtained in good to excellent yields with a broad range of functional group tolerability. This journal is
- Yang, Kai,Ke, Miaolin,Lin, Yuanguang,Song, Qiuling
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supporting information
p. 1395 - 1399
(2015/03/18)
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- Natural Indian Natrolite zeolite-supported Cu nanoparticles: A new and reusable heterogeneous catalyst for N-arylation of sulfonamides with boronic acids in water under ligand-free conditions
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We report here on the preparation of primary sulfonamides and efficient, easily recoverable and reusable copper nanoparticles supported on natural Indian Natrolite zeolite as a catalyst for arylation of sulfonamides with arylboronic acids in water. The catalyst was characterized using the powder XRD, SEM, EDS and FT-IR spectroscopy. The significant advantages of this methodology are high yields, elimination of organic solvents, and simple work-up procedure. The catalyst was easily isolated from the reaction mixture and reused with no significant loss in its activity.
- Azarifar, Davood,Soleimanei, Fatemeh
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p. 12119 - 12126
(2014/03/21)
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- Ruthenium trichloride catalyzed synthesis of 2,3-unsaturated-N-glycosides via Ferrier azaglycosylation
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An efficient, economical and mild protocol for the synthesis of 2,3-unsaturated-N-glycosides has been developed using ruthenium(III) chloride. The Ferrier azaglycosylation of glycals with various N-nucleophiles such as sulfonamides, benzamides, carbamates and N-substituted sulfonamides proceeded smoothly to afford the corresponding 2,3-unsaturated-N-glycosides or ‘N-pseudoglycals’ in good yields (64–98%). High α-anomeric selectivity was observed with N-substituted sulfonamides such as N-benzyl or N-phenyl sulfonamides under similar conditions.
- Reddy, Thurpu Raghavender,Chittela, Sravanthi,Kashyap, Sudhir
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supporting information
p. 9224 - 9229
(2017/09/08)
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- C → N and N → C solution phase peptide synthesis using the N-acyl 4-nitrobenzenesulfonamide as protection of the carboxylic function
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In this paper we describe a solution phase peptide synthesis strategy using the 4-nitrobenzenesulfonamido/N-methyl-4-nitrobenzenesulfonamido group as a protecting/activating system of the carboxyl function. The 4- nitrobenzenesulfonamido group is stable during peptide chain elongation (Fmoc chemistry). The N-aminoacyl or N-dipeptidyl-4-nitrobenzensulfonamides, when activated by methylation, can be easily coupled with another amino acid or reconverted into the free-carboxyl function amino acids or peptides. This activatable protecting group allows both the C → N and the N → C direction solution phase peptide synthesis. We also verified that the absolute configuration at the chiral centers does not change during the coupling reactions. This journal is The Royal Society of Chemistry 2013.
- De Marco, Rosaria,Spinella, Mariagiovanna,De Lorenzo, Anna,Leggio, Antonella,Liguori, Angelo
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p. 3786 - 3796
(2014/03/21)
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- Synthesis of diazonium (perfluoroalkyl) benzenesulfonylimide zwitterions
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The synthesis and properties of diazonium (perfluoroalkyl) benzenesulfonylimide (PFSI) zwitterions are described. The general procedures for the diazonium PFSI zwitterions involve three steps: (1) a coupling reaction, (2) a reduction reaction and (3) a diazotization reaction. These novel diazonium PFSI zwitterions represent a new versatile class of remarkably stable diazonium materials with potential for modification of carbon supports for electrodes in proton exchange membrane (PEM) fuel cells.
- Mei, Hua,Vanderveer, Don,Desmarteau, Darryl D.
