- Selective electrochemical oxidation of aromatic hydrocarbons and preparation of mono/multi-carbonyl compounds
-
A selective electrochemical oxidation was developed under mild condition. Various mono-carbonyl and multi-carbonyl compounds can be prepared from different aromatic hydrocarbons with moderate to excellent yield and selectivity by virtue of this electrochemical oxidation. The produced carbonyl compounds can be further transformed into α-ketoamides, homoallylic alcohols and oximes in a one-pot reaction. In particular, a series of α-ketoamides were prepared in a one-pot continuous electrolysis. Mechanistic studies showed that 2,2,2-trifluoroethan-1-ol (TFE) can interact with catalyst species and generate the corresponding hydrogen-bonding complex to enhance the electrochemical oxidation performance. [Figure not available: see fulltext.]
- Li, Zhibin,Zhang, Yan,Li, Kuiliang,Zhou, Zhenghong,Zha, Zhenggen,Wang, Zhiyong
-
p. 2134 - 2141
(2021/09/29)
-
- Identification of First-in-Class Inhibitors of Kallikrein-Related Peptidase 6 That Promote Oligodendrocyte Differentiation
-
Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS) that causes severe motor, sensory, and cognitive impairments. Kallikrein-related peptidase (KLK)6 is the most abundant serine protease secreted in the CNS, mainly by oligodendrocytes, the myelin-producing cells of the CNS, and KLK6 is assumed to be a robust biomarker of MS, since it is highly increased in the cerebrospinal fluid (CSF) of MS patients. Here, we report the design and biological evaluation of KLK6's low-molecular-weight inhibitors, para-aminobenzyl derivatives. Interestingly, selected hit compounds were selective of the KLK6 proteolytic network encompassing KLK1 and plasmin that also participate in the development of MS physiopathology. Moreover, hits were found noncytotoxic on primary cultures of murine neurons and oligodendrocyte precursor cells (OPCs). Among them, two compounds (32 and 42) were shown to promote the differentiation of OPCs into mature oligodendrocytes in vitro constituting thus emerging leads for the development of regenerative therapies.
- A?t Amiri, Sabrina,Deboux, Cyrille,Soualmia, Feryel,Chaaya, Nancy,Louet, Maxime,Duplus, Eric,Betuing, Sandrine,Nait Oumesmar, Brahim,Masurier, Nicolas,El Amri, Chahrazade
-
supporting information
p. 5667 - 5688
(2021/05/29)
-
- Copper-Catalyzed Methoxylation of Aryl Bromides with 9-BBN-OMe
-
A Cu-catalyzed cross-coupling reaction between aryl bromides and 9-BBN-OMe to provide aryl methyl ethers under mild conditions is reported. The oxalamide ligand BHMPO plays a key role in the transformation. Various functional groups on bromobenzenes are well tolerated, providing the desired anisole products in moderate to high yields.
- Li, Chen,Song, Zhi-Qiang,Wang, Dong-Hui,Wang, Jing-Ru
-
supporting information
p. 8450 - 8454
(2021/11/17)
-
- Aryl or heteroaryl methoxylation reaction method
-
The invention discloses an aryl or heteroaryl methoxylation reaction method. The method comprises the following steps: preparing a substrate. The coupling agent, ligand, solvent, catalyst and base are mixed homogeneously in an inert gas to give the aryl or heteroaryl methoxy compounds. Compared with a methoxylation reaction method in the prior art, the method has the advantages that the reaction system conditions are mild, the usage amount of the catalyst and the ligand is low to 5% of the amount of the substrate material, and the catalytic efficiency is improved. The method has better compatibility to different substrate expansion and discovery of aryl halides or heteroaryl halides with different functional groups. The yield of aryl or heteroaryl methoxy compounds prepared by the method disclosed by the invention is 36% - 89%.
