RÉSUMÉ
Hydrogen sulfide (H2 S) is an important endogenous gasotransmitter, but the targeted delivery and real-time feedback of exogenous H2 S are still challenging. With the aid of density functional theory (DFT) calculations, we designed a new 1,3-dithiolium-4-olate (DTO) compound, which can react with a strained alkyne via the 1,3-dipolar cycloaddition and the retro-Diels-Alder reaction to generate carbonyl sulfide (COS) as the precursor of H2 S, and a thiophene derivative with turn-on fluorescence. Moreover, the diphenylamino substituent in DTO greatly increases the mitochondrial targeting of this H2 S delivery system. Such a bioorthogonal click-and-release reaction has integrated three functions in one system for the first time: (1)â in situ controllable H2 S release, (2)â concomitant fluorescence response, and (3)â mitochondria-targeted delivery. In addition, we investigated the mitochondrial membrane potential loss alleviation by using this system in H9c2 cells under oxidative stress.
Sujet(s)
Développement de médicament , Sulfure d'hydrogène/métabolisme , Mitochondries/métabolisme , Toluène/analogues et dérivés , Théorie de la fonctionnelle de la densité , Humains , Sulfure d'hydrogène/composition chimique , Mitochondries/composition chimique , Structure moléculaire , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/métabolismeRÉSUMÉ
A series of novel substituted phenyl 1, 3-thiazolidin-4-one sulfonyl derivatives 5 (a-t) were synthesized and screened for their in-vitro anti-microbial and anti-viral activity. The result of the anti-microbial assay demonstrated compounds 5d, 5f, 5g, 5h, 5i, 5j showed prominent inhibitory activity against all the tested Gram-positive and Gram-negative bacterial strains, while compounds 5g, 5j, 5o, 5p, 5q showed significant activity against the entire set of fungal strains as compared to standard drug Ampicillin and Clotrimazole, respectively. The antimicrobial study revealed that compounds having electron-withdrawing groups showed significant antimicrobial potency. The most active antibacterial compound 5j showed potent inhibition of S. aureus DNA Gyrase enzyme as a possible mechanism of action for antimicrobial activity. Moreover, the antiviral testing of selected compounds showed considerable activity against Herpes simplex virus-1(KOS), Herpes simplex virus-2 (G), Herpes simplex virus-1(TK- KOS ACVr), Vaccinia virus, Human Coronavirus (229E), Reovirus-1, Sindbis virus, Coxsackie virus B4, Yellow Fever virus and Influenza A, B virus. Compounds 5h exhibited low anti-viral activity against HIV-1(strain IIIB) and HIV-2 (strain ROD). The study clearly outlined that synthesized compounds endowed with good antimicrobial property together with considerable antiviral activity.
Sujet(s)
Phénols/synthèse chimique , Sulfonamides/synthèse chimique , Toluène/analogues et dérivés , Animaux , Antibactériens/synthèse chimique , Antibactériens/composition chimique , Antibactériens/pharmacologie , Antiviraux/synthèse chimique , Antiviraux/composition chimique , Antiviraux/pharmacologie , Bactéries/classification , Bactéries/effets des médicaments et des substances chimiques , Lignée cellulaire , Chlorocebus aethiops , Humains , Phénols/composition chimique , Phénols/pharmacologie , Sulfonamides/composition chimique , Sulfonamides/pharmacologie , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/pharmacologie , Cellules Vero , Virus/classification , Virus/effets des médicaments et des substances chimiquesRÉSUMÉ
To find potential inhibitors of human carbonic anhydrase IX (CAIX), we have successfully deigned, synthesized and characterized three p-toluene sulphonylhydrazone derivatives (1-3). Molecular docking studies provided the structural basis of CAIX inhibition and a deeper insight into the protein-ligand interactions. p-Toluene sulphonylhydrazone derivatives show a well organized conformational compatibility with the active site of CAIX. The protein-ligand complex was stabilized by several non-covalent interactions offered by residues present in the active site cavity. The actual binding affinity of synthesized compounds with CAIX was experimentally measured by fluorescence and isothermal titration calorimetry (ITC). Results of both fluorescence binding and ITC measurements show the binding affinity of p-Toluene sulphonylhydrazone derivatives to the CAIX in the µM range. CAIX enzyme inhibition assay showed the IC50 values in nM range. Though all the three compounds (1-3) showed a good binding with CAIX, compound 2 showed the best inhibition of CAIX activity. These compounds were non-toxic on normal cell lines (HEK-293) and significantly inhibit the proliferation of hypoxic cancer cells. All compounds induce apoptosis in the hypoxic cancer cells. These compounds may be further exploited as promising therapeutic agents to control the hypoxia-induced tumors.
