- Characterization of the conductivity of organic thiols by field emission microscopy and field emission spectroscopy
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The conducting properties of two organic thiols (5-mercapto-2,2′-bithiophene and 4-mercaptobiphenyl) deposited by the self-assembly method on Pt tips have been characterized in ultrahigh vacuum by field emission microscopy and spectroscopy. It was shown that these two molecular species can be successfully adsorbed from solution on the Pt tip. The presence of the molecules causes a large decrease in the required field emission voltages by a factor of ~3-5. Measurement of the total energy distributions of the emitted electrons showed that the electrons are emitted from a narrow band which is not pinned at the Fermi level but which shifts to lower energy with increased applied field. The molecules thus appear more like an insulator than a conductor. Significant current-induced heating of the molecules was found: for example, ΔT ≈ 80 K for 0.3 nA. Taken together these properties pose problems for the use of these and similar one-dimensional molecules as current-carrying connections in proposed nanoscale electronic applications. However, when used in the subpicoampere range, the current through the wire may be sustainable and dissipation small. In general, these experiments open a door to exploring other molecules.
- Purcell,Garcia,Binh, Vu Thien,Jones II,Tour
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- Effects of hindered internal rotation on packing and conductance of self-assembled monolayers
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Self-assembled monolayers of 4-thiobiphenyl and 2-thiophenanthrene molecules on Au{111} were probed using scanning tunneling microscopy (STM) to investigate their assembled order, to measure the conductance through them, and to determine what molecular features are necessary for molecules to exhibit conductance switching. The 4-thiobiphenyl molecules assemble into two distinct packing structures, whereas no order is observed for 2-thiophenanthrene. Both molecules show rectifying behavior, but although 4-thiobiphenyl is more conductive at positive sample biases, 2-thiophenanthrene is more conductive at negative sample bias. Individual molecules of each type were also inserted into alkanethiol SAMs and tracked over several hours to investigate the conductance states of each molecule. Both molecules exhibit two conductance states, indicating that internal ring rotation is not required for conductance switching.
- Dameron, Arrelaine A.,Ciszek, Jacob W.,Tour, James M.,Weiss, Paul S.
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- Synthesis, characterization, and application of palladium-dithizone immobilized on magnetic nanoparticles as an efficient and recoverable catalyst for Suzuki type coupling reactions
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A novel, magnetically separable catalyst was synthesized by the immobilization of Pd on magnetite nanoparticles (MNPs) coated with dithizone. The activity of this catalyst was examined for the synthesis of various biaryls via the C-C coupling reaction of aryl halides and sodium tetraphenylborate or phenylboronic acid under mild reaction conditions. Fe3O4/SiO2-DTZ-Pd was characterized by transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, vibrating sample magnetometer, and scanning electron microscopy.
- Ghorbani-Choghamarani, Arash,Rabiei, Hossein
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Read Online
- Discovery of 3,5-Dimethyl-4-Sulfonyl-1 H-Pyrrole-Based Myeloid Cell Leukemia 1 Inhibitors with High Affinity, Selectivity, and Oral Bioavailability
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Myeloid cell leukemia 1 (Mcl-1) protein is a key negative regulator of apoptosis, and developing Mcl-1 inhibitors has been an attractive strategy for cancer therapy. Herein, we describe the rational design, synthesis, and structure-activity relationship study of 3,5-dimethyl-4-sulfonyl-1H-pyrrole-based compounds as Mcl-1 inhibitors. Stepwise optimizations of hit compound 11 with primary Mcl-1 inhibition (52%@30 μM) led to the discovery of the most potent compound 40 with high affinity (Kd = 0.23 nM) and superior selectivity over other Bcl-2 family proteins (>40,000 folds). Mechanistic studies revealed that 40 could activate the apoptosis signal pathway in an Mcl-1-dependent manner. 40 exhibited favorable physicochemical properties and pharmacokinetic profiles (F% = 41.3%). Furthermore, oral administration of 40 was well tolerated to effectively inhibit tumor growth (T/C = 37.3%) in MV4-11 xenograft models. Collectively, these findings implicate that compound 40 is a promising antitumor agent that deserves further preclinical evaluations.
- Zhu, Peng-Ju,Yu, Ze-Zhou,Lv, Yi-Fei,Zhao, Jing-Long,Tong, Yuan-Yuan,You, Qi-Dong,Jiang, Zheng-Yu
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p. 11330 - 11353
(2021/08/24)
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- COMPOUNDS AND METHODS FOR TREATING OXALATE-RELATED DISEASES
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Disclosed herein are compounds and compositions for modulating glycolate oxidase, useful for treating oxalate-related diseases, such as hyperoxaluria, where modulating glycolate oxidase is expected to be therapeutic to a patent in need thereof. Methods of modulating glycolate oxidase activity in a human or animal subject is also provided.
