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ETHNOPHARMACOLOGICAL RELEVANCE: Dried roots of Peucedanum decursivum, a traditional Chinese medicine (TCM), has historically respiratory diseases such as cough, thick phlegm, headache, fever, and gynecological diseases, rheumatoid arthritis, and nasopharyngeal carcinoma. AIM OF THE STUDY: Made an endeavor to evaluate the research trajectory of P. decursivum, comprehensively discern its developmental status, and offer a guideline for future investigations. MATERIALS AND METHODS: A meticulous search of literatures and books from 1955 to 2024 via databases like PubMed, Web of Science and CNKI was conducted, including topics and keywords of " P. decursivum" "Angelica decursivum" and "Zihua Qianhu". RESULTS: P. decursivum and its prescriptions have traditionally been used for treating phlegm-heat cough, wind-heat cough, gastrointestinal diseases, pain relief and so on. It contains 234 identified compounds, encompassing coumarins, terpenes, volatile oils, phenolic acids, fatty acids and derivatives. It exhibits diverse pharmacological activities, including anti-asthmatic, anti-inflammatory, antioxidant effects, anti-hypertensive, anti-diabetic, anti-Alzheimer, and anti-cancer properties, primarily attributed to coumarins. Microscopic identification, HPLC fingerprinting, and bioinformatics identification are the primary methods currently used for the quality control. CONCLUSION: P. decursivum demonstrates anti-asthmatic, anti-inflammatory, and antioxidant effects, aligning with its traditional use. However, experimental validation of its efficacy against phlegm and viruses is needed. Additionally, analgesic effects mentioned in historical texts lack modern pharmacological studies. Numerous isolated compounds exhibit highly valuable medicinal properties. Future research can delve into exploring these substances further. Rigorous of heavy metal contamination, particularly Cd and Pb, is necessary. Simultaneously, investigating its pharmacokinetics and toxicity in humans is crucial for the safety.
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Apiaceae , Etnobotánica , Etnofarmacología , Fitoquímicos , Control de Calidad , Humanos , Fitoquímicos/farmacología , Fitoquímicos/química , Fitoquímicos/uso terapéutico , Apiaceae/química , Animales , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional China/métodosRESUMEN
Ovarian cancer (OC) is one of the most lethal gynecologic cancers that is typically diagnosed at the very late stage of disease progression. Thus, there is an unmet need to develop diagnostic probes for early detection of OC. One approach may rely on RNA as a molecular biomarker. In this regard, FLJ22447 lncRNA is an RNA biomarker that is over-expressed in ovarian cancer (OC) and in cancer-associated fibroblasts (CAFs). CAFs appear early on in OC as they provide a metastatic niche for OC progression. FIT-PNAs (forced intercalation-peptide nucleic acids) are DNA analogs that are designed to fluoresce upon hybridization to their complementary RNA target sequence. In recent studies, we have shown that the introduction of cyclopentane PNAs into FIT-PNAs (cpFIT-PNA) results in superior RNA sensors. Herein, we report the design and synthesis of cpFIT-PNAs for the detection of this RNA biomarker in living OC cells (OVCAR8) and in CAFs. cpFIT-PNA was compared to FIT-PNA and the cell-penetrating peptide (CPP) of choice was either a simple one (four L-lysines) or a CPP with enhanced cellular uptake (CLIP6). The combination of CLIP6 with cpFIT-PNA resulted in a superior sensing of FLJ22447 lncRNA in OVCAR8 cells as well as in CAFs. Moreover, incubation of CLIP6-cpFIT-PNA in OVCAR8 cells leads to a significant decrease (ca. 60%) in FLJ22447 lncRNA levels and in cell viability, highlighting the potential theranostic use of such molecules.
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Ciclopentanos , Neoplasias Ováricas , Ácidos Nucleicos de Péptidos , ARN Largo no Codificante , Humanos , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Femenino , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ácidos Nucleicos de Péptidos/química , Ciclopentanos/química , Ciclopentanos/farmacología , Línea Celular Tumoral , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismoRESUMEN
Activation of silencing gene clusters is an important way to discover structurally novel compounds. In this study, three undescribed compounds were obtained from an engineered strain of Streptomyces sp. S35-LAL1. They include a polysubstituted cyclopentane with an unprecedented 10-carbon skeleton (1) and two glycerol esters (2 and 3). The structures of compounds 1-3 were elucidated through analysis of their spectroscopic data including 1D, 2D NMR, optical rotation, and electronic circular dichroism (ECD).