- -
-
Paragraph 0141-0147
(2021/11/21)
-
- Regioselective Electrochemical Cyclobutanol Ring Expansion to 1-Tetralones
-
A mild electrochemical method for the regioselective preparation of 1-tetralones under environmentally friendly conditions from readily available cyclobutanols was developed. A series of aromatic- and heteroaromatic-fused 1-tetralones was accessed through ring expansion of the functionalized cyclobutanols via electrochemical generation of alkoxy radicals and intramolecular cyclization.
- Petti, Alessia,Natho, Philipp,Lam, Kevin,Parsons, Philip J.
-
supporting information
p. 854 - 858
(2021/01/12)
-
- Potential anti-neuroinflammatory NF-кB inhibitors based on 3,4-dihydronaphthalen-1(2H)-one derivatives
-
Nuclear factor kappa B (NF-кB) inhibition represents a new therapeutic strategy for the treatment of neuroinflammatory diseases. In this study, a series of 3,4-dihydronaphthalen-1(2H)-one (DHN; 6a-n, 7a-c) derivatives were synthesised and characterised by NMR and HRMS. We assessed the toxicity and anti-neuroinflammatory properties of these compounds and found that 6m showed the greatest anti-neuroinflammatory properties, with relatively low toxicity. Specifically, 6m significantly reduced reactive oxygen species production, down-regulated the expression of NOD-like receptor pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and caspase-1 and prevented lipopolysaccharide-stimulated BV2 microglia cells polarisation towards an M1 phenotype. Furthermore, 6m significantly decreased IκBα and NF-кB p65 phosphorylation, thus inhibiting the NF-кB signalling pathway. This suggests that 6m may be explored as a functional anti-neuroinflammatory agent for the treatment of inflammatory diseases in the central nervous system, such as multiple sclerosis, traumatic brain injury, stroke and spinal cord injury.
- Sun, Yue,Zhou, Yan-Qiu,Liu, Yin-Kai,Zhang, Hong-Qin,Hou, Gui-Ge,Meng, Qing-Guo,Hou, Yun
-
p. 1631 - 1640
(2020/08/19)
-
- Green synthesis method of medical intermediate benzocyclohexanone compound
-
The invention provides a green synthesis method of a benzocyclohexanone compound, and belongs to the technical field of organic synthesis. The method provided by the invention comprises the followingsteps: by taking 4-phenylbutyric acid as a raw material, firstly carrying out reflux reaction with oxalyl chloride in dichloromethane, carrying out vacuum evaporation to dryness to obtain a crude product of the 4-phenylbutyryl chloride compound, then dissolving the crude product in a solvent, adding a metal-doped modified molecular sieve catalyst to start reaction, and stirring the solution at different temperatures to carry out ring closing reaction, thereby obtaining the product; and after the reaction is finished, carrying out suction filtration, solvent washing, column chromatography purification and other operations to obtain the target product benzocyclohexanone compound. The synthesis method disclosed by the invention is environment-friendly in reaction and simple and convenient tooperate, the catalyst can be recycled, and the synthesis method is suitable for green synthesis of the benzocyclohexanone compound.
- -
-
-
- Green Organic Solvent-Free Oxidation of Alkylarenes with tert-Butyl Hydroperoxide Catalyzed by Water-Soluble Copper Complex
-
Different benzylic compounds were efficiently oxidized to the corresponding ketones with aqueous 70% tert-butyl hydroperoxide (TBHP) and the catalytic system composed of CuCl2.2H2O and 2,2'-biquinoline-4,4'-dicarboxylic acid dipotassium salt (BQC). The catalytic system CuCl2/BQC/TBHP allows obtaining high yields at room temperature under organic solvent-free conditions. The interest of this system lies in its cost effectiveness and its benign nature towards the environment. Benzylic tertbutylperoxy ethers and benzylic alcohols were observed and suggested as the reaction intermediates. Analysis of organic products by atomic absorption did not show any contamination with copper metal. In terms of efficiency, CuCl2/BQC system is comparable or superior to the most of the catalytic systems described in the literature and which are based on toxic organic solvent.