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- One-step synthesis of racemic α-amino acids from aldehydes, amine components, and gaseous CO2 by the aid of a bismetal reagent
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α-Amino acids are essential resources for human life and are highly useful as building blocks for organic synthesis. The core framework of an α-amino acid can be divided into three basic components: an aldehyde, an amine, and carbon dioxide (CO2). We report herein that a one-step synthesis of α-amino acids has been successfully achieved from these three basic and inexpensive chemicals with a single operation, in which the mixture of an aldehyde, a sulfonamide, and gaseous CO2 was heated at 100 °C in the presence of Bu3Sn-SnBu3 and CsF. In this one-pot sequential protocol, two important intermediates (imine and α-amino stannane) are involved and the stannyl anion generated in situ plays a crucial role, particularly for the efficient stannylation of the imine in the presence of proton sources and for promoting retrostannylation of the undesired α-alkoxy stannane owing to its high stability and tolerance of the presence of proton sources. This methodology enabled the synthesis of a wide range of racemic arylglycine derivatives in high yields. Go retro! α-Amino acids are essential resources for human life and are highly useful as building blocks for organic synthesis. The core framework of an α-amino acid is retrosynthesized to an aldehyde, an amine, and carbon dioxide. A one-step synthesis of α-amin Copyright
- Mita, Tsuyoshi,Higuchi, Yuki,Sato, Yoshihiro
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supporting information
p. 1123 - 1128
(2013/02/23)
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- Iodine-catalyzed aminosulfonation of hydrocarbons by imidoiodinanes. a synthetic and mechanistic investigation
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The amino-functionalization of a range of benzylic and some aliphatic saturated and unsaturated hydrocarbons by reaction with imido-iodinanes (PhI=NSO2Ar) is catalyzed by I2 under operationally simple and mild conditions. The first examples of 1,2-functionalization of unactivated C-H bonds using imido-iodinanes as aminating agents are reported. Mechanistic investigations, including Hammett analysis, kinetic isotope effects, a cyclopropane clock experiment, and stereoselectivity tests, are indicative of a stepwise pathway in C-N bond formation. Investigation into the nature of the active aminating species has led to the isolation of a novel aminating agent formulated as (ArSO2N)xIy (x = 1, y = 2; or x = 3, y = 4).
- Lamar, Angus A.,Nicholas, Kenneth M.
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supporting information; experimental part
p. 7644 - 7650
(2010/12/25)
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- Mechanistic study of oxidation of sulfacetamide by diperiodatocuprate(III) in aqueous alkaline medium
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The oxidation of sulfacetamide, a sulfonamide drug, by alkaline diperiodatocuprate(III) has been studied at 298 K and at constant ionic strength. The reaction is first order in diperiodatocuprate(III) and has less than unit order in sulfacetamide concentration. The rate constants increase with increase in alkali concentration and decrease with increase in periodate concentration. A mechanism has been proposed wherein monoperiodatocuprate(III) is the active species. The reaction constants involved in the different steps of the mechanism and the activation parameters for the slow step have been computed.
- Naik,Kulkarni,Chimatadar,Nandibewoor
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scheme or table
p. 1666 - 1670
(2009/06/28)
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- Scandium triflate as an efficient and recyclable catalyst for the deprotection of tert-butyl aryl sulfonamides
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A mild and efficient method for deprotection of tert-butyl sulfonamide groups utilizing Sc(OTf)3 as deprotecting reagent has been developed. A variety of tert-butyl aryl sulfonamides used under these conditions gave the corresponding primary sulfonamides in high yields. The Lewis acid catalyst could be fully recovered and reused with maintained activity after the reactions. Copyright Taylor & Francis, Inc.
- Mahalingam,Wu, Xiongyu,Wan, Yiqian,Alterman, Mathias
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p. 417 - 425
(2007/10/03)
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- Advantages of the Ns group in the reactions of N1-SO 2R inosines with benzylamine and with 15NH3
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The reactivity of N1-alkylsulfonyl- and N1- arylsulfonyl-2′,3′,5′-tri-O-acetylinosine with benzylamine and with 15NH3, regarding the attack on C2, has been shown to be in the order CF3SO2 (Tf) > 2,4-(NO 2)2C6H3SO2 (DNs) ≥ 4-NO2C6H4SO2 (pNs) ≈ C 6F5SO2 (PFBs) > 2-NO2C 6H4SO2 (Ns) ? CH3SO2 (Ms) > 4-CH3C6H4SO2 (Ts) > 2,4,6-(CH3)3C6H2SO2 (Mts). In spite of its intermediate reactivity, the Ns group is the most appropriate, since in this case the formation of by-products is minimised during the ring-opening and ring-closing steps of the process. Another advantage of the Ns group is thus disclosed.