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The performance of blue quantum dot light-emitting diodes (QLEDs) is limited by unbalanced charge injection, resulting from insufficient holes caused by low mobility or significant energy barriers. Here, we introduce an angular-shaped heteroarene based on cyclopentane[b]thiopyran (C8-SS) to modify the hole transport layer poly-N-vinylcarbazole (PVK), in blue QLEDs. C8-SS exhibits high hole mobility and conductivity due to the π···π and S···π interactions. Introducing C8-SS to PVK significantly enhanced hole mobility, increasing it by 2 orders of magnitude from 2.44 × 10-6 to 1.73 × 10-4 cm2 V-1 s-1. Benefiting from high mobility and conductivity, PVK:C8-SS-based QLEDs exhibit a low turn-on voltage (Von) of 3.2 V. More importantly, the optimized QLEDs achieve a high peak power efficiency (PE) of 7.13 lm/W, which is 2.65 times that of the control QLEDs. The as-proposed interface engineering provides a novel and effective strategy for achieving high-performance blue QLEDs in low-energy consumption lighting applications.
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We reported a chiral oxamide-phosphine ligand (COAP-Ph)-Pd-catalyzed asymmetric [3+2] cycloaddition reaction between vinyl cyclopropane compounds derived from 1,3-indanedione and 2-vinylcyclopropane-1,1-dicarboxylates with cyclic sulfonyl 1-azadienes. The corresponding reactions provided a series of enantiomerically active spiro cyclopentane-indandione and cyclopentane structures bearing three consecutive stereogenic centers in good yields with good diastereo- and enantioselectivity. The COAP-Pd complex serves not only to promote generation of chiral π-allyl-palladium intermediates and induce the asymmetry of the reaction, but also depress the background reaction.
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Conformational search and density functional theory calculations were performed to explore the preferences of helical structures for chiro-specific oligo-γ-peptides of 2-(aminomethyl)cyclopentanecarboxylic acid (γAmc5) with a cyclopentyl constraint on the Cα-Cß bond in solution. The dimer and tetramer of γAmc5 (1) with homochiral (1S, 2S) configurations exhibited a strong preference for the 9-membered helix foldamer in solution, except for the tetramer in water. However, the oligomers of γAmc5 (1) longer than tetramer preferentially adopted a right-handed (P)-2.614-helix (H1-14) as the peptide sequence becomes longer and as solvent polarity increases. The high stabilities for H1-14 foldamers of γAmc5 (1) in solution were ascribed to the favored solvation free energies. The calculated mean backbone torsion angles for H1-14 helix foldamers of γAmc5 (1) were similar to those calculated for oligomers of other γ-residues with cyclopentane or cyclohexane rings. However, the substitution of cyclopentane constraints on the Cα-Cß bond of the γAmc5 (1) residue resulted in different conformational preferences and/or handedness of helix foldamers. In particular, the pyrrolidine-substituted analogs of the H1-14 foldamers of γAmc5 (1) with adjacent amine diads substituted at a proximal distance are expected to be potential catalysts for the crossed aldol condensation in nonpolar and polar solvents.