- Ajjou, Abdelaziz Nait,Rahman, Ateeq
-
p. 165 - 174
(2020/04/15)
-
- PROCESS FOR THE PREPARATION OF AGOMELATINE IN CRYSTALLINE FORM
-
The present invention pertains to a process for the preparation of polymorph form X of agomelatine, which comprises providing agomelatine, and crystallizing agomelatine in the presence of at least one of an acid and a salt thereof, and to a polymorph form of agomelatine.
- -
-
Page/Page column 38
(2019/05/02)
-
- Synthesis, crystal structures and anti-inflammatory activity of fluorine-substituted 1,4,5,6-Tetrahydrobenzo[ h]quinazolin-2-Amine derivatives
-
Two fluorine-substituted 1,4,5,6-Tetrahydrobenzo[h]quinazolin-2-Amine (BQA) derivatives, namely 2-Amino-4-(2-fluorophenyl)-9-methoxy-1,4,5,6-Tetrahydrobenzo[ h]quinazolin-3-ium chloride, (8), and 2-Amino-4-(4-fluorophenyl)-9-methoxy-1,4,5,6-Tetrahydrobenzo[h]quinazolin-3-ium chloride, (9), both C19H19-FN3O+-Cl-, were generated by Michael addition reactions between guanidine hydrochloride and the -,unsaturated ketones (E)-2-(2-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, C18H15FO2, (6), and (E)-2-(4-fluorobenzylidene)-7-methoxy-3,4-dihydronaphthalen-1(2H)-one, (7). Because both sides of -,unsaturated ketones (6) or (7) can be attacked by guanidine, we obtained a pair of isomers in (8) and (9). Single-crystal X-ray diffraction indicates that each isomer has a chiral C atom and both (8) and (9) crystallize in the achiral space group P21/c. The chloride ion, as a hydrogen-bond acceptor, plays an important role in the formation of multiple hydrogen bonds. Thus, adjacent molecules are connected through intermolecular hydrogen bonds to generate a banded structure. Furthermore, these bands are linked into an interesting 3D network via hydrogen bonds and - interactions. Fortunately, the solubilities of (8) and (9) were distinctly improved and can exceed 50 mg ml-1 in water or PBS buffer system (pH 7.4) at room temperature. In addition, the results of an investigation of anti-inflammatory activity show that (8) and (9), with o-and p-fluoro substituents, respectively, display more potential for inhibitory effects on LPS-induced NO secretion than starting ketones (6) and (7).
- Sun, Yue,Gao, Zhongfei,Wang, Chunhua,Hou, Guige
-
p. 1157 - 1165
(2019/08/13)
-
- Intramolecular Büchner reaction and oxidative aromatization with SeO2 or O2
-
Intramolecular Büchner reaction of 1-diazo-5-phenylpentan-2-ones followed by oxidation with SeO2 or O2 in the presence of silica gel regioselectively gave 8-formyl-1-tetralones or one-carbon-lacking 1-tetralones, respectively.
- Morita, Shunya,Yoshimura, Tomoyuki,Matsuo, Jun-ichi
-
p. 729 - 732
(2019/07/31)
-
- An Electrophilic Trifluoromethylthiolation of Silylenol Ethers and β-Naphthols with Diethylaminosulfur Trifluoride and (Trifluoromethyl)trimethylsilane
-
An efficient and general trifluoromethylthiolation of silylenol ethers and β-naphthols have been accomplished employing the combination of diethylaminosulfur trifluoride (DAST) and (trifluoromethyl)trimethylsilane (CF3TMS) as source of electrophilic trifluoromethylthio moiety for the synthesis of α-trifluoromethylthiolated carbonyl compounds and β-naphthols in good yields. Important features of this method include wide functional group tolerance and use of readily available DAST/CF3TMS. Potential of the methodology was demonstrated via the synthesis of α-trifluoromethylthiolated (+)-4-cholesten-3-one and naphthoquinone. (Figure presented.).
