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1.
Clin Case Rep ; 12(11): e9541, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39502127

RESUMEN

Prompt and precise diagnosis of pituitary hyperplasia secondary to primary hypothyroidism (PHPH) is crucial to avoid unwarranted pituitary surgery and potential permanent impairment. Although PHPH may present similarly to pituitary adenoma, it is responsive to thyroxine therapy, underscoring the critical role of differential diagnosis in the treatment of adolescent patients.

2.
Food Chem X ; 23: 101754, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39263339

RESUMEN

This study investigated the effects of incorporating different levels of Euglena gracilis microalgae powder (MP) on the dough properties, rheology, and quality attributes of Chinese steamed bread (CSB) for the first time. Moderate levels of MP (2%) reinforced the gluten network and improved protein structure, while higher levels (4-8%) adversely affected the gluten network and rheological properties. The addition of MP decreased the specific volume, pore number, and pore density of CSB, but increased pore size, hardness, and chewiness. It also imparted a yellow color to the CSB and slowed down moisture loss during storage. Notably, MP effectively increased the protein and lipid content of CSB, enhancing its nutritional value. The results suggest that optimizing the MP level is crucial to achieve nutritional enhancement while maintaining desirable texture and sensory attributes. An addition of 2% MP can strike a balance between nutrition and the overall quality of the final product.

3.
World J Diabetes ; 15(7): 1477-1488, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39099806

RESUMEN

BACKGROUND: The glycemic control of children with type 1 diabetes (T1D) may be influenced by the economic status of their parents. AIM: To investigate the association between parental economic status and blood glucose levels of children with T1D using a mobile health application. METHODS: Data from children with T1D in China's largest T1D online community, Tang-TangQuan®. Blood glucose levels were uploaded every three months and parental economic status was evaluated based on annual household income. Children were divided into three groups: Low-income (< 30000 Yuan), middle-income (30000-100000 Yuan), and high-income (> 100000 yuan) (1 Yuan = 0.145 United States Dollar approximately). Blood glucose levels were compared among the groups and associations were explored using Spearman's correlation analysis and multivariable logistic regression. RESULTS: From September 2015 to August 2022, 1406 eligible children with T1D were included (779 female, 55.4%). Median age was 8.1 years (Q1-Q3: 4.6-11.6) and duration of T1D was 0.06 years (0.02-0.44). Participants were divided into three groups: Low-income (n = 320), middle-income (n = 724), and high-income (n = 362). Baseline hemoglobin A1c (HbA1c) levels were comparable among the three groups (P = 0.072). However, at month 36, the low-income group had the highest HbA1c levels (P = 0.036). Within three years after registration, glucose levels increased significantly in the low-income group but not in the middle-income and high-income groups. Parental economic status was negatively correlated with pre-dinner glucose (r = -0.272, P = 0.012). After adjustment for confounders, parental economic status remained a significant factor related to pre-dinner glucose levels (odds ratio = 13.02, 95%CI: 1.99 to 126.05, P = 0.002). CONCLUSION: The blood glucose levels of children with T1D were negatively associated with parental economic status. It is suggested that parental economic status should be taken into consideration in the management of T1D for children.

4.
Foods ; 13(16)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39200426

RESUMEN

Light, as a crucial environmental determinant, profoundly influences the synthesis of secondary metabolites in plant metabolism. This study investigated the impacts of the red light combined with ultraviolet-A (UV-A) and ultraviolet-B (UV-B) treatments on phenolic acid biosynthesis in black wheat seedlings. The results demonstrate that the red light combined with UV-A and UV-B treatments significantly enhanced the levels of phenolic acids in black wheat seedlings, at 220.4 µg/seedling and 241.5 µg/seedling, respectively. The content of bound phenolic acids in black wheat seedlings increased by 36.0% under the UV-B treatment. The application of the UV-A/UV-B treatments markedly enhanced the activities of phenylalanine ammonia-lyase, 4-coumarate CoA ligase, and cinnamate 4-hydroxylase in black wheat seedlings while also promoting the expression levels of genes related to phenolic acid synthesis. The expression levels of fructose-1,6-bisphosphate aldolase and NADP-malic enzyme related to photosynthesis were significantly upregulated. This resulted in an augmentation in the chlorophyll content, thereby enhancing photosynthesis in black wheat seedlings. Nevertheless, the UV-A and UV-B treatments also had a significant constraining effect on the growth and development of black wheat seedlings. In addition, the UV-A and UV-B treatments increased the activity and gene expression levels of antioxidant enzymes while significantly increasing the contents of total flavonoids and anthocyanins, activating the antioxidant system. The findings reveal that light-source radiation serves as an effective method for promoting the biosynthesis of phenolic acids in black wheat seedlings.