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Paragraph 0248; 0279
(2019/09/12)
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- SINGLE-STEP SYNTHESIS METHOD OF ARYL THIOL AND APPLICATION THEREOF
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The present invention relates to a single-step synthesis method of aryl thiol, and more specifically, to a method of synthesizing aryl thiol in a single-step by making aryl halide react with alkane dithiol in the presence of a transition metal catalyst. According to the present invention, a single-step synthesis method using the transition metal catalyst, the synthesis method which is capable of synthesizing aryl thiol from aryl halide at a high yield, can be provided. Various aryl halides may be applied to the synthesis method. Further, the synthesis method has advantages that an easily usable reagent may be used, operations are simple, and reactions can be performed under mild conditions. In addition, the synthesized aryl thiol may be used in the synthesis of advanced molecules such as diaryl sulfides and benzothiophenes.COPYRIGHT KIPO 2017
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Paragraph 0032; 0033; 0063; 0067; 0068; 0070
(2017/09/02)
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- Preparation method for synthesizing thiophenol compound based on sodium sulfide nonahydrate
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The invention provides a preparation method for synthesizing a thiophenol compound based on sodium sulfide nonahydrate. In an inert gas protective atmosphere, substituted iodobenzene and a sulfhydrylation reagent are added into an aprotic polar solvent, then a copper salt catalyst and a ligand compound are orderly added into the solution, the mixed solution undergoes a reaction at a temperature of 90 to 120 DEG C for 12-24h, and the reaction solution is cooled to the room temperature and is acidized so that the product is obtained. The preparation method has the advantages of simple reaction conditions, good compatibility of functional groups, high yield and small environmental pollution. Thiophenol is an important intermediate for pharmaceutical chemical synthesis and has a very wide application range in fields of chemical raw materials, pesticides and medicines. The preparation method has a great use value and good social and economic benefits.
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Paragraph 0031; 0032
(2017/08/30)
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- Copper-Catalyzed Direct Synthesis of Aryl Thiols from Aryl Iodides Using Sodium Sulfide Aided by Catalytic 1,2-Ethanedithiol
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A copper-catalyzed direct and effective synthesis of aryl thiols from aryl iodides using readily available Na 2 S·9H 2 O and 1,2-ethanedithiol was described. A variety of aryl thiols were readily obtained in yields of 76-99%. In this protocol, Na 2 S·9H 2 O was used as ultimate sulfur source, and 1,2-ethanedithiol functioned as an indispensable catalytic reagent.
- Xue, Hongyu,Jing, Bing,Liu, Shasha,Chae, Junghyun,Liu, Yajun
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p. 2272 - 2276
(2017/10/06)
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- Palladium supported on modified magnetic nanoparticles: A phosphine-free and heterogeneous catalyst for Suzuki and Stille reactions
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An efficient magnetic nanoparticle-supported palladium (Fe3O4/SiO2-PAP-Pd) catalyst is reported for the Suzuki cross-coupling and Stille reactions. This method provides a novel and much improved modification of the Suzuki and Stille coupling reactions in terms of phosphine-free catalyst, short reaction time, clean reaction and small quantity of catalyst. Another important feature of this method is that the catalyst can be easily recovered from the reaction mixture and reused with no loss of its catalytic activity.
- Ghorbani-Choghamarani, Arash,Norouzi, Masoomeh
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p. 140 - 147
(2016/02/14)
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- Copper(II)-Catalyzed Single-Step Synthesis of Aryl Thiols from Aryl Halides and 1,2-Ethanedithiol
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A highly efficient transition metal-catalyzed single-step synthesis of aryl thiols from aryl halides has been developed employing copper(II) catalyst and 1,2-ethanedithiol. The key features are use of readily available reagents, a simple operation, and relatively mild reaction conditions. This new protocol shows a broad substrate scope with excellent functional group compatibility. A variety of aryl thiols are directly prepared from aryl halides in high yields. Furthermore, the aryl thiols are used in situ for the synthesis of more advanced molecules such as diaryl sulfides and benzothiophenes.