Sujet(s)
Carbonic anhydrase IX/antagonistes et inhibiteurs , Inhibiteurs de l'anhydrase carbonique/pharmacologie , Hydrazones/composition chimique , Tumeurs/traitement médicamenteux , Carbonic anhydrase IX/composition chimique , Inhibiteurs de l'anhydrase carbonique/synthèse chimique , Inhibiteurs de l'anhydrase carbonique/composition chimique , Hypoxie cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cellules HEK293 , Humains , Hydrazones/synthèse chimique , Hydrazones/pharmacologie , Simulation de docking moléculaire , Tumeurs/enzymologie , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/pharmacologie , Hypoxie tumorale/effets des médicaments et des substances chimiquesRÉSUMÉ
In the classic Diels-Alder [4 + 2] cycloaddition reaction, the overall degree of unsaturation (or oxidation state) of the 4π (diene) and 2π (dienophile) pairs of reactants dictates the oxidation state of the newly formed six-membered carbocycle. For example, in the classic Diels-Alder reaction, butadiene and ethylene combine to produce cyclohexene. More recent developments include variants in which the number of hydrogen atoms in the reactant pair and in the resulting product is reduced by, for example, four in the tetradehydro-Diels-Alder (TDDA) and by six in the hexadehydro-Diels-Alder (HDDA) reactions. Any oxidation state higher than tetradehydro (that is, lacking more than four hydrogens) leads to the production of a reactive intermediate that is more highly oxidized than benzene. This increases the power of the overall process substantially, because trapping of the reactive intermediate can be used to increase the structural complexity of the final product in a controllable and versatile manner. Here we report an unprecedented overall 4π + 2π cycloaddition reaction that generates a different, highly reactive intermediate known as an α,3-dehydrotoluene. This species is in the same oxidation state as a benzyne. Like benzynes, α,3-dehydrotoluenes can be captured by various trapping agents to produce structurally diverse products that are complementary to those arising from the HDDA process. We call this new cycloisomerization process a pentadehydro-Diels-Alder (PDDA) reaction-a nomenclature chosen for chemical taxonomic reasons rather than mechanistic ones. In addition to alkynes, nitriles (RC≡N), although non-participants in aza-HDDA reactions, readily function as the 2π component in PDDA cyclizations to produce, via trapping of the α,3-(5-aza)dehydrotoluene intermediates, pyridine-containing products.
Sujet(s)
Réaction de cycloaddition , Hydrogène/composition chimique , Toluène/analogues et dérivés , Benzène/composition chimique , Cyclisation , Diynes/composition chimique , Hydrogénation , Isomérie , Nitriles/composition chimique , Oxydoréduction , Pyridines/composition chimique , Terminologie comme sujet , Toluène/synthèse chimique , Toluène/composition chimiqueRÉSUMÉ
The practical synthesis of the C-ring precursor of paclitaxel starting from 3-methoxytoluene is described. Lipase-catalyzed kinetic resolution of a substituted cyclohexane-1,2-diol, derived from 3-methoxytoluene in three steps, successfully afforded a desired enantiomer with >99% ee, which was transformed to a cyclohexenone. 1,4-Addition of a vinyl metal species, followed by Mukaiyama aldol reaction with formalin in the presence of a Lewis acid provided the known C-ring precursor of paclitaxel in a 10 g scale.