5.
Angew Chem Int Ed Engl ; 63(43): e202411415, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-38990843

RESUMEN

The synthesis of fully fused π-conjugated cycloarenes embedded with nonbenzenoid aromatics is challenging. In this work, the first example of four-membered ring-embedded cycloarene (MF2) was designed and synthesized in single-crystal form by macrocyclization and ring fusion strategies. For comparison, single bond-linked chiral macrocycle MS2 without two fused four-membered rings and its linear-shaped polycyclic benzenoid monomer L1 were also synthesized. The pronounced anti-aromaticity of four-membered rings significantly adjusts the electronic structures and photophysical properties of cycloarene, resulting in an enhancement of the photoluminescence quantum yield (PLQY) from 10.66 % and 10.74 % for L1 and MS2, respectively, to 54.05 % for MF2, which is the highest PLQY among the reported cycloarenes. Notably, owing to the embedded anti-aromatic four-membered rings that reduce structural displacements, MF2 exhibits an ultra-narrowband emission with a single-digit full-width at half-maximum (FWHM) of only 7 nm (0.038 eV), which sets a new record among all reported organic narrowband luminescent molecules, and represents the first example of ultra-narrowband emission in conventional polycyclic aromatic hydrocarbons (PAHs) devoid of heteroatoms.

6.
Plant Sci ; 347: 112197, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39019089

RESUMEN

Isoflavone, which are mainly found in soybeans, are a secondary metabolite with a variety of physiological functions. In recent years, increasing the isoflavone content of soybeans has received widespread attention. Although ethephon treatment significantly increased isoflavone content in soybean sprouts, it also had a certain inhibitory effect on the growth of sprouts. Melatonin (MT), as a new type of plant hormone, not only alleviated the damage caused by abiotic stress to plants, but also promoted the synthesis of secondary metabolites. In this study, we aimed to elucidate the mechanism of exogenous MT in regulating the growth and development, and the metabolism of isoflavone in soybean sprouts under ethephon treatment. The results indicated that MT alleviated the adverse effects of ethephon treatment on soybean sprouts by increasing the activities of superoxide dismutase, peroxidase, catalase, and the expression of their corresponding genes, as well as decreased the content of malondialdehyde and hydrogen peroxide. In addition, MT further increased the isoflavone content by up-regulating the expression level of isoflavone synthesis genes and increased the activities of phenylalanine ammonia-lyase and cinnamic acid 4-hydroxylase under ethephon treatment. This study provided technical support and reference value for the production of high-quality soybean sprouts to a certain extent.


Asunto(s)
Antioxidantes , Etilenos , Glycine max , Isoflavonas , Melatonina , Reguladores del Crecimiento de las Plantas , Glycine max/metabolismo , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Glycine max/genética , Melatonina/metabolismo , Isoflavonas/metabolismo , Isoflavonas/biosíntesis , Etilenos/metabolismo , Antioxidantes/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Plantones/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Compuestos Organofosforados/farmacología , Compuestos Organofosforados/metabolismo
7.
J Am Chem Soc ; 146(31): 21922-21931, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39052980

RESUMEN

Donor-acceptor (D-A) conjugated systems have been extensively investigated and play important roles in organic electronics. Incorporating D-A structures into (hetero)cycloarenes endows them tunable electronic properties, while the well-defined cavity remains. However, the synthetic complexity of introducing electron-acceptor moieties into (hetero)cycloarenes limits their development and applications. In this paper, the first family of electronically tunable D-A heterocycloarenes (DAHCn, n = 1-5) based on pyrazine derivatives was facilely synthesized through cyclocondensation reaction from a tetraketone-functionalized heterocycloarene precursor prepared using the ketal-protection strategy. The effect of expanded conjugation and the inserted electron-withdrawing group on the electronic structures of the D-A heterocycloarenes was studied systematically by X-ray crystallographic analysis, various spectroscopic measurements, and theoretical calculations. Interestingly, the presence of an electron-withdrawing group polarizes the inner C(sp2)-H and significantly increases the binding affinities of D-A heterocycloarenes to the iodide anion. Meanwhile, the anion affinity can be further modulated by the type of attached substituents and the distance of polarization. More importantly, the dicyanopyrazine derivative DAHC3 shows the highest binding strength to the iodide ion as a 2:1 sandwich complex (log ß2 = 12.3 and ΔG = -69.1 kJ mol-1), which is the strongest iodide receptor using C(sp2)-H hydrogen bonding interactions reported to date. Our finding provides a new strategy to design and synthesize D-A heterocycloarenes and strong anion receptors.