- Terrazas, Montserrat,Ariza, Xavier,Vilarrasa, Jaume
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p. 5127 - 5130
(2007/10/03)
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- Novel N-dealkylation of N-alkyl sulfonamides and N,N-dialkyl sulfonamides with periodic acid catalyzed by chromium(III) acetate hydroxide
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Chromium(III) acetate hydroxide has been found to be an efficient catalyst for N-dealkylation of N-alkyl sulfonamides and N,N-dialkyl sulfonamides to furnish sulfonamides in good to excellent yields with periodic acid in acetonitrile at room temperature.
- Xu, Liang,Zhang, Suhong,Trudell, Mark L.
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p. 1901 - 1904
(2007/10/03)
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- Unprecedented observation of sulfonamides in the transesterification of N-unsubstituted carbamates with sulfonyl chlorides
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Sulfonamides have been identified as by-products in the base-mediated transesterification of N-unsubstituted carbamates with sulfonyl chlorides to give the corresponding sulfonates. A proposed mechanism and the synthesis of hindered 2,6-disubstituted arylsulfonates via this method are also reported.
- Dauvergne, Jér?me,Wellington, Kevin,Chibale, Kelly
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- BIFUNCTIONAL HETEROCYCLIC COMPOUNDS AND METHODS OF MAKING AND USING SAME
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The invention provides a family of bifunctional heterocyclic compounds useful as anti-infective, anti-proliferative, anti-inflammatory, and prokinetic agents. The invention also provides methods of making the bifunctional hetercyclic compounds, and methods of using such compounds as anti-infective, anti-proliferative agents, anti-inflammatory, and/or prokinetic agents.
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Page/Page column 264-265
(2010/02/06)
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- Boron trichloride as an efficient and selective agent for deprotection of tert-butyl aryl sulfonamides
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A fast, mild and selective method for deprotection of tert-butyl aryl sulfonamides utilizing BCl3 as deprotection reagent has been developed. A variety of tert-butyl aryl sulfonamides used under these conditions gave the corresponding primary sulfonamides in high yields. The method does not cleave methoxy groups and prevents incorporation of tert-butyl groups onto electron-rich aromatic rings.
- Wan, Yiqian,Wu, Xiongyu,Kannan, Mahalingam A.,Alterman, Mathias
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p. 4523 - 4525
(2007/10/03)
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- Catalytic asymmetric heterogeneous aziridination of styrene using CuHY: Effect of nitrene donor on enantioselectivity
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The copper-catalysed aziridination of styrene with copper-exchanged zeolite Y (CuHY) and copper(II) triflate (trifluoromethanesulfonate) (Cu(OTf)2) as catalysts is described in detail. Two nitrene donors, [N-(p-tolylsulfonyl)imino)]phenyliodinane (PhI=NTs) and [N-(p-nitrophenylsulfonyl)imino]phenyliodinane (PhI=NNs) are compared. Modification of the catalyst with bis(oxazolines) affords enantioselective catalysts and a range of chiral bis-(oxazolines) has been studied. The ratio of nitrene donor to styrene is shown to be an important factor controlling both the yield and ee of aziridine formed. The best results are obtained with PhI=NNs; ee, ≥ 90%, together with high yields (≥ 85%), can readily be achieved with this nitrene donor using acetonitrile as solvent. Addition of the nitrene donor over a period of time, rather than all at the start of the reaction, is shown to enhance the yield of the aziridine but the ee is significantly decreased for both the homogeneous and the heterogeneous catalysts. Experiments in which the breakdown products of the nitrene donor, iodobenzene and the corresponding sulfonamide, are added at the star of the reaction show that a complex interplay exists at the copper active site between the reactants, products, chiral modifier and the solvent. However, the heterogeneous catalyst, CuHY, is found to give enhanced enantioselection for a range of bis(oxazolines) compared to the homogeneous catalyst, and the effect is considered to be due to the confinement of the catalyst within the micropores of the zeolite.
- Taylor, Sophia,Gullick, John,McMorn, Paul,Bethell, Donald,Page, Philip C. Bulman,Hancock, Frederick E.,King, Frank,Hutchings, Graham J.