- Saravanan, Perumal,Anbarasan, Pazhamalai
-
supporting information
p. 2894 - 2899
(2018/08/17)
-
- Design, synthesis and biological evaluation of 3,4-dihydronaphthalen-1(2H)-one derivatives as Bcl-2 inhibitors
-
Abstract: A series of new 3,4-dihydronaphthalen-1(2H)-one derivatives (6a–f) were designed, and synthesized by the Claisen–Schmidt condensation reaction. Their structures were characterized by NMR, FTIR, and MS spectroscopy. Their antitumor activities against human neoplastic cell lines Hela, Hepg2, K562, THP-1, SW1990, MIA PaCa-2, NCI-H460 and SK-BR-3 by the MTT method exhibited obvious anticancer activities and their cytotoxicities for LO2 cell lines were lower than DOX, especially for 6b and 6d. The inhibition activities against the Bcl-2 protein for 6b was evaluated and the result shows that lipophilic 3,4-dimethoxybenzylidene and 3,4-dihydronaphthalen-1(2H)-one could bind slightly to the active pockets of the Bcl-2 protein.
- Wang, Fuli,Zhang, Rongxiang,Cui, Yong,Sheng, Liping,Sun, Yinping,Tian, Wei,Liu, Xiao,Liang, Shuzeng
-
p. 5933 - 5942
(2017/09/23)
-
- Highly enantioselective [3+2] coupling of cyclic enamides with quinone monoimines promoted by a chiral phosphoric acid
-
Enantioselective [3+2] coupling of cyclic enamides with quinone monoimines was realised using a chiral phosphoric acid as a catalyst. This transformation allowed for the synthesis of highly enantioenriched polycyclic 2,3-dihydrobenzofurans (up to 99.9% ee). The absolute configuration of one product was determined by an X-ray crystal structural analysis. We also found a possible mechanism for this reaction.
- Zhang, Minmin,Yu, Shuowen,Hu, Fangzhi,Liao, Yijun,Liao, Lihua,Xu, Xiaoying,Yuan, Weicheng,Zhang, Xiaomei
-
supporting information
p. 8757 - 8760
(2016/07/15)
-
- Method for synthesizing tetralone compound
-
The invention belongs to the technical field of organic compound synthesis, provides a method for synthesizing a tetralone compound, and aims at solving the problems that in an exiting tetralone compound synthesizing method, an expensive transition metal catalyst, such as a palladium catalyst, is needed, and a large quantity of oxidizing agent is needed during a reaction. Aryl is used for replacing cyclobutanol to serve as an initiator, under the action of a catalyst, an oxidizing agent and an additive, reacting is carried out for 1-8 h in a solvent at the temperature of 25 DEG C to 100 DEG C, and the tetralone compound is obtained. The method has the advantages that the reaction conditions are relatively moderate, cheap metal copper is adopted as the catalyst, ligand participation is not needed, and operation is easy, convenient and feasible.
- -
-
Paragraph 0025; 0026
(2016/10/07)
-
- Borontribromide-mediated C-C bond formation in cyclic ketones: A transition metal free approach
-
Borontribromide (BBr3) is a well-known demethylating agent. The current investigation was focused on a new application of borontribromide as a C-C bond forming agent in cyclic ketones. In this study, borontribromide mediated C-C bond formation reactions of tetralones, chromenone, thiochromenone and indanones were explored. A methoxy group containing ketones showed selective C-C bond formation reaction instead of demethylation of the methoxy group. MM2 steric energy calculations for the final products showed that the reaction favored the formation of exo- or endo-cyclic double bond containing products, depending upon their low MM2 steric energy in a specific frame structure, as observed in X-ray crystallography. A comprehensive crystallographic and pi-stacking analysis of product 10a demonstrated the formation of 10a as an enantiomeric mixture, and its centre of inversion was stabilized by a set of three unique pi-pi interactions.