8.
Front Nutr ; 11: 1403293, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38899320

RESUMEN

Phenolic acids are secondary metabolites in higher plants, with antioxidant, anticancer, and anti-aging effects on the human body. Therefore, foods rich in phenolic acids are popular. Methyl jasmonate (MeJA) promoted phenolic acids accumulation but also inhibited sprout growth. Melatonin (MT) was a new type of plant hormone that not only alleviated plants' abiotic stress, but also promoted the synthesis of plant-stimulating metabolism. This study aimed to elucidate the mechanism of exogenous MT on the growth and development, and phenolic acids metabolism of barley sprouts under MeJA treatment. The results showed that MT increased the phenolic acids content in sprouts by increasing the activities of phenylalanine ammonia-lyase and cinnamic acid 4-hydroxylase, and up-regulating the gene expression of phenylalanine ammonia-lyase, cinnamic acid 4-hydroxylase, 4-coumarate: coenzyme a ligase, and ferulic acid-5-hydroxylase. MT attenuated the growth inhibition of barley sprouts under MeJA stress by increasing the activities of regulated antioxidant enzymes and the expression of their corresponding genes. Furthermore, MT increased the NO content and induced Ca2+ burst in barley sprouts under MeJA stress. These events were inhibited by DL-4-Chlorophenylalanine. These results suggested that MT ameliorated growth inhibition and promoted the biosynthesis of phenolic acids in barley sprouts under MeJA stress.

9.
Org Lett ; 26(23): 5010-5015, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38819192

RESUMEN

Two fully fused acceptor-donor-acceptor (A-D-A) architecture conjugated derivatives (NPF and NCF) comprising an electron-withdrawing naphthalimide (NMI) and two different electron-donating cores, phenanthrene and carbazole, respectively, were conveniently synthesized by bismuth(III)-catalyzed selective cyclization of vinyl ethers. Compared with their corresponding single bond-linked A-D-A molecules NPS and NCS, both having a moderately twisted aromatic configuration, the ring fusion strategy leads to fully coplanar conjugated skeletons and greatly changes the electronic structures, photophysical properties, self-assembling behaviors, and molecular packing motifs. In particular, the naphthalimide/carbazole derivative NCF exhibits intriguing 2D brickwork packing and significantly enhanced self-assembling properties.

10.
Food Chem ; 450: 139360, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-38640528

RESUMEN

As the world's population and income levels continue to rise, there is a substantial increase in the demand for meat, which poses significant environmental challenges due to large-scale livestock production. This review explores the potential of microalgae as a sustainable protein source for meat analogues. The nutritional composition, functional properties, and environmental advantages of microalgae are analyzed. Additionally, current obstacles to large-scale microalgal food production are addressed, such as strain development, contamination risks, water usage, and downstream processing. The challenges associated with creating meat-like textures and flavors using techniques like extrusion and emulsion formation with microalgae are also examined. Lastly, considerations related to consumer acceptance, marketing, and regulation are summarized. By focusing on improvements in cultivation, structure, sensory attributes, and affordability, microalgae demonstrate promise as a transformative and eco-friendly protein source to enhance the next generation of meat alternatives.