Sujet(s)
Antinéoplasiques d'origine végétale/synthèse chimique , Paclitaxel/synthèse chimique , Toluène/analogues et dérivés , Toluène/synthèse chimique , Cyclohexanes/composition chimique , Formaldéhyde/composition chimique , Triacylglycerol lipase/composition chimiqueRÉSUMÉ
Drug therapy of seizures involves producing high levels of antiepileptic drugs in the blood. Drug must enter the brain by crossing from the blood into the brain tissue, called a transvascular route (TVR). Even before the drug can reach the brain tissue, factors such as systemic toxicity, macrophage phagocytises and reduction in oxygen content limit the success of this TVR. Encapsulating the drug within a nano scale delivering system, synthesising drugs with low molecular weight are the best mechanisms to deliver the drug to the brain. But through this article, we have explored a possibility of attaching a molecule 4-(trifluoromethyl) benzoic acid (TFMBA), that possess more number of fluorine atom, to benzodiazepine (BDZ) resulting in an ionic salt (S)-(+)-2,3-dihydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine5,11(10H,11aH)-dione with 4-(trifluoromethyl)benzoic acid. By this way, reducing the toxicity of BDZ than the conventional anti-epileptic drugs (AEDs), increasing the solubility, reducing the melting point, enriching the TVR with excess oxygen content with the support of fluorine. With all these important prerequisites fulfilled, the drug along with the attached molecule is expected to travel more comfortably through the TVR without any external support than any other conventional AEDs. FTIR, (1)H NMR, (13)C NMR, HRMS spectroscopy, HRTEM and In vitro cytotoxicity analysis supports this study.
Sujet(s)
Anticonvulsivants/composition chimique , Benzodiazépinones/composition chimique , Pyrroles/composition chimique , Toluène/analogues et dérivés , Anticonvulsivants/synthèse chimique , Anticonvulsivants/métabolisme , Anticonvulsivants/toxicité , Benzodiazépinones/synthèse chimique , Benzodiazépinones/toxicité , Carbamazépine/toxicité , Fructose/analogues et dérivés , Fructose/toxicité , Halogénation , Humains , Cellules MCF-7 , Masse moléculaire , Pyrroles/synthèse chimique , Pyrroles/toxicité , Solubilité , Stéréoisomérie , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/toxicité , Topiramate , Température de transitionRÉSUMÉ
Reaction of p-toluenesulfonyl chloride with amino acids gave sulfonamides p-T1a-k which upon amidation afforded p-T2a-k. Similarly, treatment involving α-toluenesulfonyl chloride and amino acids afforded the sulfonamides α-T1a-k. These two classes of sulfonamides were synthetically modified at their COOH end position to achieve N,N-diethylamido substituted p-toluenesulfonamides p-T2a-k and α-toluenesulfonamides α-T2a-k, respectively. The chemical structures of the compounds were validated with IR, Mass spectra, NMR as well as elemental analytical data. Both classes of compounds were screened against Escherichia coli and Staphylococcus aureus and their activity werecompared. It was remarkable to note that the α-toluene sulfonamides α-T2a-k were more active than their p-toluenesulfonamide counterparts p-T2a-k. Compound 1-(benzylsulfonyl)-N,N-diethylpyrrolidine-2-carboxamide α-T2a was the most potent antibacterial compound on S. aureus with MIC value of 3.12 µg mL(-1) while N,N-Diethyl-3-phenyl-2-(phenylmethylsulfonamide) propanamide α-T2j emerged as the best antibacterial motif against E. coli with MIC value of 12.5 µg mL(-1). Hence, these compounds especially the α-toluenesulfonamide core structural templates are good candidates for further study for future drug discovery.
Sujet(s)
Antibactériens/pharmacologie , Escherichia coli/effets des médicaments et des substances chimiques , Staphylococcus aureus/effets des médicaments et des substances chimiques , Sulfonamides/pharmacologie , Toluène/analogues et dérivés , Antibactériens/synthèse chimique , Découverte de médicament , Escherichia coli/croissance et développement , Spectroscopie par résonance magnétique , Spectrométrie de masse , Tests de sensibilité microbienne , Structure moléculaire , Spectrophotométrie IR , Staphylococcus aureus/croissance et développement , Relation structure-activité , Sulfonamides/synthèse chimique , Toluène/synthèse chimique , Toluène/pharmacologieRÉSUMÉ
We report the first example of the highly enantioselective synthesis of structurally diverse chiral dithioketals via asymmetric sulfenylation of various types of S-based nucleophiles, catalyzed by a cheap cinchona alkaloid derivative, dihydroquinine.
