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1.
Org Lett ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248691

RESUMEN

There is a resurgence of research interest in inherently chiral calixarenes and heteracalixaromatics. However, the examples of macrocyclic ring-expanded homocalixarenes and heterocalixaromatics of inherent chirality are not known. Here we report an efficient method to construct inherently chiral N2,O2-linked homo-heteracalixaromatics from reductive amination reactions between bis-aldehydes and aliphatic diamines. Examples of post-macrocyclization derivatization were also demonstrated. Enantiomers were obtained from resolution and did not undergo racemization at an elevated temperature. This study provides a new strategy to design novel and functional inherently chiral macrocycles that have potential applications in supramolecular chemistry.

2.
Chem Sci ; 15(31): 12517-12522, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39118627

RESUMEN

There has been a recent upsurge in research aimed at synthesizing inherently chiral molecules devoid of point, axial, planar and helical chiralities. We present herein our design and enantioselective synthesis of a series of inherently chiral macrocycles. These compounds, termed nor-heteracalixaromatics, feature a biaryl bond that replaces one of the aryl-heteroatom-aryl linkages found in classic heteracalix[4]aromatics. Macrocyclization of linear achiral substrates via an intramolecular Suzuki-Miyaura cross-coupling reaction affords the 15-membered cyclophane without any chiral elements in high yields and enantioselectivities. Notably, the formation of the aryl-aryl bond does not induce axial chirality at the biaryl linkage. Instead, it restricts the free rotation of an aromatic ring located four bonds away, leading to the inherent chirality of the macrocycle. The intriguing chiroptical properties of these compounds made them promising platform for the development of CPL emitters.

3.
ACS Appl Mater Interfaces ; 16(35): 46538-46547, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39087831

RESUMEN

The development of wearable electronic devices for human health monitoring requires materials with high mechanical performance and sensitivity. In this study, we present a novel transparent tissue-like ionogel-based wearable sensor based on silver nanowire-reinforced ionogel nanocomposites, P(AAm-co-AA) ionogel-Ag NWs composite. The composite exhibits a high stretchability of 605% strain and a moderate fracture stress of about 377 kPa. The sensor also demonstrates a sensitive response to temperature changes and electrostatic adsorption. By encapsulating the nanocomposite in a polyurethane transparent film dressing, we address issues such as skin irritation and enable multidirectional stretching. Measuring resistive changes of the ionogel nanocomposite in response to corresponding strain changes enables its utility as a highly stretchable wearable sensor with excellent performance in sensitivity, stability, and repeatability. The fabricated pressure sensor array exhibits great proficiency in stress distribution, capacitance sensing, and discernment of fluctuations in both external electric fields and stress. Our findings suggest that this material holds promise for applications in wearable and flexible strain sensors, temperature sensors, pressure sensors, and actuators.


Asunto(s)
Nanocompuestos , Nanocables , Plata , Dispositivos Electrónicos Vestibles , Plata/química , Nanocompuestos/química , Nanocables/química , Humanos , Geles/química , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Poliuretanos/química
4.
J Inflamm Res ; 17: 4175-4186, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38979433

RESUMEN

Purpose: Microwave ablation (MWA) is a minimally invasive technique for treating lung cancer. It can induce immune response; however, its effect on the immune microenvironment in tumor-draining lymph nodes (TdLN) is not well understood. This study aims to identify changes in the immune microenvironment in TdLN following MWA in a Lewis lung cancer (LLC) mouse model. Methods: LLC mouse model was established and followed by MWA. TdLN were collected at various time points, including pre-MWA and days 1, 2, 4, and 8 post-MWA. Flow cytometry was used to determine the frequencies of CD4+ T cells, CD8+ T cells, regulatory T (Treg) cells, natural killer (NK) cells, dendritic cells (DCs) and other immune cells in the TdLN. Certain cytokines were also detected. Results: Compared with pre-MWA, the frequency of CD4+ T cells significantly increased from day 1 to day 8 post-MWA. The frequency of CD8+ T cells decreased significantly on days 2 and 4, but no significant changes occurred on days 1 and 8. Significant decreases in the frequencies of Treg cells and Klrg1+ Treg cells were observed from day 1 to day 4. On days 4 and 8, there was a significant increase in the frequency of NK cells. The frequency of resident cDC2 significantly increased on day 4, whereas CD11b+ migratory cDCs increased on day 1. Additionally, on day 4, a notable rise was observed in the frequency of NK cells secreting IFN-γ, while on day 8, there was a significant increase in the frequency of CD8+ T cells secreting both IFN-γ and TNF-α. Conclusion: MWA of lung cancer can alter the immune microenvironment in the TdLN, triggering immune responses. These changes are particularly evident and intricate within the initial 4 days post-MWA. Treatment combined with MWA within a certain period may significantly enhance anti-tumor immunity.