Asunto(s)
Carne , Microalgas , Microalgas/química , Microalgas/metabolismo , Microalgas/crecimiento & desarrollo , Animales , Humanos , Carne/análisis , Valor Nutritivo , Sustitutos de la Carne
11.
Foods ; 13(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38540858

RESUMEN

Exogenous abiotic stimulant treatments are a straightforward and effective method for enhancing secondary metabolites in plants. In this study, the response surface optimization method was used to optimize the conditions for enriching flavonoids in short-germinated black soybeans under a slight acid treatment, and the mechanism of flavonoid accumulation during black soybean germination was explored. The results show that the use of a 126.2 mM citric acid-sodium citrate buffer (pH 5.10) as a slight acid treatment resulted in the highest flavonoid content when the black soybeans were germinated for 24 h. Under these conditions, the isoflavonoid (glycitin, daidzein, and genistein) increased significantly, and the flavonoid content reached 2.32 mg/g FW. The microacidified germination treatment significantly increased the activities and relative gene expression levels of key enzymes involved in flavonoid metabolism (4-coumarate-CoA ligase and cinnamic acid 4-hydroxylase, etc.). However, the slight acid treatment inhibited the growth of the black soybeans and caused damage to their cells. This was evidenced by significantly higher levels of malondialdehyde, superoxide anion, and hydrogen peroxide compared to the control group. Furthermore, the antioxidant system in the short-germinated soybeans was activated by the slight acid treatment, leading to a significant increase in the activities and relative gene expression levels of catalase and peroxidase. The results above show that a slight acid treatment was beneficial in inducing the accumulation of flavonoids during the growth of black soybean sprouts. This lays a technical foundation for producing black soybean products that are rich in flavonoids.

12.
Chem Sci ; 15(12): 4590-4601, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38516086

RESUMEN

π-Conjugated macrocycles have been highly attractive due to their challenging synthesis, fascinating aesthetic structure and unique physical and chemical properties. Although some progress has been made in synthesis, the study of π-macrocycles with different structural characteristics and supramolecular interactions still faces major challenges. In this paper, two new single-bond linked macrocycles (MS-4T/MS-6T) were reported, and the corresponding vinyl-bridged heterocycloarenes (MF-4T/MF-6T) were synthesized by the periphery fusion strategy. Further studies have indicated that the structure of these four macrocycles is determined by both size and curvature, showing unique variations from nearly planar to bowl and then to saddle. Interestingly, the nearly planar MS-4T with a small size and the rigid saddle-shaped MF-6T show no obvious response to fullerenes C60 or C70, while the bowl-shaped MS-6T and MF-4T demonstrate a strong binding affinity towards fullerenes C60 and C70. What's more, two kinds of co-crystals with capsule-like configurations, MS-6T@C60 and MS-6T@C70, have been successfully obtained, among which the former shows a loose columnar arrangement while the latter displays a unique three-dimensional honeycomb arrangement that is extremely rare in supramolecular complexes. This work systematically studies the π-conjugated macrocycles and provides a new idea for the development of novel host-guest systems and further multifunctional applications.

13.
J Sci Food Agric ; 104(9): 5350-5359, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38329450

RESUMEN

BACKGROUND: Phenolic acid exhibits a variety of well-known physiological functions. In this study, optimal germination conditions to ensure total phenolic acid enrichment in barley sprouts induced by salicylic acid treatment and its effects on sprout physiology and activity, as well as the gene expression of key enzymes for phenolic acid biosynthesis, were investigated. RESULTS: When sprouts were treated with 1 mmol L-1 salicylic acid during germination and germinated at 25 °C for 4 days, the phenolic acid content was 1.82 times that of the control, reaching 1221.54 µg g-1 fresh weight. Salicylic acid significantly increased the activity of phenylalanine aminolase and cinnamic acid-4-hydroxylase and the gene expression of phenylalanine aminolase, cinnamic acid-3-hydroxylase, cinnamic acid-4-hydroxylase, 4-coumaric acid-coenzyme A, caffeic acid O-methyltransferase, and ferulate-5-hydroxylase in barley sprouts. However, salicylic acid treatment significantly increased malondialdehyde and H2O2 content, H2O2 and O2 - fluorescence intensity, as well as significantly decreasing sprout length and fresh weight. Salicylic acid treatment markedly increased the activity of peroxidase and catalase and the gene expression of peroxidase, catalase, and ascorbate peroxidase in barley sprouts. CONCLUSION: Salicylic acid treatment during barley germination significantly promoted the enrichment of total phenolic acid by increasing the activities and gene expression levels of enzymes involved in the phenolic acid biosynthesis pathway. Salicylic acid induced the accumulation of reactive oxygen species, inhibited sprout growth, and activated the antioxidant system. This study provides a basis for the future development of functional foods using phenol acid-rich plants as raw materials. © 2024 Society of Chemical Industry.


