RESUMEN
An efficient primary-amine-directed, palladium-catalyzed C-H halogenation (X=I, Br, Cl) of phenylalanine derivatives is reported on a range of quaternary amino acid (AA) derivatives thanks to suitable conditions employing trifluoroacetic acid as additive. The extension of this original native functionality-directed ortho-selective halogenation was even demonstrated with the more challenging native phenylalanine as tertiary AA.
Asunto(s)
Aminas , Paladio , Catálisis , Halogenación , FenilalaninaRESUMEN
Invited for the cover of this issue are Jean-François Brière, Cédric Schneider, Guillaume Journot and co-workers from the COBRA laboratory and Oril Industrie (Normandy, France). The image shows the progression from questioning how to easily and regioselectively introduce halogen atoms to amino acids to the discovery of a catalytic functional-group-directed C-H halogenation of phenylalanine derivatives. Read the full text of the article at 10.1002/chem.202102411.
Asunto(s)
Aminas , Paladio , Catálisis , Halogenación , Humanos , FenilalaninaRESUMEN
A regioselective Pd-catalyzed domino carbopalladation/decarboxylative allylic alkynylation of ortho-iodoallenamides with alkynyl carboxylic acids was studied. This domino process, based on the consecutive formation of C(sp2)-C(sp2) and C(sp3)-C(sp) bonds, was originally achieved for the design of a novel library of prop-2-ynyl isoquinolinones and then extended to indoles. Finally, a general three-step one-pot strategy involving in situ generation of allenamide, π-allyl-Pd complex formation, and decarboxylative allylic alkynylation was subsequently set up.
RESUMEN
Herein, palladium-catalyzed Miyaura borylation of 4-bromo-2,4'-bithiazoles followed by Suzuki-Miyaura cross-coupling reaction (named the MBSC process) with (hetero)aryl- and alkenyl halides is reported. This methodology offers rapid access to various 2',4-disubstituted 2,4'-bithiazole features including naturally-occurring 4-alkenylated and 4-pyridinylated 2,4'-bithiazoles. To prove its application, a concise approach for the synthesis of a heterocyclic cluster of the thiopeptide d-series antibiotic GE2270 is reported through a late-stage MBSC strategy.
Asunto(s)
Hidrocarburos Halogenados/química , Tiazoles/síntesis química , Catálisis , Técnicas de Química Sintética/métodos , Paladio/química , Péptidos Cíclicos/química , Estereoisomerismo , Tiazoles/químicaRESUMEN
The construction and subsequent orthogonal functionalization of a hitherto unknown oxazolo[5',4':4,5]pyrano[2,3-b]pyridine are reported. A palladium-catalyzed direct C-H bond functionalization methodology was used to build the tricyclic scaffold as well as to achieve the subsequent C-H bond functionalization at the C-2 position of the oxazole unit with various (hetero)aryl iodides. Remarkably, selective C-H construction and functionalization procedures preserve the chorine atom on the pyridine moiety offering a late-stage substitution site to progress drug design.
RESUMEN
Copper-catalyzed direct C-H fluoroalkenylation of heterocycles using various gem-bromofluoroalkenes as electrophiles is reported. This efficient method offers step-economical, low-cost and stereocontrolled access to relevant heteroarylated monofluoroalkenes. The synthesis of fluorinated analogues of biomolecules and therapeutic agents for the treatment of Duchenne muscular dystrophy as application is reported.
Asunto(s)
Alquenos/química , Cobre/química , Compuestos Heterocíclicos/química , Hidrocarburos Fluorados/síntesis química , Catálisis , Hidrocarburos Fluorados/química , Estructura MolecularRESUMEN
A straightforward method for direct decarboxylative arylation of 1- and 3-carboxy isoquinaldic acid N-oxides with aryl iodides is reported. The reaction proceeded selectively at the carboxy function site to exclusively give the corresponding C-1 or C-3 arylated product. This methodology tolerates various aryl iodides substituted by electronically different groups. Combined with subsequent Reissert-Henze chlorination and SNAr amination, the decarboxylative arylation provides an efficient access to 1,3-functionalized isoquinoline-based antitumor agent.
