RESUMEN
An aryne annulation strategy for the synthesis of fused carbazoles is developed using indolyl ß-ketonitrile in a cascade manner. The reaction sequence involves aryne-mediated [2 + 2] cycloaddition cleavage and intramolecular Michael addition, followed by oxidation under transition-metal-free reaction conditions. Subsequently, conversion of benzo[b]carbazole-6-carbonitrile to carbazole quinone is observed upon prolongation of the reaction time. Furthermore, these materials exhibit high quantum efficiency, which promotes the light-emitting diode applications.
RESUMEN
Quorum-sensing (QS) is a cell density-dependent signaling pathway regulated by gene expression for intra- and interspecies communication. We have targeted QS activity in Pseudomonas aeruginosa, an opportunistic human pathogen that causes disease in immunocompromised patients, with a set of probes containing a variety of functional groups, including photoreactive (diazirine) and affinity (alkyne) moieties, that were synthesized using a four-component Ugi reaction (Ugi-4CR).
Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Humanos , Proteínas Bacterianas/metabolismo , Infecciones por Pseudomonas/tratamiento farmacológico , Percepción de Quorum , Diazometano/síntesis química , Diazometano/químicaRESUMEN
Rhodium catalyzed alkyne-tethered intramolecular annulation has been demonstrated for the synthesis of tetracyclic carbazole skeletons and a series of five to eight-membered pyrido[3,2,1-jk]carbazoles were successfully obtained. The present atom economical annulation proceeded under mild reaction conditions, offering a broad substrate scope.
Asunto(s)
Rodio , Rodio/química , Catálisis , Alquinos/química , Carbazoles/químicaRESUMEN
Regulation of Bio-systems in a clean, simple, and efficient way is important for the design of smart bio-interfaces and bioelectronic devices. Light as a non-invasive mean to control the activity of a protein enables spatial and temporal control far superior to other chemical and physical methods. The ability to regulate the activity of a catalytic enzyme in a biofuel-cell reduces the waste of resources and energy and turns the fuel-cell into a smart and more efficient device for power generation. Here we present a microbial-fuel-cell based on a surface displayed, photo-switchable alcohol dehydrogenase. The enzyme was modified near the active site using non-canonical amino acids and a small photo-reactive molecule, which enables reversible control of enzymatic activity. Depending on the modification site, the enzyme exhibits reversible behavior upon irradiation with UV and visible light, in both biochemical, and electrochemical assays. The change observed in power output of a microbial fuel cell utilizing the modified enzyme was almost five-fold, between inactive and active states.
Asunto(s)
Alcohol Deshidrogenasa/metabolismo , Fuentes de Energía Bioeléctrica , Enzimas Inmovilizadas/metabolismo , Luz , ElectricidadRESUMEN
A Cu-catalyzed new sequence involving the Ullmann type intermolecular C-C followed by an intramolecular C-N coupling and then intramolecular aza-Michael type addition (and oxidation) in a single pot afforded various fused N-heterocyclic acetic acid derivatives as inhibitors of PDE4.
Asunto(s)
Ácido Acético/síntesis química , Compuestos Heterocíclicos/síntesis química , Ácido Acético/química , Catálisis , Cobre/química , Compuestos Heterocíclicos/química , Modelos Moleculares , Estructura MolecularRESUMEN
A concise route for the synthesis of dihydrobenzo[j]phenanthridinones has been disclosed through an aryne annulation strategy under metal-free reaction conditions. The reaction involves multiple C-C and C-N bond cleavages/formations via Diels-Alder reaction, aromatization-driven C-N bond cleavage, and amide formation.
RESUMEN
Aryne insertion reaction with 2-aroyl malonates/cyanoesters lead to the formation of diarylmethane or chromones depending on the substitution on the aryne ring. The presence of an electronegative atom at the ortho position of arynes generates chromones, whereas other arynes lead to the formation of diarylmethanes, via a cascade double aryne insertion.