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Ciclopentanos , Péptidos , Ciclopentanos/química , Péptidos/química , Estructura Secundaria de Proteína , Ácidos Carboxílicos/química , Termodinámica , Modelos MolecularesRESUMEN
Hydrate-based desalination (HBD) shows promise as a freshwater production technology for saline water. Liquid-phase hydrate formers, with their ability to facilitate hydrate formation at atmospheric pressure, have gained attention for their high energy efficiency in HBD. This study explored cyclopentane (CP) HBD by experimentally measuring the thermodynamic properties of CP hydrate in saline solutions and developing a theoretical framework to estimate the water yield of CP HBD under various operating conditions. The measured dissociation enthalpy of CP hydrate was found to be 12 % and 22 % lower compared to those of propane and R134a hydrates, respectively. The equilibrium dissociation temperatures of CP hydrate at different NaCl concentrations under atmospheric pressure were experimentally measured and then predicted using the Hu-Lee-Sum correlation. The theoretically achievable maximum salinity and water yield for CP HBD were calculated in the temperature range of 268-280 K and the initial salinity range of 0-8 wt.%. Additionally, the concept of HBD heat efficiency, representing the maximum amount of pure water producible per unit of heat, was introduced to identify an optimal operating condition for the HBD process. Efficiency-maximized temperatures, where the HBD heat efficiency reached its peaks, were determined for various initial salinities in the process, for example, 273.4 K for NaCl 3.5 wt.% solution. This novel approach provides invaluable guidance for determining the most energy-efficient operating conditions in the HBD process and establishes a solid foundation for further advancements in this field.
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Ciclopentanos , Cloruro de Sodio , Temperatura , Termodinámica , CalorRESUMEN
Site-directed spin labeling followed by investigation using Electron Paramagnetic Resonance spectroscopy is a rapidly expanding powerful biophysical technique to study structure, local dynamics and functions of biomolecules using pulsed EPR techniques and nitroxides are the most widely used spin labels. Modern trends of this method include measurements directly inside a living cell, as well as measurements without deep freezing (below 70 K), which provide information that is more consistent with the behavior of the molecules under study in natural conditions. Such studies require nitroxides, which are resistant to the action of biogenic reductants and have high spin relaxation (dephasing) times, Tm. (1R(S),5R(S),7R(S),8R(S))-1,8-bis(hydroxymethyl)-6-azadispiro[4.1.4.2]tridecane-6-oxyl is a unique nitroxide that combines these features. We have developed a convenient method for the synthesis of this radical and studied the ways of its functionalization. Promising spin labels have been obtained, the parameters of their spin relaxation T1 and Tm have been measured, and the kinetics of reduction with ascorbate have been studied.
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Óxidos de Nitrógeno , Marcadores de Spin , Espectroscopía de Resonancia por Spin del Electrón/métodos , Óxidos de Nitrógeno/químicaRESUMEN
The development of novel polymerization capable of yielding polymers with low molecular weight distribution (D) is essential and significant in polymer chemistry, where monofunctional initiator contains only one initiation site in these polymerizations generally. Here, ketyl radical anion species is introduced to develop a novel Ketyl Mediated Polymerization (KMP), which enables radical polymerization at carbon radical site and anionic ring-opening polymerization at oxygen anion site, respectively. Meanwhile, polymerization and corresponding organic synthesis generally couldn't be performed simultaneously in one pot. Through KMP, organic synthesis and polymerization are achieved in one pot, where small molecules (cyclopentane derivates) and polymers with low D are successfully prepared under mild condition simultaneously. At the initiation step, both organic synthesis and polymerization are initiated by single electron transfer reaction with ketyl radical anion formation. Cyclopentane derivates are synthesized through 3-3 coupling reaction and cyclization. Polystyrene and polycaprolactone with low D and a full monomer conversion are prepared by KMP via radical polymerization and anionic ring-opening polymerization, respectively. This work therefore enables both organic synthesis and two different polymerizations from same initiation system, which saves time, labour, resource and energy and expands the reaction mode and method libraries of organic chemistry and polymer chemistry.
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Resins have enormous potential in the removal of naphthenic acids (NAs) from transformer oil due to their rich porosity and high mechanical and diversified functionality, whereas their poor adsorption capacity limits application. In this work, the polystyrene-diethylamine resin (PS-DEA-x) was prepared by grafting diethylamine (DEA) onto chloromethylated polystyrene (PS-Cl) resin to efficiently adsorb cyclopentane carboxylic acid from transformer oil for the first time. The characterization analysis results indicated that amine contents were significantly enhanced with the increase in DEA. Particularly, resin with a molar ratio of 1:5 depending on chloromethyl to DEA (PS-DEA-5) exhibited the highest amine contents and efficient adsorption of cyclopentane carboxylic acid (static adsorption capacity up to 110.0 mg/g), which was about 5 times higher than that of the pristine PS-Cl. The thermodynamic and kinetic studies showed that the adsorption behaviors could be well fitted to the Langmuir isotherm equation and pseudo-second-order rate equation. Moreover, it was found that 1 g of the PS-DEA-5 can decontaminate about 760 mL transformer oil to meet reuse standards by a continuous stream, indicating its potential application in industry.