5.
Medicine (Baltimore) ; 103(30): e38947, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39058857

RESUMEN

BACKGROUND: Uric acid, as an important antioxidant substance in human body, has attracted much attention in relation to the risk of Parkinson's disease (PD). However, the causal relationship between them is still controversial. We perform a meta-analysis to summarize the available evidence from cohort studies on the association between high uric acid and the risk of PD. METHODS: We searched the Cochrane Library, PubMed, Medline, and Embase to obtain the Odds Ratio (OR) of high uric acid and PD and pooled the data using RevMan software (v5.4; Cochrane library). RESULTS: A total of 18 studies involving more than 840,774 participants were included. Overall, we found a significant association (OR = 0.84; 95% CI: 0.77-0.91) between high uric acid and PD. Subgroup analysis was stratified by gender, indicating more statistically significant protective effects of serum urate in men (OR = 0.66; 95% CI: 0.54-0.81) than that of in women (OR = 0.86; 95% CI: 0.76-0.98). People under the age of 60 (OR = 0.53, 95% CI: 0.33-0.86) are more likely to benefit from high uric acid than people over age of 60 (OR = 0.73, 95% CI: 0.63-0.86). The resistance of high uric acid to PD in LRRK2 mutation carriers (OR = 0.22, 95% CI: 0.11-0.45) is stronger than that in non-manifesting LRRK2 mutation carriers (OR = 0.37, 95% CI: 0.16-0.85). In addition, a dose-response trend of serum urate to reduce PD risk was also observed (OR = 0.68; 95% CI: 0.48-0.93). CONCLUSION: Our study confirms a significant association between high uric acid and the risk of PD, especially in men under 60 years old, and a dose-response trend of uric acid to reduce PD risk was also observed. Furthermore, LRRK2 mutation carriers are more likely to benefit from high uric acid than non-manifesting LRRK2 mutation carriers.


Asunto(s)
Enfermedad de Parkinson , Ácido Úrico , Humanos , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/genética , Ácido Úrico/sangre , Masculino , Femenino , Factores de Riesgo , Persona de Mediana Edad , Factores Sexuales , Hiperuricemia/epidemiología , Hiperuricemia/sangre , Factores de Edad
6.
Nature ; 631(8020): 313-318, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38898283

RESUMEN

Glassy polymers are generally stiff and strong yet have limited extensibility1. By swelling with solvent, glassy polymers can become gels that are soft and weak yet have enhanced extensibility1-3. The marked changes in properties arise from the solvent increasing free volume between chains while weakening polymer-polymer interactions. Here we show that solvating polar polymers with ionic liquids (that is, ionogels4,5) at appropriate concentrations can produce a unique class of materials called glassy gels with desirable properties of both glasses and gels. The ionic liquid increases free volume and therefore extensibility despite the absence of conventional solvent (for example, water). Yet, the ionic liquid forms strong and abundant non-covalent crosslinks between polymer chains to render a stiff, tough, glassy, and homogeneous network (that is, no phase separation)6, at room temperature. Despite being more than 54 wt% liquid, the glassy gels exhibit enormous fracture strength (42 MPa), toughness (110 MJ m-3), yield strength (73 MPa) and Young's modulus (1 GPa). These values are similar to those of thermoplastics such as polyethylene, yet unlike thermoplastics, the glassy gels can be deformed up to 670% strain with full and rapid recovery on heating. These transparent materials form by a one-step polymerization and have impressive adhesive, self-healing and shape-memory properties.