Sujet(s)
Quinidine/analogues et dérivés , Acides sulfiniques/composition chimique , Toluène/analogues et dérivés , Catalyse , Structure moléculaire , Quinidine/composition chimique , Toluène/synthèse chimique , Toluène/composition chimiqueRÉSUMÉ
The current pharmacological Chagas disease treatments, using Nifurtimox or Benznidazole, show limited therapeutic results and are associated with potential side effects, like mutagenicity. Using random screening we have identified new chemotypes that were able to inhibit relevant targets of the Trypanosoma cruzi. We found 3H-[1,2]dithioles with the ability to inhibit Trypanosoma cruzi triosephosphate isomerase (TcTIM). Herein, we studied the structural modifications of this chemotype to analyze the influence of volume, lipophilicity and electronic properties in the anti-T. cruzi activity. Their selectivity to parasites vs. mammalian cells was also examined. To get insights into a possible mechanism of action, the inhibition of the enzymatic activity of TcTIM and cruzipain, using the isolated enzymes, and the inhibition of membrane sterol biosynthesis and excreted metabolites, using the whole parasite, were achieved. We found that this structural framework is interesting for the generation of innovative drugs for the treatment of Chagas disease.
Sujet(s)
Toluène/analogues et dérivés , Trypanocides/composition chimique , Trypanocides/pharmacologie , Trypanosoma cruzi/effets des médicaments et des substances chimiques , Animaux , Lignée cellulaire , Relation dose-effet des médicaments , Évaluation préclinique de médicament , Macrophages/effets des médicaments et des substances chimiques , Souris , Stérols/antagonistes et inhibiteurs , Stérols/biosynthèse , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/pharmacologie , Trypanocides/synthèse chimique , Trypanosoma cruzi/métabolismeRÉSUMÉ
The deprotection of a common precursor moiety in dithiolene chemistry was discovered to be fully reversible, which, besides being relevant for researchers working in very different fields with these non-innocent ligand systems, may even have an impact on CO2 housekeeping, as the deprotected ligand acts as an efficient trap.
Sujet(s)
Toluène/analogues et dérivés , Spectroscopie par résonance magnétique/méthodes , Toluène/synthèse chimique , Toluène/métabolismeRÉSUMÉ
Replacement reactions of toluene-3,4-dithiolatoarsenic(III) chloride with oxygen and sulphur donor ligands like benzoic acid, thiobenzoic acid, anhydrous sodium acetate, thioacetic acid, phenol, thiophenol, sodium salicylate and thio glycolic acid in 1:1 molar ratio as well as disodium oxalate in 2:1 molar ratio in refluxing anhydrous benzene yielded toluene-3,4-dithiolatoarsenic(III) mono oxo or thio carboxylic or phenolic derivatives of the general formula SC(6)H(3)(CH(3))SAsR {where R=OOCC(6)H(5), SOCC(6)H(5), OOCCH(3), SOCCH(3), OC(6)H(5), SC(6)H(5), OOCC(6)H(4)(OH), SCH(2)COOH} and SC(6)H(3)(CH(3))SAsOOC-COOAsS(CH(3))C(6)H(3)S. These synthesized derivatives are yellow, yellow-brown solids/ liquids and are soluble in common organic solvents like benzene, chloroform, dichloromethane, dimethyl formamide, dimethyl sulphoxide etc. These derivatives have been characterized by melting point determination, molecular weight determination, elemental analysis (C, H, S and As), spectral {UV, IR, NMR ((1)H and (13)C), ESI-Mass, SEM and powder X-ray diffraction} and thermal (TGA, DTA and DSC) studies. Some of these compounds have been screened for their antimicrobial activities using the disc diffusion method. These derivatives have shown good activity as antibacterial and antifungal agents on some selected bacterial and fungal strains, which increased on increasing the concentration. Chloroamphenicol and terbinafin were used as standards for the comparison.
Sujet(s)
Antibactériens/synthèse chimique , Antibactériens/pharmacologie , Composés de l'arsenic/composition chimique , Oxygène/composition chimique , Soufre/composition chimique , Température , Toluène/synthèse chimique , Toluène/pharmacologie , Antibactériens/composition chimique , Bactéries/effets des médicaments et des substances chimiques , Calorimétrie différentielle à balayage , Électrons , Champignons/effets des médicaments et des substances chimiques , Ligands , Spectroscopie par résonance magnétique , Tests de sensibilité microbienne , Microscopie électronique à balayage , Poudres , Spectrométrie de masse ESI , Spectrophotométrie IR , Thermogravimétrie , Toluène/composition chimique , Diffraction des rayons XRÉSUMÉ
Doubly radical: A novel entry to α,n-didehydrotoluene (DHT) diradicals is disclosed and proceeds through the photochemical activation of (chlorobenzyl)trimethylsilanes with chloride loss and elimination of the SiMe(3) (+) group. The products formed in solution are indicative of the intermediacy of the three isomers of the α,n-DHT.