- Ahmad, Imran,Pathak, Vinay,Vasudev, Prema G.,Maurya, Hardesh K.,Gupta, Atul
-
p. 24619 - 24634
(2014/07/07)
-
- Sustainable flow oppenauer oxidation of secondary benzylic alcohols with a heterogeneous zirconia catalyst
-
A flow chemistry process for the Oppenauer oxidation of benzylic secondary alcohols using partially hydrated zirconium oxide and a simple carbonyl containing oxidant such as acetone, cyclohexanone, and neopentanal is reported. The heterogeneous oxidative system could be applied to a wide range of functionalized alcohol substrates, allowing clean and fast delivery of ketone products within a few minutes between 40 and 100 C.
- Chorghade, Rajeev,Battilocchio, Claudio,Hawkins, Joel M.,Ley, Steven V.
-
supporting information
p. 5698 - 5701
(2013/12/04)
-
- Synthesis and evaluation of dimeric 1,2,3,4-Tetrahydro-naphthalenylamine and Indan-1-ylamine derivatives with mast cell-stabilising and anti-allergic activity
-
In a continuation of our studies into 4-Amino-3,4-dihydro-2H-naphthalen-1-ones as novel modulators of allergic and inflammatory phenomena, we have extended our work to include dimeric analogues. Of these derivatives, the most promising activity was seen with tertiary amine 58a, which exhibited potent mast cell-stabilising activity in vitro against a variety of stimuli and also in vivo against passive cutaneous anaphylaxis.
- Barlow, James W.,Walsh, John J.
-
scheme or table
p. 25 - 37
(2010/03/04)
-
- Solvent-free friedel-crafts cyclization with trichloroacetic anhydride
-
Friedel-Crafts cyclization products were obtained using 1.1 equivalents of environmentally benign trichloroacetic anhydride as sole reagent and solvent. The resulting ketones included benzothiepins, benzothiopyrans, benzoxepins, dibenzothiepins, dibenzoxepins, and tetralones.
- Andrews, Ben,Bullock, Kae,Condon, Shannon,Corona, John,Davis, Roman,Grimes, John,Hazelwood, Andrew,Tabet, Elie
-
experimental part
p. 2664 - 2673
(2009/12/04)
-
- Cobalt-catalyzed oxidative kinetic resolution of secondary benzylic alcohols with molecular oxygen
-
The oxidative kinetic resolution of secondary alcohols using molecular oxygen and olefins was catalyzed by the optically active ketoiminatocobalt(II) complexes. The various secondary benzylic alcohols were subjected to the aerobic oxidative reaction to afford optically active alcohols of high ee along with the corresponding ketones in high yield. The oxidation of the deuterated alcohols revealed that the accompanying olefin mediated the oxidation for conversion to the corresponding α-deuterated ketones. Copyright
- Yamada, Tohru,Higano, Sho,Yano, Takanori,Yamashita, Yoshihiro
-
supporting information; experimental part
p. 40 - 41
(2009/12/03)
-
- Efficient synthesis of 1-tetralones from 4-arylbutyric acids by combined use of solid acid catalysts and microwave irradiation
-
Solid acid catalysts such as H-Beta zeolites effectively promote dehydrative intramolecular cyclization of 4-arylbutyric acids under microwave irradiation to give 1-tetralone derivatives in high yields. Copyright
- Hiroki, Kazuaki,Hatori, Makiko,Yamashita, Hiroshi,Sugiyama, Jun-Ichi
-
p. 320 - 321
(2008/09/20)
-
- In(III)-mediated chemoselective dehydrogenative interaction of ClMe 2SiH with carboxylic acids: Direct chemo- And regioselective friedel-crafts acylation of aromatic ethers
-
Chemoselective dehydrogenative interaction of ClMe2SiH with a carboxylic acid group in the presence of InX3 is reported. 13C NMR investigation revealed the formation of PhCOOSi(Cl)Me 2as the major transient intermediate. Chemo- and regioselective Friedel-Crafts acylation of aromatic ethers directly from carboxylic acids was established.