7.
J Cancer Res Ther ; 20(2): 669-677, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38687939

RESUMEN

OBJECTIVES: This study aimed to investigate the presence of stem-like CD8 T (CD8 TSL) cells in lung adenocarcinoma (LUAD) and explore their relationships with the clinical outcomes. METHODS: Multiplex immunofluorescence (mIF) was performed to identify CD8 TSL and antigen-presenting cells (APC) in 76 LUAD patients. Differences in the number of CD8 TSL cells based on tumor stage and the spatial relationships between CD8 TSL cells and APC niches were determined. The optimal cutoff value of CD8 TSL cells for predicting survival in patients with stage I LUAD was calculated. RESULTS: CD8 TSL cells were present in all tumors, and their numbers were significantly higher in stage I patients than in stage III patients (P = 0.010); CD8 TSL cells located in the APC niches accounted for 69.7% (53/76) of the hotspot fields. The optimal cutoff value for the number of CD8 TSL cells required to predict the overall survival (OS) in patients with stage I LUAD was 2.5 per 10000 µm2. The median OS and progression-free survival (PFS) in the high-level group (>2.5) were significantly (P < 0.001) longer than those in the low-level group (≤2.5). The number of CD8 TSL cells was an independent prognostic factor for stage I LUAD. Patients with more CD8 TSL cells had a lower risk of death and disease progression than those with less CD8 TSL cells. CONCLUSION: CD8 TSL cells were observed in patients with stages I-III LUAD and might serve as prognostic biomarkers for stage I LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Biomarcadores de Tumor , Linfocitos T CD8-positivos , Neoplasias Pulmonares , Estadificación de Neoplasias , Humanos , Pronóstico , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/mortalidad , Linfocitos T CD8-positivos/inmunología , Femenino , Masculino , Persona de Mediana Edad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/inmunología , Biomarcadores de Tumor/metabolismo , Anciano , Adulto
8.
Front Nutr ; 11: 1375060, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38544757

RESUMEN

Background: Metabolic syndrome (MetS) is a global health concern that threatens human well-being. The oxidative balance score (OBS) is a tool to identify the level of oxidative stress that is correlated with MetS risk. However, association between OBS and MetS and its components has not been reported. Methods: This cross-sectional study included adult individuals with complete OBS and MetS data from National Health and Nutrition Examination Survey (NHANES) 2011-2018. A weighted logistic regression analysis was conducted to identify the association of the total, dietary, and lifestyle OBS scores with MetS. Subgroup analyses and restricted cubic splines were used to further explore associations. Results: In total, 10,025 eligible adult individuals (51.48% were males at a median age of 46 years) were included, with a MetS prevalence of 29.98%. In fully adjusted model, higher total OBS was associated with reduced risk of MetS (Q3 vs. Q1: odds ratio [OR] = 0.57, 95% confidence interval [CI], 0.46-0.71, p < 0.001; Q4 vs. Q1: OR = 0.42, 95% CI, 0.33-0.53, p < 0.001; P for trend <0.001). Significant differences were observed in the relationship between dietary OBS and lifestyle OBS and MetS risk (continuous dietary OBS: OR = 0.97, 95% CI, 0.96-0.98, p < 0.001; continuous lifestyle OBS: OR = 0.61, 95% CI, 0.58-0.64, p < 0.001), as well as negative relationship between total OBS and risk of five MetS components (all p < 0.05). Subgroup analysis showed marital status modified the negative association between OBS and MetS in subgroup analysis (P for interaction = 0.014). Moreover, a nonlinear correlation between OBS and MetS (including its components) was found, further elucidating associations (all p < 0.05). Restricted cubic splines demonstrated not obviously U-shape correlation between OBS and MetS components (elevated triglyceride and blood pressure). Conclusion: This study suggests a strong association between the OBS and MetS and its components. Our data indicated that a higher OBS score was correlated with a decreased risk of MetS and its components in a nonlinear manner. Hence, the OBS may serve as an effective marker for identifying individuals with MetS, with a higher score indicating a predominance of more antioxidants.

9.
Chem Sci ; 15(10): 3610-3615, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38455024

RESUMEN

We report herein the synthesis of highly enantiopure inherently chiral N3,O-calix[2]arene[2]triazines from enantioselective macrocyclization enabled by chiral phosphoric acid-catalyzed intramolecular nucleophilic aromatic substitution reaction. In contrast to documented examples, the inherent chirality of the acquired compounds arises from one heteroatom difference in the linking positions of heteracalix[4](het)arenes.