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An asymmetric Michael reaction between cyclopentane-1,2-dione and alkylidene oxindole was studied in the presence of a multifunctional squaramide catalyst. Michael adducts were obtained in high enantioselectivities and in moderate diastereoselectivities.
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At present, the reactivity of cyclic alkanes is estimated by comparison with acyclic hydrocarbons. Due to the difference in the structure of cycloalkanes and acycloalkanes, the thermodynamic data obtained by analogy are not applicable. In this study, a molecular beam sampling vacuum ultraviolet photoionization time-of-flight mass spectrometer (MB-VUV-PI-TOFMS) was applied to study the low-temperature oxidation of cyclopentane (CPT) at a total pressure range from 1-3â atm and low-temperature range between 500 and 800â K. Low-temperature reaction products including cyclic olefins, cyclic ethers, and highly oxygenated intermediates (e. g., ketohydroperoxide KHP, keto-dihydroperoxide KDHP, olefinic hydroperoxides OHP and ketone structure products) were observed. Further investigation of the oxidation of CPT - electronic structure calculations - were carried out at the UCCSD(T)-F12a/aug-cc-pVDZ//B3LYP/6-31+ G(d,p) level to explore the reactivity of O2 molecules adding sequentially to cyclopentyl radicals. Experimental and theoretical observations showed that the dominant product channel in the reaction of CPT radicals with O2 is HO2 elimination yielding cyclopentene. The pathways of second and third O2 addition - the dissociation of hydroperoxide - were further confirmed. The results of this study will develop the low-temperature oxidation mechanism of CPT, which can be used for future research on accurately simulating the combustion process of CPT.
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ObjectiveIn order to find a fast odor-based method for the identification of sulfur fumigated Gastrodiae Rhizoma, an ultra-fast gas phase electronic nose technology was used to identify the odors of different degrees of sulfur fumigated Gastrodiae Rhizoma decoction pieces. MethodHeracles NEO ultra-fast gas phase electronic nose was employed to collect gas chromatograms of unsulfured and sulfured with different degrees of Gastrodiae Rhizoma decoction pieces, gas chromatograms were performed under programmed temperature (initial temperature of 40 ℃, 0.2 ℃·s-1 to 60 ℃, and then 4 ℃·s-1 to 250 ℃), the sample volume was 5 mL, the incubation temperature was 65 ℃ and incubation time was 35 min. Kovats retention index and the AroChemBase database were used for qualitative analysis, and stoichiometric analysis was performed on this basis. Principal component analysis (PCA), discriminant factor analysis (DFA) and partial least squares-discriminant analysis (PLS-DA) models were established to identify the Gastrodiae Rhizoma decoction pieces with different degrees of sulfur fumigation. ResultAccording to the comparative analysis of AroChemBase database, there were significant differences in the odor characteristics of sulfur fumigated and non-sulfur fumigated Gastrodiae Rhizoma, cyclopentane, acetone and heptane might be the odor components to distinguish the degree of sulfur fumigation in Gastrodiae Rhizoma decoction pieces. The identification index of PCA model was 81, the accumulative discriminant index of the discriminating factors was 92.09% in DFA model, the supervisory model interpretation rate of PLS-DA model was 0.963 and the predictive ability parameter was 0.956, indicating that PCA, DFA and PLS-DA models could well distinguish Gastrodiae Rhizoma decoction pieces with different sulfur fumigation degrees. ConclusionHeracles NEO ultra-fast gas phase electronic nose can be used as a rapid method to identify and distinguish Gastrodiae Rhizoma decoction pieces with different levels of sulfur fumigation. Meanwhile, it can provide a rapid, simple and green method and technology for identification of traditional Chinese medicine decoction pieces by sulfur fumigation.