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p. 1714 - 1723
(2007/10/03)
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- Synthesis and properties of N-(2,2,2-trichloroethylidene)- and N-(2,2,2-trichloroethyl)nitrobenzenesulfonamides
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Highly reactive N-(2,2,2-trichloroethylidene)nitrobenzenesulfonamides were synthesized by reaction of N,N-dichloronitrobenzenesulfonamides with trichloroethylene. Reactions of N-(2,2,2-trichloroethylidene)nitrobenzenesulfonamides with oxygen and nitrogen nucleophiles gave products of addition at the double C=N bond; with arenes and haloarenes, the corresponding C-amidoalkylation products were obtained.
- Rozentsveig,Levkovskaya,Rybalova,Mirskova
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- The rhodium(II)-catalyzed aziridination of olefins with {[(4- nitrophenyl)sulfonyl]imino}phenyl-λ3-iodane
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The aziridination of olefins with {(4- nitrophenylsulfonyl)imino}phenyl-λ3-iodane, NsN=IPh (1c), in the presence of [Rh2(OAc)4] proceeds in yields of up to 85% when the olefin is used in large excess. Under optimized conditions, styrene (4a) is aziridinated with 1 equiv. of NsN=IPh (1c) in 64% yield with 2 mol% of catalyst. The aziridines derived from electron-rich olefins undergo ring-opening under the conditions of the aziridination and afford rearrangement products or pyrrolidines. The aziridination is sterospecific with 1,2-dialkyl- and 1,2-arylalkyl- disubstituted olefins, but nonstereospecific with stilbene. The ρ-value for aziridination of substituted styrenes iS -0.61. No ring-opened products are observed upon aziridination of vinylcyclopropanes. In the presence of chiral Rh(II) catalysts, the aziridination is enantioselective, affording an ee of 73% with cis-β-methylstyrene (4k) and Pirrungs [Rh2{(R)-(-)-bnp}4] catalyst. The experimental results are consistent with a one-step mechanism for transfer of the nitrenoid moiety from the catalyst to the olefin.
- Müller, Paul,Baud, Corine,Jacquier, Yvan
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p. 738 - 750
(2007/10/03)
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- Radical-chain reactions of sulfonyl azides and of ethyl azidoformate with allylstannanes: Homolytic allylation at nitrogen
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4-Methylbenzenesulfonyl azide reacts with allyltriphenylstannane (ATPS) in refluxing benzene, in the presence of 2,2′-azobis(2-methylpropionitrile) as initiator, to give N-allyl-4-methylbenzenesulfonamide in good yield after hydrolytic work-up. Small amounts of allyl 4-methylphenyl sulfone were also formed. The reaction follows a free-radical chain mechanism which involves competitive addition of Ph5Sn? to Na and to Nc of the azido group in ArSO2NaNbNc. Addition to Na followed by loss of nitrogen gives ArSO2NSnPh3, the precursor of the N-allylarenesulfonamide, while addition to Nc leads to the formation of ArSO2 and thence to the allyl aryl sulfone. Allyltrimethylstannane behaves in a similar way to ATPS, but allyltributylstannane gives only a low yield of N-allylarenesulfonamide and the major product is the unsubstituted sulfonamide MeC6H4SO2NH2, which results because the radical ArSO2NSnBu3 undergoes intramolecular 1,5-hydrogen-atom transfer in preference to adding to the allylstannane. 2-Methylallyltriphenylstannane reacts in an analogous way to ATPS, but allylstannanes containing non-terminal double bonds do not react successfully. The arenesulfonyl azides 4-XC6H4SO2N3 (X = H, MeO, F) react in a similar way to tosyl azide, but the reaction is very sluggish when X = NO2? With 1-octanesulfonyl azide, reaction with Ph3Sn? is much less selective and products arising from attack at Na and Nc are formed in comparable yields. Ethyl azidoformate reacts with allylstannanes in a similar manner to, although more slowly than, tosyl azide and gives good yields of the corresponding allylic carbamates.
- Dang, Hai-Shan,Roberts, Brian P.