- Babu, Srinivasarao Arulananda,Yasuda, Makoto,Baba, Akio
-
p. 405 - 408
(2008/02/12)
-
- Benzylic oxidation catalyzed by dirhodium(II,III) caprolactamate
-
(Chemical Equation Presented) Dirhodium caprolactamate [Rh 2(cap)4] is an effective catalyst for benzylic oxidation with tert-butyl hydroperoxide (TBHP) under mild conditions. Sodium bicarbonate is the optimal base additive for substrate conversion. Benzylic carbonyl compounds are readily obtained, and a formal synthesis of palmarumycin CP 2 using this methodology is described.
- Catino, Arthur J.,Nichols, Jason M.,Choi, Hojae,Gottipamula, Sidhartha,Doyle, Michael P.
-
p. 5167 - 5170
(2007/10/03)
-
- Synthesis of 1-tetralone derivatives using a Stille cross coupling/friedel crafts acylation sequence
-
An efficient method of synthesis of 1-tetralones has been achieved featuring a Stille cross-coupling reaction as the key step.
- Vercouillie, Johnny,Abarbri, Mohamed,Parrain, Jean-Luc,Duchene, Alain,Thibonnet, Jerome
-
p. 3751 - 3762
(2007/10/03)
-
- Synthesis of Methoxy-2-hydroxy-1,4-naphthoquinones and Reaction of One Isomer with Aldehydes under Basic Conditions
-
Two protocols for the synthesis of methoxy-2-hydroxy-1,4-naphthoquinones were investigated in order to evaluate their behavior towards aldehydes under amine-basic conditions. Both the nature of the quinone and aliphatic aldehyde contribute to the viability of this condensation as well as further transformations.
- Ameer, Farouk,Giles, Robin G. F.,Green, Ivan R.,Pearce, Rene
-
p. 1247 - 1258
(2007/10/03)
-
- Synthesis of 1-tetralones by intramolecular Friedel-Crafts reaction of 4-arylbutyric acids using Lewis acid catalysts
-
Intramolecular Friedel-Crafts reaction of 4-arylbutyric acids efficiently proceeded in the presence of catalytic amounts of Lewis acids such as Bi(NTf2)3 and M(OTf)3 (M=Bi, Ga, In and rare-earth metals) to form 1-tetralones. Chroman-4-one and thiochroman-4-one were also obtained in good yields from 3-phenoxypropionic acid and 3-phenylthiopropionic acid, respectively.
- Cui, Dong-Mei,Kawamura, Masato,Shimada, Shigeru,Hayashi, Teruyuki,Tanaka, Masato
-
p. 4007 - 4010
(2007/10/03)
-
- Regiospecific synthesis of carboxylated and simple α-tetralones with homophthalates and various acrylates by a simple condensation method
-
Various carboxylated enols (3) have been prepared by taking advantage of simple condensation reactions of various homophthalates (1) with different acrylates (2), and these enols under heating with two different solvents (DMF and DMSO), afforded ten specific α-tetralones in good to moderate yields using NaCl as a catalyst.
- Roy,Rahman,Islam
-
p. 594 - 596
(2007/10/03)
-
- Epoxidation of 8a-alkyl-1,2,3,4,6,8a-hexahydronaphthalen-1-ones and -1-ols
-
The regio- and diastereoselectivities of the epoxidations of decalin-1,4-dienones and dienols obtained from the Birch reductive alkylation of different α-tetralones is described. They appear to depend on the steric approach control of the peroxide and show an important contribution to the directing effect of homoallylic alcohols.
- Labadie,Cravero,Gonzalez-Sierra
-
p. 708 - 712
(2007/10/03)
-
- PYRIMIDINE DERIVATIVES
-
The disclosed pyrimidine derivatives, and pharmaceutically acceptable salts thereof, exhibit useful pharmacological properties, in particular use as 5HT 2C-antagonists. The invention is also directed to formulations and methods for treatment.