Asunto(s)
Óxidos N-Cíclicos/química , Isoquinolinas/síntesis química , Halogenación , Yoduros/química , Isoquinolinas/química , Estructura MolecularRESUMEN
Pd/Cu-catalyzed decarboxylative/direct C-H alkenylations of heteroarenes with α-fluoroacrylic acid is reported. This method offers step-economical and stereocontrolled access to valuable heteroarylated monofluoroalkenes as both Z and E isomers, which are known to be useful in the synthesis of fluorinated biomolecules.
RESUMEN
Decarboxylative cross-coupling reactions of substituted 2-carboxyazine N-oxides, with a variety of (hetero)aryl halides, by bimetallic Pd(0)/Cu(I) and Pd(0)/Ag(I) catalysis are reported. Two possible pathways, a conventional bimetallic-catalyzed decarboxylative arylation, as well as a protodecarboxylative/direct C-H arylation sequence have been considered. These methods provide the first general decarboxylative arylation methodology for the 2-carboxyazine series.
RESUMEN
Strolling the ring: a general regioselective directed peri(C4)-metalation route to 1 through an in situ N-anionic protection of C2 is reported. The azaindoles may be elaborated by directed ortho metalation (DoM) and Suzuki coupling to more complex heterocyclic systems. An iterative ring-walk DoM sequence furnishes the exhaustively substituted 2. DMG=directed metalation group, TMEDA=N,N,N',N'-tetramethylethylenediamine, TMS=trimethylsilyl.
RESUMEN
Herein, we present a regioselective Pd-catalyzed C-H [4 + 2] benzannulation of N-unprotected 3-arylindoles with external readily available 1,3-dienes via an original sequence involving a Pd-catalyzed domino carbopalladation of 1,3-dienes/direct C2-H allylation of an indole ring followed by an oxidation or reduction step. Depending on the nature of the solvent, DCE or CH3CN, two consecutive approaches, oxidative or reductive, have been validated and applied to the design of a novel library of C6-alkyl or (E)-C6-styryl-benzo[c]carbazoles in moderate to good yields.
Asunto(s)
Carbazoles , Paladio , Estructura Molecular , Polienos , Oxidación-ReducciónRESUMEN
BACKGROUND: Vascular anomalies comprise a diverse group of rare diseases with altered blood flow and are often associated with coagulation disorders. The most common example is a localized intravascular coagulopathy in venous malformations leading to elevated D-dimers. In severe cases, this may progress to a disseminated intravascular coagulopathy with subsequent consumption of fibrinogen and thrombocytes predisposing to serious bleeding. A separate coagulopathy is the Kasabach-Merritt phenomenon in kaposiform hemangioendothelioma characterized by platelet trapping leading to thrombocytopenia and eventually consumptive coagulopathy. Our previous work showed impaired von Willebrand factor and platelet aggregometry due to abnormal blood flow, i.e., in ventricular assist devices or extracorporeal membrane oxygenation. With altered blood flow also present in vascular anomalies, we hypothesized that, in particular, the von Willebrand factor parameters and the platelet function may be similarly impacted. METHODS: We prospectively recruited 73 patients with different vascular anomaly entities and analyzed their coagulation parameters. RESULTS: Acquired von Willebrand syndrome was observed in both of our patients with Kasabach-Merritt phenomenon. In six out of nine patients with complex lymphatic anomalies, both the vWF antigen and activity were upregulated. Platelet aggregometry was impaired in both patients with Kasabach-Merritt phenomenon and in seven out of eight patients with an arteriovenous malformation. CONCLUSIONS: The analysis of coagulation parameters in our patients with vascular anomalies advanced our understanding of the underlying pathophysiologies of the observed coagulopathies. This may lead to new treatment options for the, in part, life-threatening bleeding risks in these patients in the future.
Asunto(s)
Trastornos de la Coagulación Sanguínea , Coagulación Sanguínea , Malformaciones Vasculares , Humanos , Plaquetas , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/fisiopatología , Hemangioendotelioma/etiología , Hemangioendotelioma/fisiopatología , Síndrome de Kasabach-Merritt/etiología , Síndrome de Kasabach-Merritt/fisiopatología , Factor de von Willebrand/metabolismo , Malformaciones Vasculares/complicaciones , Malformaciones Vasculares/fisiopatología , Trastornos de la Coagulación Sanguínea/etiología , Trastornos de la Coagulación Sanguínea/fisiopatologíaRESUMEN
The Anaplastic Lymphoma Kinase (ALK) is a therapeutic target for personalized medicine in selected cancers. Despite excellent clinical responses to ALK inhibitors, most patients develop drug resistance and relapse. New compounds with alternative binding modes are needed to overcome resistant mutants. Here we describe a medicinal chemistry effort to the design and development of novel ALK inhibitors based on a 4,6-substituted α-carboline scaffold. Active compounds were able to inhibit the gatekeeper L1196M mutant, in several cases better than the wild-type enzyme. Compound 43 showed potent non-ATP-competitive inhibition of wild-type and mutant ALK, including G1202R, in biochemical and cellular assays, as well as in xenograft mouse models.