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p. 1493 - 1498
(2007/10/03)
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- Effects of medium and substituents on dissociation of 4,4′-disubstituted bis(benzenesulfon)imides
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Ten 4,4′-disubstituted bis(arenesulfon)imides of the general formula XC6H4SO2NHSO2C6H 4X have been synthesized and their structures confirmed by their 1H NMR spectra. Elemental analyses are presented for the compounds not yet described. The dissociation constants of these model substances have been measured potentiometrically in pyridine, dimethylformamide, methanol, ethanol, propylene carbonate, acetone, acetonitrile, 1,2-dichloroethane and tetramethylene sulfone. The pKHA values obtained have been correlated with three sets of the Hammett substituent constants and the results have been used to discuss the solvent and substituent effects on the dissociation of the compounds studied. Sulfonimides with electron-acceptor substituents behave as rather strong acids in some solvents (pyridine, dimethylformamide, methanol and ethanol), whereas normal substituent dependences are found in other solvents. The experimental data have also been interpreted with the help of the statistical methods based on latent variables. From the calculations it follows that only the first principal component, which correlates well with the substituent constant sets adopted, is statistically significant in describing the substituent effect on the acid-base process studied.
- Ludwig, Miroslav,Stverka, Pavel
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p. 1205 - 1214
(2007/10/03)
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- Structure-activity considerations in kinetics and mechanism of chlorine exchange between chloramine-T and secondary amines
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To study the mechanism of N-chlorination of secondary amines by chloramine-T, the kinetics of the reactions of some aromatic-substituted analogues of N-chlorobenzenesulfonamide with various secondary amines were determined. The importance of amine basicity and reactivity of the N-Cl bond of the N-chlorobenzenesulfonamide was also assessed. The results indicate that a mechanism involving the un-ionized species of both reactants (i.e., a molecular mechanism), rather than an ionic mechanism, is operating and that the reaction most likely proceeds via a six-membered-ring transition state that incorporates a water molecule.
- Dannan,Hussain,Crooks,Dittert
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p. 657 - 660
(2007/10/02)
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- Herbicidally active phenoxyalkanecarboxylic acid derivatives
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A compound of the formula: STR1 wherein Q1 is CH or N; R is H or C1 -C5 alkyl; X is H, halogen, CF3, or NO2 ; Y is H or halogen; Z is --O-- or --NH--; A is STR2 wherein Q2, and Q3 are each CH or N; R1 and R2 are each H, C1 -C5 alkyl, C1 -C5 alkoxy, or C2 -C6 alkxoycarobnyl; R3, R4, and R5 are each H or C1 -C5 alkyl; R6 is H, halogen, or C1 -C5 alkyl; R7, R8, R9, and R10 are each H or C1 -C5 alkyl; R11 is H, C1 -C5 alkyl, C1 -C5 alkoxy, C2 -C6 alkenyl, C6 -C10 aryl, C7 -C15 aryloxyalkyl, or C7 -C15 aralkyl; R12 and R13 are each H or C1 -C5 alkyl; R14 is C1 -C5 alkyl, C2 -C6 alkenyl, C5 -C10 aryl, or C7 -C15 aralkyl; or R13 and R14 taken together form C3 -C4 alkylene, V1 and V2 are each H, halogen, NO2, CN, or CF3 ; V3 is halogen or CF3 ; W1 is --O-- or --NH--; W2 is --(CH2)n -- wherein n is 0 or 1, or CO; X1 is halogen, or a salt thereof, which is effective as a herbicidal agent.
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- REACTION OF ORGANIC AZIDES WITH UNSATURATED COMPOUNDS. IX. PRODUCTS FROM REARRANGEMENT OF 1-ARYLSULFONYL-4,4,5-TRIMETHYL-5-ETHOXY-1,2,3-TRIAZOLINES
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Ethyl N-arylsulfonyl-2,2-dimethylpropanimidates and N-(1,1-dimethyl-2-ethoxy-2-propenyl)arenesulfonamides are obtained in the reaction of arylsulfonyl azides with 2-methyl-3-ethoxy-2-butene.Thus, the intermediate 1-arylsulfonyl-4,4,5-trimethyl-5-ethoxy-1,2,3-triazolines not only rearrange to the imidates but are also converted into unstable 1-arylsulfonyl-2,2,3-trimethyl-3-ethoxyaziridines, which isomerize to the N-substituted arenesulfonamides.
- Semenov, V. P.,Mishin, M. A.,Ogloblin, K. A.