10.
Support Care Cancer ; 32(3): 207, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436749

RESUMEN

PURPOSE: Children with leukemia may experience a range of chemotherapy-related symptoms. Identifying subgroups and their distinct characteristics of symptoms may improve symptom management. We aimed to identify subgroups and their distinct characteristics of chemotherapy-related symptoms in children with leukemia. METHODS: A cross-sectional survey was conducted among 500 children with leukemia, who completed questionnaires that assessed their demographic and clinical characteristics, as well as the Memorial Symptom Assessment Scale. Latent profile analysis was conducted to identify subgroups of symptoms. Additionally, multiple regression analysis and network analysis were utilized to reveal the characteristics of each subgroup. RESULTS: Four subgroups were identified: "Profile 1: low symptom burden subgroup" (26.2%), "Profile 2: moderate symptom burden subgroup in transitional period" (14.8%), "Profile 3: moderate psychological symptom burden subgroup" (35.6%), and "Profile 4: high symptom burden subgroup" (23.4%). Multiple logistic regression analysis indicated that lower primary caregiver's education level, lower family monthly income, self-paid medical expenses, induction remission period, and consolidation enhancement period were associated with more severe symptoms of subgroups. Network analysis further revealed that nausea was the core symptom in Profiles 1 and 2, while the core symptom in Profile 3 was "I don't look like myself." Additionally, worrying was the core symptom in Profile 4. CONCLUSION: There exists heterogeneity in chemotherapy-related symptoms. Four subgroups and their corresponding characteristics of children with varying symptom severity were identified. Identifying these subgroups will facilitate personalized care, maximize intervention effectiveness, and alleviate symptom burden.


Asunto(s)
Leucemia , Niño , Humanos , Estudios Transversales , Leucemia/tratamiento farmacológico , Escolaridad , Renta , Náusea
11.
ACS Nano ; 18(11): 8038-8050, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38437220

RESUMEN

Liquid metal (LM) particles can serve as initiators, functional fillers, and cross-linkers for hydrogels. Herein, we show that cellulose nanocrystals (CNCs) stabilize LM particles in aqueous solutions, such as those used to produce hydrogels. The CNC-coated LM particles initiate free-radical polymerization to form poly(acrylic acid) (PAA) hydrogel with exceptional properties─stretchability ∼2000%, excellent toughness ∼1.8 MJ/m3, mechanical resilience, and efficient self-healing─relative to cross-linked PAA networks polymerized using conventional molecular initiators. FTIR spectroscopy, rheology, and mechanical measurements suggest that physical bonds between PAA and both Ga3+ and LM-CNC particles contribute to the excellent mechanical properties. The gels are used to sense a wide range of strains, such as those associated with human motion, via changes in resistance through the gel. The sensitivity at low strains enables monitoring subtle physiological signals, such as pulse. Without significantly compromising the toughness, soaking the gels in salt solution brings about high ionic conductivity (3.8 S/m), enabling them to detect touch via piezoionic principles; the anions in the gel have higher mobility than cations, resulting in significant charge separation (current ∼30 µA, ∼10 µA/cm2) through the gel in response to touch. These attractive properties are promising for wearable sensors, energy harvesters, and self-powered ionic touch panels.

12.
Nat Mater ; 23(1): 29-30, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38129576
13.
Crit Care ; 27(1): 490, 2023 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-38093296

RESUMEN

BACKGROUND: Sepsis is defined as a life-threatening syndrome caused by an unbalanced host response to infection. The role of interleukin (IL)-36 cytokines binding to the IL-36 receptor (IL-36R) in host response during sepsis remains unknown. METHODS: Serum IL-36 level was measured in 47 septic patients sampled on the day of intensive care unit (ICU) and emergency department admission, 21 non-septic ICU patient controls, and 21 healthy volunteers. In addition, the effects of IL-36R deletion on host inflammatory response in cecal ligation and puncture (CLP)-induced polymicrobial sepsis was determined. RESULTS: On the day of ICU and emergency department admission, the patients with sepsis showed a significant increase in serum IL-36 levels compared with ICU patient controls and healthy volunteers, and the serum IL-36 levels were related to the severity of sepsis. Non-survivors of septic patients displayed significantly lower serum IL-36 levels compared with survivors. A high serum IL-36 level in ICU and emergency department admission was associated with 28-day mortality, and IL-36 was found to be an independent predictor of 28-day mortality in septic patients by logistic regression analysis. Furthermore, IL-36R deletion increased lethality in CLP-induced polymicrobial sepsis. Septic mice with IL-36R deletion had higher bacterial load and demonstrated more severe multiple organ injury (including lung, liver, and kidney) as indicated by clinical chemistry and histopathology. Mechanistically, IL-36R ligands released upon lung damage activated IL-36R+lung fibroblasts thereby inducing expression of the antimicrobial protein lipocalin 2. Moreover, they induced the apoptosis of lung epithelial cells. CONCLUSIONS: Septic patients had elevated serum IL-36 levels, which may correlate with disease severity and mortality. In experimental sepsis, we demonstrated a previously unrecognized role of IL-36R deletion in increasing lethality.