- -
-
-
- Heterogeneous Permanganate Oxidations. 7. the Oxidation of Aliphatic Side Chains
-
Alkylbenzene side chains are oxidized at the benzylic position when treated under heterogeneous conditions with permanganate adsorbed on a solid support. The products are alcohols if the benzylic carbon is tertiary, or ketones if it is secondary. Carbon-carbon bond cleavage, which usually occurs when these same compounds are oxidized by permanganate under homogeneous conditions, does not occur. A unique selectivity is observed for the oxidation of derivatives of indane, 1, and tetralin, 2, in which one of the methylenes is replaced by an oxygen. If the oxygen is in the α-position, no reaction occurs; if it is in the β-position, good yields of the corresponding lactone are obtained. A mechanism consistent with the observed selectivity has been proposed.
- Noureldin, Nazih A.,Zhao, Dongyuan,Lee, Donald G.
-
p. 8767 - 8772
(2007/10/03)
-
- An unusual C-C bond cleavage with chromium VI reagents: Oxidation of primary alcohols to ketones
-
Oxidation of 1-hydroxymethylindanes and 1-hydroxymethyltetralins with PDC or PCC in methylene chloride affords 1-indanones and 1-tetralones.
- Bijoy,Subba Rao
-
p. 2701 - 2708
(2007/10/02)
-
- 1,3-Benzodithiolium Cation Mediated Cyclization Reactions
-
General protocols for the construction of various ring systems employing cation olefin cyclizations initiated by the readily accessible 1,3-benzodithiolium ion are described.Several substituted tetralones and tetralins can be rapidly assembled by this methodology as can a variety of substituted bicyclooctane and tricyclic ring systems.The products of these transformations are amenable to interconversion into a range of functionalized species.
- Rigby, James H.,Kotnis, Atul,Kramer, James
-
p. 5078 - 5088
(2007/10/02)
-
- Structure Elucidation and Total Synthesis of New Tanshinones Isolated from Salvia miltiorrhiza Bunge (Danshen)
-
Totally 11 new compounds have been isolated from the dried root of Salvia miltiorrhiza Bunge "Danshen" and their structures were elucidated by means of spectrometric methods.The total syntheses of two new compounds, namely, 1,2-didehydromiltirone and 4-methylenemiltirone, are also reported.
- Chang, Hson Mou,Cheng, Kwok Ping,Choang, Tai Francis,Chow, Hak Fun,Chui, Kuk Ying,et al.
-
p. 3537 - 3543
(2007/10/02)
-
- BIMETALLIC OXIDATION CATALYSTS: OXIDATIONS WITH TERT.BUTYLHYDROPEROXIDE MEDIATED BY BIS-(TRIBUTYLTIN OXIDE) DIOXOCHROMIUM (VI)
-
At 40-80 deg C, t.BuOOH in conjunction with catalytic amounts of (n.Bu3SnO)2CrO2 1 oxidizes benzylic alcohols, methylenes in α-position of aryl, ethylenic or acetylenic groups into ketones, anthracene into anthraquinone, adamantane into adamantan-1-ol and 2-one.Except for propargylic oxidations, yields are generally superior to those obtained when CrO3 is used as catalyst instead of 1.
- Muzart, Jacques
-
p. 2061 - 2068
(2007/10/02)
-
- PRACTICAL CHROMIUMVI OXIDE-CATALYZED BENZYLIC OXIDATIONS USING 70percent TERT-BUTYLHYDROPEROXIDE
-
In using 70percent t.BuOOH and catalytic amounts of chromic anhydride, benzylic methylene groups are oxidized at room temperature to carbonyl functions in fair yields.