RESUMEN
Novel thieno[3,2-c]pyran-4-one based small molecules were designed as potential anticancer agents. Expeditious synthesis of these compounds was carried out via a multi-step sequence consisting of few steps such as Gewald reaction, Sandmeyer type iodination, Sonogashira type coupling followed by iodocyclization and then Pd-mediated various C-C bond forming reactions. The overall strategy involved the construction of thiophene ring followed by the fused pyranone moiety and then functionalization at C-7 position of the resultant thieno[3,2-c]pyran-4-one framework. Some of the compounds synthesized showed selective growth inhibition of cancer cells in vitro among which two compounds for example, 5d and 6c showed IC(50) values in the range of 2.0-2.5 µM. The crystal structure analysis of an active compound along with hydrogen bonding patterns and molecular arrangement present within the molecule is described.
Asunto(s)
Antineoplásicos/síntesis química , Piranos/química , Bibliotecas de Moléculas Pequeñas/química , Antineoplásicos/química , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Línea Celular , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Células Hep G2 , Humanos , Enlace de Hidrógeno , Conformación Molecular , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/toxicidad , Tiofenos/químicaRESUMEN
A rapid and direct access to N-aryl substituted fused triazinone derivatives has been accomplished via N-arylation of 1,2,3-triazin-4-one ring involving a Cu-mediated coupling between triazinone derivatives and aryl boronic acids. A combination of Cu(OAc)(2)-Et(3)N in 1,2-dichloroethane was found to be effective and various fused triazinone derivatives have been prepared by using this methodology. Molecular structure of a representative compound was confirmed by single crystal X-ray diffraction study. The scope and limitations of this reaction is discussed. Some of the compounds synthesized were tested for chorismate mutase inhibitory properties in vitro. The in vitro dose response study of an active compound is presented.
Asunto(s)
Corismato Mutasa/antagonistas & inhibidores , Cobre/química , Inhibidores Enzimáticos/farmacología , Compuestos Organometálicos/química , Triazinas/farmacología , Catálisis , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Modelos Moleculares , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad , Triazinas/síntesis química , Triazinas/químicaRESUMEN
Molecular iodine facilitated the reaction of 5,5-dimethyl-1,3-cyclohexanedione with aromatic aldehydes in iso-propanol affording a variety of 1,8-dioxo-octahydroxanthenes in high yields. Most of the compounds synthesized showed good anti-proliferative properties in vitro against three cancer cell lines and 9-(2-hydroxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione possessing a 2-hydroxy phenyl group at C-9 position was found to be promising. Further structure elaboration of the same compound and the crystal structure analysis and hydrogen bonding patterns of another compound that is, 9-(4-methoxyphenyl)-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione prepared by using this methodology is presented.
Asunto(s)
Antineoplásicos/síntesis química , Yodo/química , Xantenos/síntesis química , Aldehídos/química , Antineoplásicos/farmacología , Catálisis , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Ciclohexanos/química , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Enlace de Hidrógeno , Concentración 50 Inhibidora , Estructura Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Xantenos/farmacologíaRESUMEN
Novel thieno[2,3-d]pyrimidines containing a cyclohexane ring fused with a six- or five-membered heterocyclic moiety along with a benzylic nitrile were designed as potential inhibitors of PDE4. Expeditious synthesis of these compounds was carried out via a multi-step sequence consisting of a few key steps such as Gewald reaction, Dieckmann type cyclisation and Krapcho decarboxylation. This newly developed strategy involved construction of the thienopyrimidine ring followed by the cyclohexanone moiety and subsequently the fused heterocyclic ring. A number of thieno[2,3-d]pyrimidine based derivatives were synthesized using this method some of which showed promising PDE4B inhibitory properties. One of them was tested for PDE4D inhibition in vitro and dose dependent inhibition of TNF-α. A few selected molecules were docked into the PE4B protein the results of which showed good overall correlations to their observed PDE4B inhibitory properties in vitro. The crystal structure analysis of representative compounds along with hydrogen bonding patterns and molecular arrangement present within the molecule is described.