Asunto(s)
Lesión Pulmonar , Sepsis , Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Células Epiteliales , Fibroblastos , Interleucinas
14.
Scand Cardiovasc J ; 57(1): 2286885, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38010775

RESUMEN

Objectives. Studies have shown that fasting blood glucose (FBG) is closely associated with poor prognosis in patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI), but its association with in-stent restenosis (ISR) is still unclear. Therefore, this study was to explore the association between FBG with ISR in patients with CHD after PCI. Design. In this cohort study, we included 531 patients with CHD who underwent PCI. Logistic regression, receiver operating characteristic (ROC), subgroup analysis and restricted cubic spline (RCS) were used to assess the association between FBG with ISR. Results. A total of 124 (23.4%) patients had ISR. Patients with higher levels of FBG had higher incidence of ISR compared to those with lower levels of FBG (p = 0.002). In multivariable logistic regression analyses, higher levels of FBG remained strongly associated with higher risk of ISR (as a categorical variable, OR: 1.89, 95% CI: 1.21-2.94, p = 0.005; as a continuous variable, OR: 1.12, 95% CI: 1.03-1.23, p = 0.011). ROC analysis also showed that FBG might be associated with the occurrence of ISR (AUC = 0.577, 95% CI: 0.52-0.64, p = 0.013). Subgroup analyses showed the association of FBG with ISR was also stable in several subgroups (< 60 years or ≥ 60 years, male, with or without smoking, without diabetes and without hypertension). And RCS analysis showed that FBG was linearly and positively associated with the risk of ISR. Conclusions. Higher levels of FBG were closely associated with higher risk of ISR in patients with CHD after PCI.


Asunto(s)
Reestenosis Coronaria , Intervención Coronaria Percutánea , Humanos , Masculino , Intervención Coronaria Percutánea/efectos adversos , Estudios de Cohortes , Glucemia , Reestenosis Coronaria/etiología , Constricción Patológica , Ayuno , Angiografía Coronaria/efectos adversos , Factores de Riesgo , Estudios Retrospectivos , Stents/efectos adversos
15.
Front Oncol ; 13: 1236129, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37671049

RESUMEN

Background: Previous studies have examined symptom clusters in children with acute leukemia, yet a knowledge gap persists regarding central symptom clusters and their influencing factors. By identifying these central clusters and associated factors, healthcare providers can enhance their understanding and effective management of symptoms. Our study seeks to address this gap by identifying symptom clusters, exploring central clusters, and investigating the demographic and health-related factors associated with these clusters in children with acute leukemia undergoing chemotherapy. Methods: A total of 586 children with acute leukemia from January 2021 to April 2023 were recruited from China. They were investigated using Memorial Symptom Assessment Scale 10-18 during chemotherapy. The principal component analysis was used to identify the symptom clusters. An association network was conducted to describe the relationships among symptoms and clusters. A multiple linear model was used to investigate the associated factors for the severity of overall symptoms and each symptom cluster. Results: Five clusters were identified, including oral and skin cluster, somatic cluster, self-image disorder cluster, gastrointestinal cluster and psychological cluster. Gastrointestinal cluster was the most central symptom cluster. Age, sex, clinical classification, number of having chemotherapy and education degree and marital status of the primary caregiver are associated with the severity of these five symptom clusters. Conclusion: Our study highlights the importance of evaluating symptom clusters in children with acute leukemia during chemotherapy. Specifically, addressing gastrointestinal symptoms is crucial for effective symptom management and overall care.