Asunto(s)
Carbolinas , Proteínas Tirosina Quinasas Receptoras , Quinasa de Linfoma Anaplásico , Animales , Carbolinas/farmacología , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Ratones , Mutación , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacologíaRESUMEN
[This corrects the article DOI: 10.1021/acsomega.2c00507.].
RESUMEN
Herein, we present a regioselective Cu-catalyzed oxidative allylic C(sp3)-H arylation by radical relay using a broad range of heteroaryl boronic acids with inexpensive and readily available unactivated terminal and internal olefins. This C(sp2)-C(sp3) allyl coupling has the advantage of using cheap, abundant, and nontoxic Cu2O without the need to use prefunctionalized alkenes, thus offering an alternative method to allylic arylation reactions that employ more traditional coupling partners with preinstalled leaving groups (LGs) at the allylic position.
RESUMEN
Pyrazolo[1,5-a]-1,3,5-triazine myoseverin derivatives 1a-c were prepared from 4-(N-methyl-N-phenylamino)-2-methylsulfanylpyrazolo[1,5-a]-1,3,5-triazine 2. Their cytotoxic activity, inhibition of tubulin polymerization, and cell cycle effects were evaluated. Compounds 1a and 1c are potent tubulin inhibitors and displayed specific antiproliferative activity in colorectal cancer cell lines at micromolar concentrations.
Asunto(s)
Purinas/síntesis química , Purinas/farmacología , Pirazoles/síntesis química , Pirazoles/farmacología , Triazinas/síntesis química , Triazinas/farmacología , Moduladores de Tubulina/síntesis química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Humanos , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Moduladores de Tubulina/metabolismo , Moduladores de Tubulina/farmacologíaRESUMEN
Palladium-catalyzed intramolecular carbopalladation onto allenamides completed by direct C-H allylation of heterocycles is studied. The domino construction/heteroarylation of isoquinolone process is first achieved. A general three-step one-pot strategy, involving in situ generation of allenamide, π-allyl-Pd complex generation, and interception with heteroarenes, has been subsequently set up. This methodology has been extended to the construction/heteroarylation of indoles, dihydroquinolines, isoquinolin(on)es, and medium-sized nitrogen heterocycles, which are known to be key challenging structural motifs with pharmaceutical significance.
RESUMEN
The natural restoration of soils polluted by aromatic hydrocarbons such as benzene, toluene, ethylbenzene and m- and p-xylene (BTEX) may be accelerated by inoculation of specific biodegraders (bioaugmentation). Bioaugmentation mainly involves introducing bacteria that deploy their metabolic properties and adaptation potential to survive and propagate in the contaminated environment by degrading the pollutant. In order to better understand the adaptive response of cells during a transition to contaminated material, we analyzed here the genome and short-term (1 h) changes in genome-wide gene expression of the BTEX-degrading bacterium Pseudomonas veronii 1YdBTEX2 in non-sterile soil and liquid medium, both in presence or absence of toluene. We obtained a gapless genome sequence of P. veronii 1YdBTEX2 covering three individual replicons with a total size of 8 Mb, two of which are largely unrelated to current known bacterial replicons. One-hour exposure to toluene, both in soil and liquid, triggered massive transcription (up to 208-fold induction) of multiple gene clusters, such as toluene degradation pathway(s), chemotaxis and toluene efflux pumps. This clearly underlines their key role in the adaptive response to toluene. In comparison to liquid medium, cells in soil drastically changed expression of genes involved in membrane functioning (e.g., lipid composition, lipid metabolism, cell fatty acid synthesis), osmotic stress response (e.g., polyamine or trehalose synthesis, uptake of potassium) and putrescine metabolism, highlighting the immediate response mechanisms of P. veronii 1YdBTEX2 for successful establishment in polluted soil.