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The mol-ecule of the title compound, C24H16Cl12N2O4, is generated by a crystallographic inversion centre at the midpoint of the central C-C bond. A kink in the mol-ecule is defined by a torsion angle of -169.86â (15)° about this central bond of the alkyl bridge. The pyrrolidine ring is essentially planar [max. deviation = 0.014â (1)â Å]. The cyclo-hexane ring has a boat conformation, while both cyclo-pentane rings adopt an envelope conformation. In the crystal structure, mol-ecules are linked by inter-molecular C-Hâ¯O, C-Hâ¯Cl and C-Clâ¯π inter-actions, and short inter-molecular Clâ¯O and Clâ¯Cl contacts, forming a three-dimensional network.
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A Brønsted acid-catalyzed domino ring-opening cyclization transformation of donor-acceptor (D-A) cyclopropanes and 2-naphthols has been developed. This formal [3+2] cyclization reaction provided novel and efficient access to the naphthalene-fused cyclopentanes in the absence of any transition-metal catalysts or additives. This robust procedure was completed smoothly on a gram-scale to afford the corresponding product with comparable efficiency. Furthermore, the synthetic application of the prepared product has been demonstrated by its transformation into a variety of synthetically useful molecules.
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This review focuses on the rare group of carbon-bridged steroids (CBS) and triterpenoids found in various natural sources such as green, yellow-green, and red algae, marine sponges, soft corals, ascidians, starfish, and other marine invertebrates. In addition, this group of rare lipids is found in amoebas, fungi, fungal endophytes, and plants. For convenience, the presented CBS and triterpenoids are divided into four groups, which include: (a) CBS and triterpenoids containing a cyclopropane group; (b) CBS and triterpenoids with cyclopropane ring in the side chain; (c) CBS and triterpenoids containing a cyclobutane group; (d) CBS and triterpenoids containing cyclopentane, cyclohexane or cycloheptane moieties. For the comparative characterization of the antitumor profile, we have added several semi- and synthetic CBS and triterpenoids, with various additional rings, to identify possible promising sources for pharmacologists and the pharmaceutical industry. About 300 CBS and triterpenoids are presented in this review, which demonstrate a wide range of biological activities, but the most pronounced antitumor profile. The review summarizes biological activities both determined experimentally and estimated using the well-known PASS software. According to the data obtained, two-thirds of CBS and triterpenoids show moderate activity levels with a confidence level of 70 to 90%; however, one third of these lipids demonstrate strong antitumor activity with a confidence level exceeding 90%. Several CBS and triterpenoids, from different lipid groups, demonstrate selective action on different types of tumor cells such as renal cancer, sarcoma, pancreatic cancer, prostate cancer, lymphocytic leukemia, myeloid leukemia, liver cancer, and genitourinary cancer with varying degrees of confidence. In addition, the review presents graphical images of the antitumor profile of both individual CBS and triterpenoids groups and individual compounds.
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Antineoplásicos/farmacología , Productos Biológicos/farmacología , Carcinogénesis/efectos de los fármacos , Esteroides/farmacología , Triterpenos/farmacología , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Organismos Acuáticos/química , Productos Biológicos/química , Carbono/química , Proliferación Celular/efectos de los fármacos , Chlorophyta/química , Cicloparafinas/química , Cicloparafinas/farmacología , Hongos/química , Humanos , Invertebrados/química , Metabolismo de los Lípidos/efectos de los fármacos , Rhodophyta/química , Esteroides/química , Triterpenos/químicaRESUMEN
Antibiotic resistance is one of the most challenging global health issues and presents an urgent need for the development of new antibiotics. In this regard, phospho-MurNAc-pentapeptide translocase (MraY), an essential enzyme in the early stages of peptidoglycan biosynthesis, has emerged as a promising new antibiotic target. We recently reported the crystal structures of MraY in complex with representative members of naturally occurring nucleoside antibiotics, including muraymycin D2. However, these nucleoside antibiotics are synthetically challenging targets, which limits the scope of medicinal chemistry efforts on this class of compounds. To gain access to active muraymycin analogs with reduced structural complexity and improved synthetic tractability, we prepared and evaluated cyclopentane-based muraymycin analogs for targeting MraY. For the installation of the 1,2-syn-amino alcohol group of analogs, the diastereoselective isocyanoacetate aldol reaction was explored. The structure-activity relationship analysis of the synthesized analogs suggested that a lipophilic side chain is essential for MraY inhibition. Importantly, the analog 20 (JH-MR-23) showed antibacterial efficacy against Staphylococcus aureus. These findings provide insights into designing new muraymycin-based MraY inhibitors with improved chemical tractability.