Asunto(s)
Germinación , Hordeum , Hidroxibenzoatos , Proteínas de Plantas , Ácido Salicílico , Hordeum/crecimiento & desarrollo , Hordeum/metabolismo , Hordeum/efectos de los fármacos , Hordeum/genética , Ácido Salicílico/farmacología , Ácido Salicílico/metabolismo , Hidroxibenzoatos/metabolismo , Germinación/efectos de los fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Plantones/efectos de los fármacos , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Semillas/efectos de los fármacos , Semillas/química , Peróxido de Hidrógeno/metabolismo , Catalasa/metabolismo , Catalasa/genética
14.
Food Chem X ; 21: 101181, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38357373

RESUMEN

The massive production of food waste and plastic pollution necessitates innovative solutions. This study reports the first fabrication of a flexible chitosan (CH) film reinforced with lignosulfonate (LS) derived from pulping byproduct as a sustainable alternative to synthetic food packaging. The CH/LS composite film was prepared by a simple casting method with varying LS contents of 1 % and 2 %. Compared to CH film, the addition of 2 % LS increased the tensile strength by over 4 times and decreased water vapor permeability by 11 %. Moreover, the CH/LS film exhibited excellent UV-shielding properties. This novel use of LS to reinforce CH film presents an eco-friendly active packaging material. When used to package cherry tomatoes for 2 weeks, the CH/LS film effectively maintained fruit freshness and hardness while minimizing weight loss. This work provides new scientific evidence on the optimized preparation and application of CH/LS composite films from renewable resources for food preservation.

15.
Sci Total Environ ; 896: 165200, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37400020

RESUMEN

Microalgae have been recognized as emerging cell factories due to the high value-added bio-products. However, the balance between algal growth and the accumulation of metabolites is always the main contradiction in algal biomass production. Hence, the security and effectiveness of regulating microalgal growth and metabolism simultaneously have drawn substantial attention. Since the correspondence between microalgal growth and reactive oxygen species (ROS) level has been confirmed, improving its growth under oxidative stress and promoting biomass accumulation under non-oxidative stress by exogenous mitigators is feasible. This paper first introduced ROS generation in microalgae and described the effects of different abiotic stresses on the physiological and biochemical status of microalgae from these aspects associated with growth, cell morphology and structure, and antioxidant system. Secondly, the role of exogenous mitigators with different mechanisms in alleviating abiotic stress was concluded. Finally, the possibility of exogenous antioxidants regulating microalgal growth and improving the accumulation of specific products under non-stress conditions was discussed.


Asunto(s)
Microalgas , Especies Reactivas de Oxígeno/metabolismo , Microalgas/metabolismo , Biomasa , Estrés Oxidativo , Estrés Fisiológico , Antioxidantes/metabolismo , Biocombustibles
16.
Chem Sci ; 14(22): 6087-6094, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37293645

RESUMEN

The precise synthesis of cycloarenes remains a challenging topic in both organic chemistry and materials science due to their unique fully fused macrocyclic π-conjugated structure. Herein, a series of alkoxyl- and aryl-cosubstituted cycloarenes (kekulene and edge-extended kekulene derivatives, K1-K3) were conveniently synthesized and an unexpected transformation of the anthryl-containing cycloarene K3 into a carbonylated cycloarene derivative K3-R was disclosed by controlling the temperature and gas atmosphere of the Bi(OTf)3-catalyzed cyclization reaction. All their molecular structures were confirmed by single-crystal X-ray analysis. The crystallographic data, NMR measurements, and theoretical calculations reveal their rigid quasi-planar skeletons, dominant local aromaticities, and decreasing intermolecular π-π stacking distance with extension of the two opposite edges. The much lower oxidation potential for K3 by cyclic voltammetry explains its unique reactivity. Moreover, carbonylated cycloarene derivative K3-R shows a remarkable stability, large diradical character, a small singlet-triplet energy gap (ΔES-T = -1.81 kcal mol-1), and weak intramolecular spin-spin coupling. Most importantly, it represents the first example of carbonylated cycloarene diradicaloids as well as the first example of radical-acceptor cycloarenes and will shed some light on synthesis of extended kekulenes and conjugated macrocyclic diradicaloids and polyradicaloids.