- Liu, Yajun,Kim, Jihye,Seo, Heesun,Park, Sunghyouk,Chae, Junghyun
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supporting information
p. 2205 - 2212
(2015/07/27)
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- Multiscale charge injection and transport properties in self-assembled monolayers of biphenyl thiols with varying torsion angles
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This article describes the molecular structure-function relationship for a series of biphenylthiol derivatives with varying torsional degree of freedom in their molecular backbone when self-assembled on gold electrodes. These biphenylthiol molecules chemisorbed on Au exhibit different tilt angles with respect to the surface normal and different packing densities. The charge transport through the biphenylthiol self-assembled monolayers (SAMs) showed a characteristic decay trend with the effective monolayer thickness. Based on parallel pathways model the tunneling decay factor β was estimated to be 0.27 A-1. The hole mobility of poly(3-hexylthiophene)-based thin-film transistors incorporating a biphenylthiol SAM coating the Au source and drain electrodes revealed a dependence on the injection barrier with the highest occupied molecular orbital (HOMO) level of the semiconductor. The possible role of the resistivity of the SAMs on transistor electrodes on the threshold voltage shift is discussed. The control over the chemical structure, electronic properties, and packing order of the SAMs provides a versatile platform to regulate the charge injection in organic electronic devices. Controlled charge injection! Biphenylthiols with different substituents between phenyl groups in the bridge position, once chemisorbed onto gold source-drain electrodes, can be used to vary the charge injection and electrical performances of organic thin-film transistors. By varying the torsion angle between the phenyl rings, one can introduce changes in packing densities and tilt angles of the molecules self-assembled on the electrode that play a direct role in influencing the charge transport through the molecular monolayer (see figure). Copyright
- Masillamani, Appan Merari,Crivillers, Nuria,Orgiu, Emanuele,Rotzler, Juergen,Bossert, David,Thippeswamy, Ramakrishnappa,Zharnikov, Michael,Mayor, Marcel,Samori, Paolo
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supporting information; experimental part
p. 10335 - 10347
(2012/10/08)
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- Palladium catalyzed synthesis of aryl thiols: Sodium thiosulfate as a cheap and nontoxic mercapto surrogate
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A Pd-catalyzed coupling reaction of ArBr/ArCl/ArOTf with sodium thiosulfate takes place in presence of Cs2CO3 at 80 °C. The reaction mixture is directly treated with Zn/HCl to afford aryl thiols in good to excellent yields.
- Yi, Jun,Fu, Yao,Xiao, Bin,Cui, Wei-Chen,Guo, Qing-Xiang
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experimental part
p. 205 - 208
(2011/02/26)
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- Copper-catalyzed coupling of thiourea with aryl iodides: The direct synthesis of aryl thiols
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A general, economical and efficient protocol for the direct copper-catalyzed coupling of thiourea with aryl iodides is developed and it will be potentially applied in large-scale industry as a preferred process.
- Qiao, Shu,Xie, Kun,Qi, Junsheng
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scheme or table
p. 1441 - 1443
(2011/01/04)
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- A general and efficient approach to aryl thiols: Cul-catalyzed coupling of aryl iodides with sulfur and subsequent reduction
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A Cul-catalyzed coupling reaction of aryl iodides and sulfur powder takes place in the presence of K2CO3 at 90 °C. The coupling mixture is directly treated with NaBH4 or triphenylphosphine to afford aryl thiols in good to
- Jiang, Yongwen,Qin, Yuxia,Xie, Siwei,Zhang, Xiaojing,Dong, Jinhua,Ma, Dawei
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supporting information; scheme or table
p. 5250 - 5253
(2009/12/28)
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- Practical thiol surrogates and protective groups for arylthiols for Suzuki-Miyaura conditions
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We have developed practical thiol surrogates and arylthiol protective groups for the Suzuki-Miyaura reaction. 2-Ethylhexyl-3-mercaptopropionate and 4-(2′-mercaptoethyl)pyridine were shown to be not only good thiol surrogates but also good protective groups for thiol. We have demonstrated toleration of these protective groups under aqueous Suzuki-Miyaura conditions.
- Itoh, Takahiro,Mase, Toshiaki
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p. 2203 - 2206
(2007/10/03)
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- Controlling molecular crystal polymorphism with self-assembled monolayer templates
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The control of crystal polymorphism is a long-standing issue in solid-state chemistry, which has many practical implications for a variety of commercial applications. At least four different crystalline forms of 1,3-bis(m- nitrophenyl) urea (MNPU), a clas
- Hiremath, Rupa,Basile, Joseph A.,Varney, Stephen W.,Swift, Jennifer A.