Asunto(s)
Pirimidinas/química , Tiofenos/química , Animales , Línea Celular , Cristalografía por Rayos X , Ciclohexanonas/química , Humanos , Enlace de Hidrógeno , Ratones , Modelos Moleculares , Inhibidores de Fosfodiesterasa 4/síntesis química , Inhibidores de Fosfodiesterasa 4/química , Inhibidores de Fosfodiesterasa 4/farmacología , Pirimidinas/síntesis química , Pirimidinas/farmacología , Tiofenos/síntesis química , Tiofenos/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/química , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
A series of novel N-aryl substituted thieno[2,3-d]pyrimidin-4(3H)-ones were designed and synthesized as potential inhibitors of chorismate mutase. Synthesis of this class of compounds was carried out by using Cu-mediated C-N bond forming reaction between thieno[2,3-d]pyrimidin-4(3H)-ones and aryl boronic acids. The reaction can be performed in an open flask as the conversion was found to be not sensitive to the presence of air or atmospheric moisture. A range of compounds were prepared by using this method and single crystal X-ray diffraction study was performed using a representative compound. In vitro pharmacological data of some of the compounds synthesized along with dose response studies using active molecules are presented. In silico interactions of these molecules with chorismate mutase are also presented.
Asunto(s)
Corismato Mutasa/antagonistas & inhibidores , Cobre/química , Inhibidores Enzimáticos/farmacología , Compuestos Organometálicos/química , Pirimidinonas/farmacología , Catálisis , Corismato Mutasa/genética , Corismato Mutasa/metabolismo , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Modelos Moleculares , Estructura Molecular , Mycobacterium tuberculosis/enzimología , Pirimidinonas/síntesis química , Pirimidinonas/química , Relación Estructura-ActividadRESUMEN
A serendipitous synthesis of N-substituted 2-amino-2'-hydroxy-1,1'-biaryls through an aryne annulation with indolyl ß-ketonitrile/ester in a cascade manner is demonstrated. The reaction sequence involves benzyne-mediated [2 + 2] Stoltz-type cycloaddition-cleavage and intramolecular Michael addition followed by C-N bond cleavage under transition-metal-free reaction conditions. Interestingly, while [4 + 2] Diels-Alder reaction is a possible pathway, no traces of the regioisomer was isolated.
RESUMEN
Phospho-ceramide analogue-1 (PCERA-1), a synthetic analogue of ceramide-1-phosphate (C1P), has been previously shown to act as a potent modulator of macrophage activity and inflammation. We have developed an efficient synthesis of PCERA-1 from readily available starting materials, and designed and prepared derivatives of this analogue, including a photoaffinity probe to tag and identify putative proteins that bind PCERA-1.
Asunto(s)
Ceramidas/farmacología , Inmunomodulación/efectos de los fármacos , Macrófagos/efectos de los fármacos , Sondas Moleculares/farmacología , Animales , Ceramidas/síntesis química , Ceramidas/química , Relación Dosis-Respuesta a Droga , Lipopolisacáridos/farmacología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Sondas Moleculares/síntesis química , Sondas Moleculares/química , Estructura Molecular , Procesos Fotoquímicos , Células RAW 264.7 , Relación Estructura-ActividadRESUMEN
A Cu-mediated unprecedented cascade reaction in the presence of air afforded a conceptually new synthesis of 2,2'-spirobiindole derivatives. This reaction proceeds via the rearrangement of several bonds in a cyclopenta[b]indole framework including a facial selective intramolecular ring closure. The potential of this method is highlighted in the straightforward and single step synthesis of a paullone like compound.
RESUMEN
A conceptually new and general strategy has been developed for the construction of a benzimidazole or a benzoxazole ring fused with isoquinolinone affording a diverse and unique class of small molecules as potential and novel inhibitors of PDE4.
Asunto(s)
Bencimidazoles/química , Benzoxazoles/química , Isoquinolinas/química , Inhibidores de Fosfodiesterasa 4/química , Ciclización , Resinas de Intercambio Iónico/química , Estirenos/químicaRESUMEN
A rapid, versatile and one-pot Cu-mediated domino reaction has been developed for facile assembly of two six membered fused N-heterocyclic rings leading to novel small molecules as potential inhibitors of PDE4.
RESUMEN
A conceptually new and straightforward introduction of sulfonyl groups at the C-7 position of an indole ring has been achieved via AlCl(3) mediated unexpected regioselective sulfonyl group migration for N-alkyl/aryl/heteroarylsulfonyl indoles affording potential inhibitors of Mycobacterium tuberculosis H37Rv chorismate mutase.