17.
Food Chem ; 426: 136603, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37329791

RESUMEN

Broccoli sprouts have a strong ability to accumulate isothiocyanate and selenium. In this study, the isothiocyanate content increased significantly as a result of ZnSO4 stress. Particularly, based on the isothiocyanate content is not affected, the combined ZnSO4 and Na2SeO3 treatment alleviated the inhibition of ZnSO4 and induced selenium content. Gene transcription and protein expression analyses revealed the changes in isothiocyanate and selenium metabolite levels in broccoli sprouts. ZnSO4 combined with Na2SeO3 was proven to activate a series of isothiocyanate metabolite genes (UGT74B1, OX1, and ST5b) and selenium metabolite genes (BoSultr1;1, BoCOQ5-2, and BoHMT1). The relative abundance of the total 317 and 203 proteins, respectively, in 4-day-old broccoli sprouts varied, and the metabolic and biosynthetic pathways for secondary metabolites were significantly enriched in ZnSO4/control and ZnSO4 combined Na2SeO3/ZnSO4 comparisons. The findings demonstrated how ZnSO4 combined with Na2SeO3 treatment reduced stress inhibition and the accumulation of encouraged selenium and isothiocyanates during the growth of broccoli sprouts.


Asunto(s)
Brassica , Selenio , Selenio/metabolismo , Proteoma/metabolismo , Isotiocianatos/metabolismo , Azufre , Brassica/metabolismo , Glucosinolatos/metabolismo , Sulfóxidos/metabolismo
18.
Adv Mater ; 35(20): e2300094, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36807375

RESUMEN

Designing (hetero)cycloarenes through the modifications of the π-topology and molecular packing of organic semiconductors has recently garnered considerable attention. However, their applications as an organic active layer in field-effect transistors are very limited, and the obtained hole carrier mobilities are less than 1 cm2 V-1 s-1 . In this work, a novel alkyl-substituted coplanar N-heterocycloarene (FM-C4) containing four carbazole units is successfully synthesized in crystalline form. As compared to the corresponding single-bond-linked carbazole-based macrocycle M-C4, it is found that the periphery fusion strategy greatly changes the electronic structures, energy levels, photophysical properties, host-guest interactions with fullerenes, and molecular crystal stacking motifs. In particular, the fully fused N-heterocycloarene FM-C4 exhibits a herringbone packing structure with an unusual long-range π-π overlap distance as low as 3.19 Å, whereas the single crystal of M-C4 demonstrates no π-π interactions. As a consequence, FM-C4 in single-crystal transistors displays the highest hole mobility of 2.06 cm2 V-1 s-1 , significantly outperforming M-C4 and all the reported (hetero)cycloarenes and suggesting the high potential of (hetero)cycloarenes for organic electronic applications.

20.
J Am Chem Soc ; 144(47): 21521-21529, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36343157

RESUMEN

Cycloarenes and heterocycloarenes display unique physical structures and hold great potential as organic semiconductors. However, the synthesis of (hetero)cycloarenes remains a big challenge, and there are limited reports on their applications. Herein, a series of nitrogen- and sulfur-codoped cycloarenes NS-Octulene-n (n = 2, 3, 4) with branched alkyl substituents containing linear spacer groups from C2 to C4 have been conveniently synthesized. Compared with their isoelectronic analogues Octulene and S-Octulene, both having a saddle-shaped configuration, the coincorporation of two nitrogen atoms and two sulfur atoms leads to a fully coplanar aromatic backbone structure. Each of these three planar heterocycloarenes acts as a supramolecular host for encapsulation of both fullerenes C60 and C70 with a stronger donor-acceptor interaction for the complexation between the heterocycloarene and C70 due to the unique molecular geometry and defined cavity. Meanwhile, the electron-rich nitrogen atoms also slightly increase the energies of both highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in this series of planar heterocycloarenes, indicating that they can be used as p-type semiconductors. Most importantly, benefitting from the planar π-conjugated backbone structure accompanied by excellent crystallinity and ordered molecular packing, as well as upon the engineering of the alkyl chain branching position, thin-film field-effect transistors of NS-Octulene-3 with moderate alkyl branching point exhibit the maximum hole mobility of 0.86 cm2 V-1 s-1, which is the highest for (hetero)cycloarene-based organic semiconductors. This study will shed new light on designing novel high-performance macrocyclic polycyclic aromatic hydrocarbon (PAH) semiconductors.

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