16.
Support Care Cancer ; 31(10): 578, 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37715817

RESUMEN

PURPOSE: Children with acute leukemia have suffered from a considerable symptom burden during chemotherapy. However, few studies have focused on exploring the mechanisms among symptoms in children with acute leukemia. Our study aims to explore core symptoms and describe the interrelationships among symptoms in children with acute leukemia during chemotherapy. METHODS: From January 2021 to March 2023, 469 children with acute leukemia were recruited from 20 Chinese cities. The Memorial Symptom Assessment Scale 10-18 (MSAS 10-18) was used to evaluate the prevalence and severity of symptoms during chemotherapy. A network analysis was performed by the R software based on 31 symptoms. Centrality indices and density were used to explore core symptoms and describe interrelationships among symptoms in the network during chemotherapy. RESULTS: Worrying and feeling irritable were the central symptoms across the three centrality indices, including strength, closeness, and betweenness. Lack of energy was the most prevalent symptom; however, it was less central than other symptoms. The density of the "induction and remission" network significantly differed from other cycles' counterparts (p < 0.001). Global strength was greater in the " ≥ 8 years group " network than the " < 8 years group " network (p = 0.023). CONCLUSION: Network analysis provides a novel approach to identifying the core symptoms and understanding the interrelationships among symptoms. Our study indicates the need to assess emotional symptoms in children with acute leukemia during chemotherapy, especially during the induction and remission phases, as well as in older children. Future research is imperative to construct trajectories of dynamic symptom networks and centrality indices in longitudinal data to investigate the causal relationships among symptoms.


Asunto(s)
Antineoplásicos , Leucemia , Niño , Humanos , Pueblo Asiatico , Emociones , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/epidemiología , Programas Informáticos , Antineoplásicos/uso terapéutico , Leucemia/diagnóstico , Leucemia/tratamiento farmacológico , Leucemia/psicología , Enfermedad Aguda , China
17.
Chem Sci ; 14(31): 8393-8400, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37564407

RESUMEN

In contrast to a plethora of macrocyclic and cage compounds, spirophanes have remained largely unexplored. We report herein the construction, structure and properties of unprecedented tetrahomo corona[4]arene-based ditopic and tritopic macrocycles of spiro structures. Synthesis was conveniently achieved by means of an efficient SNAr reaction from simple and commercially available starting materials. Racemic samples were resolved into enantiopure chiral tetrahomo i-corona[4]arenes, spirophanes and bispirophanes which show interesting chiroptical properties. The acquired electron-deficient macrocyclic compounds were found to adopt unique conformational structures and to form distinct complexes with TTF in the solid state. Our study provides a new opportunity to develop multitopic macrocycles of different topologies which have potential applications in supramolecular chemistry.

18.
Org Lett ; 25(27): 5105-5110, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37383012

RESUMEN

Despite their interesting stereochemistry and potential applications in (supramolecular) chemistry and chiroptical materials, inherently chiral macrocyclic compounds remain rare and are largely unexplored. We report herein a fragment coupling method to construct ABAC- and ABCD-type inherently chiral heteracalix[4]aromatics. The synthesis involves SNAr CuI-catalyzed Ullmann coupling and aliphatic nucleophilic substitution reactions as key steps using readily available starting materials. Postmacrocyclization functionalization reactions enabled the production of amino-substituted and (benzo[d])imidazole-2-(thi)one-bearing heteracalix[4]aromatics. Enantiopure ABCD-type macrocycles were obtained from resolution.


Asunto(s)
Compuestos Macrocíclicos , Estructura Molecular , Estereoisomerismo , Calixarenos/química
19.
Org Lett ; 25(21): 3936-3940, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37219082

RESUMEN

Asymmetric synthesis of enantioenriched zigzag-type molecular belts featuring copper/H8-binaphthol-catalyzed kinetic resolution of a resorcinarene derivative and subsequent transformations was developed. The acquired rigid and C4-symmetric belt exhibited remarkably enhanced photophysical and chiroptical properties in comparison to its conformationally fluxional macrocyclic precursor.

20.
Angew Chem Int Ed Engl ; 62(24): e202302646, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37088714

RESUMEN

Hydrocarbon belts have drawn great attention because of their unique structures and tantalizing properties. Although a few belts and heteroatom-doped analogs have been synthesized, belt molecules containing non-hexagonal rings remain rare. Herein we report the construction and application of unprecedented zigzag-type hydrocarbon belts which contain functionalized eight-membered rings. The synthesis features fourfold intramolecular acylation reactions of resorcin[4]arene-derived intermediates, which affords C4 -symmetric tetrabenzobelt[4]arene[4]cyclooctatrienones. Stereoselective ketone reduction with LiAlH4 and nucleophilic addition with alkynyllithiums provide the corresponding tetrahydroxylated belts. The tetraol and its methyl ether are powerful and selective hosts to form 2 : 1 and 1 : 1 complexes with cesium ion, respectively, with binding constants up to (1.71±0.33)×1011  M-2 and (1.50±0.16)×106  M-1 . In addition, enantiopure C4 -symmetric belts can emit CPL with |glum | being around 0.01.

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