Sujet(s)
Silanes/composition chimique , Toluène/analogues et dérivés , Toluène/synthèse chimique , Alcadiènes/composition chimique , Alcynes/composition chimique , Cyclisation , Processus photochimiques , Photochimie/méthodes , Toluène/composition chimiqueRÉSUMÉ
In this study, the molecular structure and spectroscopic properties of title compound were characterized by X-ray diffraction, FT-IR and UV-vis spectroscopies. These properties of title compound were also investigated from calculative point of view. The X-ray diffraction and FT-IR analyses reveal the existence of keto form in the solid state. UV-vis spectra were recorded in different organic solvents. The results show that title compound exists in both keto and enol forms in DMSO, EtOH but it exists in enol form in benzene. In addition, the title compound in DMSO showed new absorption band at 436 nm due to the high ionizing effect of this solvent. The geometry optimization of title compound in gas phase was performed using DFT method with B3LYP applying 6-311G(d,p) basis set. TD-DFT calculations starting from optimized geometry were carried out in gas phase to calculate excitation energies of title compound. The non-linear optical properties were computed with the same level of theory and title compound showed a good second order nonlinear optical property. In addition, thermodynamic properties were obtained in the range of 100-500 K.
Sujet(s)
Composés azoïques/composition chimique , Agents colorants/composition chimique , Cyclohexènes/composition chimique , Cyclohexènes/synthèse chimique , Toluène/analogues et dérivés , Composés azoïques/synthèse chimique , Agents colorants/synthèse chimique , Cristallographie aux rayons X , Isomérie , Modèles moléculaires , Théorie quantique , Analyse spectrale , Toluène/synthèse chimique , Toluène/composition chimiqueRÉSUMÉ
BF(3)·OEt(2)-catalyzed direct cyanation of indoles and pyrroles using a less toxic, bench-stable, and easily handled electrophilic cyanating agent N-cyano-N-phenyl-para-toluenesulfonamide (NCTS) affords 3-cyanoindoles and 2-cyanopyrroles in good yields with excellent regioselectivity. The substrate scope is broad with respect to indoles and pyrroles.
Sujet(s)
Indoles/synthèse chimique , Acides de Lewis/composition chimique , Nitriles/composition chimique , Nitriles/synthèse chimique , Pyrroles/synthèse chimique , Sulfonamides/composition chimique , Sulfonamides/synthèse chimique , Toluène/analogues et dérivés , Catalyse , Indoles/composition chimique , Structure moléculaire , Pyrroles/composition chimique , Stéréoisomérie , Toluène/synthèse chimique , Toluène/composition chimiqueRÉSUMÉ
Pd-catalyzed highly para-selective C-H arylation of monosubstituted arenes (including toluene) is developed for the first time using an F(+) reagent as a bystanding oxidant. This finding provides a new retrosynthetic disconnection for para-substituted biaryl synthesis via C-H/C-H cross-coupling.
Sujet(s)
Hydrocarbures aromatiques/synthèse chimique , Palladium/composition chimique , Catalyse , Techniques de chimie synthétique/méthodes , Hydrocarbures aromatiques/composition chimique , Oxydants/composition chimique , Toluène/synthèse chimique , Toluène/composition chimiqueRÉSUMÉ
Ponatinib (AP24534) was previously identified as a pan-BCR-ABL inhibitor that potently inhibits the T315I gatekeeper mutant, and has advanced into clinical development for the treatment of refractory or resistant CML. In this study, we explored a novel series of five and six membered monocycles as alternate hinge-binding templates to replace the 6,5-fused imidazopyridazine core of ponatinib. Like ponatinib, these monocycles are tethered to pendant toluanilides via an ethynyl linker. Several compounds in this series displayed excellent in vitro potency against both native BCR-ABL and the T315I mutant. Notably, a subset of inhibitors exhibited desirable PK and were orally active in a mouse model of T315I-driven CML.