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p. 2149 - 2153
(2007/10/02)
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- REACTION OF ORGANIC AZIDES WITH UNSATURATED COMPOUNDS. VIII. REARRANGEMENT OF Δ2-1,2,3-TRIAZOLINES, OBTAINED FROM ARENESULFONYL AZIDES AND β,β-DIMETHYL-4-METHOXYSTYRENE BY AN ARYL SHIFT
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2-Methyl-2-propanal was found in the products from the reaction of arenesulfonyl azides with β,β-dimethyl-4-methoxystyrene after hydrolysis.This indicates that 1-arylsulfonyl-4,4-dimethyl-5--Δ2-1,2,3-triazolenes rearrange by an aryl and not a hydride shift.
- Semenov, V. P.,Andreeva, T. D.,Ogloblin, K. A.
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p. 195 - 198
(2007/10/02)
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- THERMAL Z,E-ISOMERIZATION OF IMINES. VI. N-ARYLSULFONYLIMINES OF ACETONE AND 2,6-DI-tert-BUTYL-1,4-BENZOQUINONE
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The thermal topomerization of acetone N-arylsulfonylimines and 2,6-di-tert-butyl-1,4-benzoquinone N-arylsulfonyl-4-monoimines was studied by the dynamic PMR method.The inversion mechanism of the topomerization of the N-arylsulfonylimines was established on the basis of an investigation into the electronic and steric effects of substituents at the sulfur atom on the sizes of the barriers to topomerization.The effect of nN-3dS and nN-?c-s* interactions and the induction effect of the arylsulfonyl group on the sizes of the barriers to inversion at the nitrogen atom are considered.The reduction of the barriers to inversion in the N-arylsulfonylimines with increase in the electron-withdrawing characteristics of the para substituents in the aryl ring is largely determined by the increase in the nN-3dS interaction.
- Prosyanik, A.V.,Kol'tsov, N.Yu.,Romanchenko, V.A.,Belov, V.V.,Burmistrov, K.S.,Loban', S.V.
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p. 335 - 342
(2007/10/02)
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- Multinuclear NMR Study of Variously Substituted Sulphonamides and Sulphinamides
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13C, 15N and 17O NMR chemical shifts, and also 1J(CH) and 1J(NH) values, have been determined for variously substituted sulphonamides and some sulphinamides, either neat or in acetone or dimethyl sulphoxide solution.The effect of benzene ring substitutens on the chemical shifts of nitrogen and oxygen nuclei is slight, but N-substitution changes the shielding of both nuclei.Generally, an N-methyl substituent shields an amide nitrogen and an N,Ndimethyl substituent gives further slight shielding.On the other hand, an N-phenyl substituent deshilds the nitrogen strongly, but the deshielding effect of an N,N-diphenyl substituent is markedly smaller.The sulphonyl oxygens are deshilded relative to the sulphinyl oxygens, and N-methyl and N,N-dimethyl substituents shild the oxygen nucleus.The effect of N-phenyl and N,N-diphenyl substituents on the shielding of the oxygen atoms of the sulphonyl group is slight.The direct 1J(CH) coupling constants are similar, but they are characteristic of different type of sulphur amides.The 1J(NH) values are of the same order of magnitude for sulphonamides and sulphinamides, but are clearly smaller for N-unsubstituted amides than for N-substituted compounds.KEY WORDS Sulphonamide Sulphinamide Multinuclear NMR
- Ruosteuso, P.,Haekkinen, A.-M.,Mattila, T.
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p. 189 - 193
(2007/10/02)
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- DISSOCIATION OF SUBSTITUTED BENZENESULPHONAMIDES IN WATER, METHANOL AND ETHANOL
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Thirteen monosubstituted arylsulphonamides (XC6H4SO2NH2) and two 3,4-disubstituted arylsulphonamides (X2C6H3SO2NH2) have been synthetized and their dissociation constants have been measured by potentiometric titration in water, methanol, and ethanol.The Hammett substitution dependences have been calculated for all the media, and changes in the reaction constants due to transition from water to alcohols are discussed in confrontation with analogous dependences of benzoic acids.The reaction constant ρ found in methanol is lower than that in water.The dissociation constants have been treated by the method of the principal components and by multiple linear regression.
- Ludwig, Miroslav,Pytela, Oldrich,Kalfus, Karel,Vecera, Miroslav
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p. 1182 - 1192
(2007/10/02)
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