- Muzart, Jacques
-
p. 2131 - 2132
(2007/10/02)
-
- CHROMIUMVI COMPLEX CATALYZED BENZYLIC OXIDATIONS IN THE PRESENCE OF TERT.BUTYL HYDROPEROXIDE
-
In using t.BuOOH and a small quantity of 2,4-dimethylpentane-2,4-diol cyclic chromate, benzylic methylene groups are oxidised into carbonyl functions; t.butylperoxy compounds are postulated as intermediates.
- Muzart, Jacques
-
p. 3139 - 3142
(2007/10/02)
-
- An approach to the biomimetic synthesis of aryltetralin lignans
-
The BF3 catalysed cyclisation of 3-arylpropyl substituted quinone-methide ketals affords a mild, biomimetic route to aryltetralins. 1H- and 13C-NMR spectra of the products are reported.
- Pelter, Andrew,Ward, Robert S.,Rao, Ramohan R.
-
p. 2933 - 2938
(2007/10/02)
-
- Methoxybenzopyrene 4,5-Oxides Labeled with Carbon-13: Electronic Effects in the NIH Shift
-
The synthesis of 9-methoxy-4,5-dihydrobenzopyrene-4-13C4,5-oxide and -5-13C4,5-oxide and of 8-methoxy-4,5-dihydrobenzopyrene-4-13C4,5-oxide is reported.The compounds were synthesized in yields of 15percent each from unlabeled precursors. 13C NMR analysis of the conversion of the 4,5-oxides to 4-phenols and 5-phenols (NIH shift) revealed a very strong electronic effect of a 9-methoxy substituent, which gave only the 4-phenol, and a significant but weaker effect of an 8-methoxy substituent, which gave both phenols with the 5-phenol predominating.
- Silverman, I. Robert,Daub, Guido H.,Jagt, David L. Vander
-
p. 5550 - 5556
(2007/10/02)
-
- 1,3-BENZODITHIOLIUM ION MEDIATED ANNULATIONS
-
A mild and selective method for cyclizations onto aromatic systems using 1,3-benzodithiolium ions is described.
- Rigby, James H.,Kotnis, Atul,Kramer, James
-
p. 2939 - 2940
(2007/10/02)
-
- 3-NITROCYCLOALKENONES, SYNTHESIS AND USE AS REVERSE AFFINITY CYCLOALKYNONE EQUIVALENTS
-
A partical synthesis of 3-nitrocycloalkenones and their utilization as dienophiles in the Diels-Alder reaction are discribed.The results demonstrate a reverse affinity equivalency between these β-nitro-enones and "cycloalkynones".
- Corey, E. J.,Estreicher, Herbert
-
p. 603 - 606
(2007/10/02)
-
- ACYL AZIDES AS ACYLATING AGENTS. A FACILE SYNTHESIS OF SUBSTITUTED TETRALONES
-
Treatment of 4-aryl butyryl azides or the intermediate mixed carbonic anhydrides with excess polyphosphoric acid or aluminium trichloride, respectively, provide a versatile method of synthesis of substituted tetralones, applicable to those cases where the necessary acid chlorides are unstable or difficult to prepare.
- Sanchez, I. H.,Mendoza, M. T.,Aguilar, M. A.,Martell, A. E.,Gonzalez, M. E.,Lemini, C.
-
p. 1501 - 1502
(2007/10/02)
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- Synthesis and antiallergic activity of 2 hydroxy 3 nitro 1,4 naphthoquinones
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A selection of novel 2-hydroxy-3-nitro-1,4-naphthoquinones are shown to be potent inhibitors of rat passive cutaneous anaphylaxis (PCA) and to have highest potency with alkyl substitution at both C-6 and C-7. The most potent compounds were 7c and 7e which produced a 50% inhibition in the rat PCA test at doses of about 10 μM/kg following subcutaneous administration and showed activity after oral administration. Related 4-hydroxy-3-nitro-2(1H)-naphthalenones had no effect on rat PCA in doses up to 500 μM/kg.
- Buckle,Cantello,Smith,Spicer
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p. 1059 - 1064
(2007/10/06)
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