Sujet(s)
Alcynes/synthèse chimique , Alcynes/pharmacologie , Dérivés de l'aniline/synthèse chimique , Protéines de fusion bcr-abl/antagonistes et inhibiteurs , Toluène/synthèse chimique , Administration par voie orale , Alcynes/composition chimique , Dérivés de l'aniline/composition chimique , Dérivés de l'aniline/pharmacologie , Animaux , Cyclisation , Modèles animaux de maladie humaine , Protéines de fusion bcr-abl/génétique , Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Souris , Modèles moléculaires , Structure moléculaire , Mutation , Rats , Relation structure-activité , Toluène/composition chimique , Toluène/pharmacologieRÉSUMÉ
Since activation of p53 in response to cytotoxic stress may have proapoptotic or protective effects depending on the nature of the injury, inhibitors of p53 may have therapeutic interest as modulators of chemotherapy toxicity or efficacy. In an attempt to identify novel p53 inhibitors, a quality collection of compounds structurally related to pifithrin-ß were designed and synthesized as potential inhibitors of p53. The biochemical and biological evaluations supported that compounds of the tetrahydrobenzothiazole series were inhibitors of the p53 transcriptional activity and were effective in enhancing paclitaxel-induced apoptosis. In contrast, in spite of the increased cytotoxic potency, selected compounds of the benzothiazole series were not able to modulate the transcriptional activity of p53, as indicated by lack of change of p21 expression. The therapeutic interest of the compounds of the former series in combination with taxanes was confirmed in a human tumor xenograft model.
Sujet(s)
Antinéoplasiques , Benzothiazoles/synthèse chimique , Benzothiazoles/pharmacologie , Tumeurs de l'ovaire/traitement médicamenteux , Toluène/analogues et dérivés , Protéine p53 suppresseur de tumeur/antagonistes et inhibiteurs , Animaux , Antinéoplasiques/synthèse chimique , Antinéoplasiques/composition chimique , Antinéoplasiques/pharmacologie , Benzothiazoles/composition chimique , Lignée cellulaire tumorale , Modèles animaux de maladie humaine , Femelle , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Concentration inhibitrice 50 , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/pharmacologie , Transplantation hétérologueRÉSUMÉ
A scalable synthesis of a potent renin inhibitor (1) is described. The absolute stereochemistry is set via an unprecedented diastereoselective Dieckmann cyclization directed by a remote chiral protecting group. This transformation enables preparation of chiral 1,3-[3.3.1]-diazabicyclononenes by desymmetrization of alkyl-esters, with selectivities ranging from 4 to 17:1.
Sujet(s)
Composés azoïques/synthèse chimique , Composés hétérocycliques bicycliques/synthèse chimique , Inhibiteurs de protéases/synthèse chimique , Inhibiteurs de protéases/pharmacologie , Rénine/antagonistes et inhibiteurs , Toluène/analogues et dérivés , Composés azoïques/composition chimique , Composés hétérocycliques bicycliques/composition chimique , Cristallographie aux rayons X , Cyclisation , Conformation moléculaire , Structure moléculaire , Inhibiteurs de protéases/composition chimique , Stéréoisomérie , Toluène/synthèse chimique , Toluène/composition chimique , Toluène/pharmacologieRÉSUMÉ
A total of eight CF(3)-substituted phenylacetic and mandelic acids are shown to undergo efficient photodecarboxylation (PDC; Phi = 0.37-0.74) in basic aqueous solution to give the corresponding trifluoromethyltoluenes or trifluoromethylbenzyl alcohols. The products are consistent with the almost exclusive formation of benzylic carbanions that subsequently react with water, with minor amounts (< or = 5%) of radical-derived products detected. Quenching studies indicate that the reaction likely proceeds from the singlet excited state. This work demonstrates that the CF(3) group greatly facilitates the excited state ionic PDC of phenylacetic acids.
Sujet(s)
Hydrocarbures fluorés/composition chimique , Acides mandéliques/composition chimique , Phénylacétates/composition chimique , Alcools benzyliques/synthèse chimique , Alcools benzyliques/composition chimique , Décarboxylation , Structure moléculaire , Photochimie , Théorie quantique , Stéréoisomérie , Toluène/analogues et dérivés , Toluène/synthèse chimique , Toluène/composition chimique , Rayons ultravioletsRÉSUMÉ
A new process is described for preparing very pure linear alkanethiols and linear alpha,omega-alkanedithiols using a sequential alkylation of the title compound, followed by a ring closure to quantitatively give the corresponding 3-methyl[1,3]thiazolo[3,2-a]-[3,1]benzimidazol-9-ium salt and the alkanethiol derivative under mild conditions. The alkanethiol and the heteroaromatic salt are easily separated by a simple extraction process. The intermediate thiazolium quaternary salts resulting from the first reaction step can be isolated in quantitative yields, affording an odourless protected form of the thiols.