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p. 18321 - 18327
(2007/10/03)
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- Discovery of Small-Molecule Inhibitors of the ATPase Activity of Human Papillomavirus E1 Helicase
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The Boehringer Ingelheim compound collection was screened for inhibitors of the ATPase activity of human papillomavirus E1 helicase to develop antiviral agents that inhibit human papillomavirus (HPV) DNA replication. This screen led to the discovery of (biphenyl-4-sulfonyl)acetic acid 1, which inhibits the ATPase activity of HPV type 6 E1 helicase with a low micromolar IC50 value. A hit-to-lead exercise rapidly converted 1 into a low nanomolar lead series.
- Faucher, Anne-Marie,White, Peter W.,Brochu, Christian,Grand-Ma?tre, Chantal,Rancourt, Jean,Fazal, Gulrez
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- The synthesis of new 2,4-diaminofuro[2,3-d]pyrimidines with 5-biphenyl, phenoxyphenyl and tricyclic substitutions as dihydrofolate reductase inhibitors
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Nonclassical 2,4-diamino-5-substituted furo[2,3-d]pyrimidines 4a-i, 5a-b and 7a-f were synthesized as extended aromatic ring appended analogs of previously reported antifolates 1a-b. The extended aromatic system was designed to better interact with a phenylalanine residue (Phe69) of dihydrofolate reductase from the opportunistic pathogen Pneumocystis carinii to afford potent and selective inhibitors of Pneumocystis carinii dihydrofolate reductase. The target compounds were synthesized by nucleophilic displacement of 2,4-diamino-5-(chloromethyl)furo[2,3-d]pyrimidine 3 with the appropriate aromatic amine or thiol. The compounds were evaluated as inhibitors of dihydrofolate reductase from Pneumocystis carinii and Toxoplasma gondii, and their selectivity was determined using rat liver dihydrofolate reductase as the mammalian reference. In the C8-N9 bridged series, compound 4e, with a 3-(2-methoxydibenzofuran)- side chain, exhibited greatest potency and was more than 3 times as selective for Pneumocystis carinii dihydrofolate reductase compared to rat liver dihydrofolate reductase. Compounds 4b and 4c also exhibited selectivity. Compounds in the C8-S9 bridged series showed comparable potencies, and each showed higher selectivity for Pneumocystis carinii dihydrofolate reductase compared to rat liver dihydrofolate reductase.
- Gangjee,Dubash,Queener
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p. 935 - 942
(2007/10/03)
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- Process and intermediates for the preparation of oxazoline derivatives
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PCT No. PCT/US97/20798 Sec. 371 Date May 13, 1999 Sec. 102(e) Date May 13, 1999 PCT Filed Nov. 13, 1997 PCT Pub. No. WO98/22448 PCT Pub. Date May 28, 1998Arthropodicidal oxazoline derivatives and processes and intermediates for the preparation thereof are disclosed. The intermediates are racemic or enantiomerically enriched compounds having formula (I), wherein R and n are disclosed in the specification.
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- 2,6-diaryl pyridazinones with immunosuppressant activity
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A class of 2,6-diarylpyridazinones of general structural formula I have been identified that exhibit exhibit immunosuppressant activity with human T-lymphocytes, and are useful as an immunosuppressants. STR1 or a pharmaceutically acceptable salt, hydrate or crystal form thereof
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- 10-Thia-anthracenes. Part 3. A Re-examination of the Reaction of 9-Phenylthioxanthylium Salt and Phenyl-lithium
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Reaction of 9-phenylthioxanthylium salt (1) with phenyl-lithium afforded eight compounds, 9-phenyl- (2), 9,9-diphenyl- (3). 3,9-diphenyl (4), 3,9,9-triphenyl- (5), and 4,9,9-triphenyl-thioxanthene (6), 9,9'-diphenyl-9,9'-bithioxanthenyl (7), thioxanthone (8), and 9,9'-diphenyldithioxanth-9-yl peroxide (9).Their structures were determined by comparison with the authentic samples.Six samples, (3)-(6), 2,9,9-triphenyl- (30), 9-(biphenyl-4-yl)-9-phenylthioxanthene (31) were independently synthesized in order to determine the structures of two pairs of positional isomers, 3,4, and 5,6.A radical mechanism contributed to the reaction of compound (1) with phenyl-lithium.
- Hori, Mikio,Kataoka, Tadashi,Shimizu, Hiroshi,Ban, Masatoshi,Matsushita, Hitoshi
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p. 187 - 194
(2007/10/02)
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- A CONVENIENT SYNTHESIS OF AROMATIC THIOLS FROM UNACTIVATED ARYL HALIDES
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Aromatic thiols are obtained in good yields from unactivated aryl halides and excess MeSNa in HMPA.
- Testaferri, L.,Tingoli, M.,Tiecco, M.
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p. 3099 - 3100
(2007/10/02)
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