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Antibacterianos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Ciclopentanos/farmacología , Transferasas/antagonistas & inhibidores , Uridina/análogos & derivados , Uridina/farmacología , Antibacterianos/síntesis química , Arginina/análogos & derivados , Arginina/farmacología , Ciclopentanos/síntesis química , Pruebas de Enzimas , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Transferasas (Grupos de Otros Fosfatos Sustitutos)RESUMEN
In this study, series of non-ionic surfactants from Span and Tween are evaluated for their ability to affect the viscosity profile of cyclopentane hydrate slurry. The surfactants; Span 20, Span 40, Span 80, Tween 20, Tween 40 and Tween 80 were selected and tested to provide different hydrophilic-hydrophobic balance values and allow evaluation their solubility impact on hydrate formation and growth time. The study was performed by using a HAAKE ViscotesterTM 500 at 2 °C and a surfactant concentration ranging from 0.1 wt%-1 wt%. The solubility characteristic of the non-ionic surfactants changed the hydrate slurry in different ways with surfactants type and varying concentration. The rheological measurement suggested that oil-soluble Span surfactants was generally inhibitive to hydrate formation by extending the hydrate induction time. However, an opposite effect was observed for the Tween surfactants. On the other hand, both Span and Tween demonstrated promoting effect to accelerate hydrate growth time of cyclopentane hydrate formation. The average hydrate crystallization growth time of the blank sample was reduced by 86% and 68% by Tween and Span surfactants at 1 wt%, respectively. The findings in this study are useful to understand the rheological behavior of surfactants in hydrate slurry.
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Ciclopentanos/química , Interacciones Hidrofóbicas e Hidrofílicas , Reología , Tensoactivos/química , Agua/química , Solubilidad , ViscosidadRESUMEN
RORγt is the master regulator of the IL-23/IL-17 axis, a pathway that is clinically validated for the treatment of various immunological disorders. Over the last few years, our group has reported different chemotypes that potently act as inverse agonists of RORγt. One of them, the tricyclic pyrrolidine chemotype, has demonstrated biologic-like preclinical efficacy and has led to our clinical candidate BMS-986251. In this letter, we discuss the invention of an annulation reaction which enabled the synthesis of a tricyclic exocyclic amide chemotype and the identification of compounds with RORγt inverse agonist activity. Preliminary structure activity relationships are disclosed.
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Amidas/química , Hidrocarburos Cíclicos/química , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/antagonistas & inhibidores , Sulfonas/química , Amidas/síntesis química , Amidas/metabolismo , Animales , Ciclización , Agonismo Inverso de Drogas , Humanos , Hidrocarburos Cíclicos/síntesis química , Hidrocarburos Cíclicos/metabolismo , Ratones , Microsomas Hepáticos/metabolismo , Simulación del Acoplamiento Molecular , Estructura Molecular , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Relación Estructura-Actividad , Sulfonas/síntesis química , Sulfonas/metabolismoRESUMEN
A vinyl cyclopropane rearrangement embedded in an iridium-catalyzed hydrogen borrowing reaction enabled the formation of substituted stereo-defined cyclopentanes from Ph* methyl ketone and cyclopropyl alcohols. Mechanistic studies provide evidence for the ring-expansion reaction being the result of a cascade based on oxidation of the cyclopropyl alcohols, followed by aldol condensation with the pentamethyl phenyl-substituted ketone to form an enone containing the vinyl cyclopropane. Subsequent single electron transfer (SET) to this system initiates a rearrangement, and the catalytic cycle is completed by reduction of the new enone. This process allows for the efficient formation of diversely substituted cyclopentanes as well as the construction of complex bicyclic carbon skeletons containing up to four contiguous stereocentres, all with high diastereoselectivity.