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1.
Nat Commun ; 15(1): 4371, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778032

ABSTRACT

A protocol for trans-hydroboration of indole derivatives using heterogeneous photocatalysis with NHC-borane has been developed, addressing a persistent challenge in organic synthesis. The protocol, leveraging high crystalline vacancy-engineered polymeric carbon nitride as a catalyst, enables diastereoselective synthesis, expanding substrate scope and complementing existing methods. The approach emphasizes eco-friendliness, cost-effectiveness, and scalability, making it suitable for industrial applications, particularly in renewable energy contexts. The catalyst's superior performance, attributed to its rich carbon-vacancies and well-ordered structure, surpasses more expensive homogeneous alternatives, enhancing viability for large-scale use. This innovation holds promise for synthesizing bioactive compounds and materials relevant to medicinal chemistry and beyond.

2.
J Fish Biol ; 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38476052

ABSTRACT

Senegalese sole, Solea senegalensis, is a flatfish of high commercial value in the world. It has been identified as an interesting and promising species for marine commercial aquaculture diversification in Europe for at least four decades and was introduced to China in 2003. Early ontogenesis from embryo to juvenile stages in S. senegalensis was analysed under controlled laboratory conditions to provide morphological information for aquaculture. From 0 to 59 days post hatching (dph), 10-20 larvae were sampled and measured each day (0-17 dph) or every 2-6 days (17-59 dph). Morphological characteristics from the egg to the juvenile stage were described. The eggs were separate and spherical with multiple oil globules. After 3 dph, the yolk sac was completely absorbed, mouth and anus were open, a swim bladder appeared, and larvae began feeding on rotifers (Brachionus plicatilis). The larvae began metamorphosis as the notochord flexed upward and the left eye migrated upward after 10 dph. The left eye migrated to the dorsal midline at 15 dph. At 19 dph, the left eye was translocated to the right-ocular side, and the juveniles adopted a benthic lifestyle. The swim bladder degenerated, and the juveniles completed metamorphosis at 23 dph. The growth patterns of some parameters (TL, SL, BH, BW) during larval and juvenile development stages were identified. The inflection points, which are slopes of growth changes, were calculated in growth curves. Three inflection points occurring in the growth curves of larvae and juveniles were found to be associated with metamorphosis, weaning, and transitions in feeding habits. The basic information of embryo development and ontogenesis in this study represents a valuable contribution to the S. senegalensis industry, especially in artificial breeding and rearing techniques.

3.
Org Lett ; 26(1): 310-314, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38134354

ABSTRACT

A feasible and effective method to synthesize α-fluoroalkenyl alcohols was reported. With the cooperation of photoredox and hydrogen atom transfer (HAT) processes, defluoroalkylations of gem-difluoroalkenes occurred smoothly with alcohols under visible-light irradiation. Notably, the protocols feature broad scopes, mild conditions, and validity for the late-stage functionalization of bioactive molecule derivatives. Mechanistic studies suggested that the reaction occurred through the radical coupling of the alkyl radical and the fluoroalkenyl radical.

4.
Animals (Basel) ; 13(21)2023 Nov 04.
Article in English | MEDLINE | ID: mdl-37958175

ABSTRACT

BACKGROUND: We investigated the growth and feeding characteristics of threadsail filefish, Stephanolepis cirrhifer, during early ontogenesis. METHODS: The growth indices of hatchlings fed compound feed were measured from 0 to 50 days post hatching (dph). The absorption time of the yolk sac and oil globule, as well as the rate of first feeding were measured to characterise the early growth stage and determine the point-of-no-return (PNR). Feeding characteristics and rhythms were investigated under a light/dark cycle and under continuous light. RESULTS: Growth indices increased significantly at 24, 28, 30, 40, 45, and 50 dph. The yolk sac and oil globules were completely absorbed before 4 dph, indicative of a short mixed-nutrition period at 3-4 dph. Under starvation conditions, the first feeding rate was highest (86%) at 0.5 dph and then decreased to 53.3% at 1.5 dph and 26.2% at 2 dph, suggesting that the PNR occurs at 1.5-2 dph. The feeding peak appeared at 15:00-18:00 and under light conditions, while the feeding trough appeared at 0:00-3:00. CONCLUSIONS: Compound feed supplied adequate nutrition for early growth and development. The peaks and troughs of feeding times were indicative of daytime feeding behaviour. These results provide guidance for successful rearing of filefish seedlings and juveniles.

5.
Cells ; 12(22)2023 11 16.
Article in English | MEDLINE | ID: mdl-37998369

ABSTRACT

(1) Fshß and Lhß showed stronger signals and higher transcript levels from 590 to 1050 dph than at earlier stages, implying their active involvement during primary oocyte development. (2) Fshß and Lhß at lower levels were detected during the phases of ovarian differentiation and oogonial proliferation. (3) E2 concentrations increased significantly at 174, 333, and 1435 dph, while T concentrations exhibited significant increases at 174 and 333 dph. These findings suggest potential correlations between serum E2 concentrations and the phases of oogonial proliferation and pre-vitellogenesis.


Subject(s)
Bass , Female , Animals , Bass/metabolism , Sex Differentiation , Gonadotropin-Releasing Hormone , Gonadal Steroid Hormones , Follicle Stimulating Hormone, beta Subunit/genetics , Luteinizing Hormone, beta Subunit , Brain/metabolism
6.
Angew Chem Int Ed Engl ; 62(36): e202304699, 2023 Sep 04.
Article in English | MEDLINE | ID: mdl-37409373

ABSTRACT

Developing new reactive pathway to activate inert C(sp3 )-H bonds for valuable oxygenated products remains a challenge. We prepared a series of triazine conjugated organic polymers to photoactivate C-H into aldehyde/ketone via O2 →H2 O2 →⋅OH→Cl⋅→Cl2 ⋅- . Experiment results showed Cl2 ⋅- could successively activate C(sp3 )-H more effectively than Cl⋅ to generate unstable dichlorinated intermediates, increasing the kinetic rate ratio of dichlorination to monochlorination by a factor of 2,000 and thus breaking traditional dichlorination kinetic constraints. These active intermediates were hydrolyzed into aldehydes or ketones easily, when compared with typical stable dichlorinated complexes, avoiding chlorinated by-product generation. Moreover, an integrated two-phase system in an acid solution strengthened the Cl2 ⋅- mediated process and inhibited product overoxidation, where the conversion rate of toluene reached 16.94 mmol/g/h and the selectivity of benzaldehyde was 99.5 %. This work presents a facile and efficient approach for selective conversion of inert C(sp3 )-H bonds using Cl2 ⋅- .

7.
Animals (Basel) ; 13(13)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37443845

ABSTRACT

The light spectrum is a key environmental cue involved in growth and reproduction in teleosts. This study investigated the effects of exposure on juvenile red spotted grouper exposed to white (control), red (590 nm), blue (480 nm), and green (520 nm) light-emitting diodes (LEDs) (12 h light:12 h dark) for two months. The body weight (BW), total length (TL), condition factor (CF), weight gain rate (WGR), gonadosomatic index (GSI), and hepatosomatic index (HSI) were assessed. Gonadal development was observed. The gene expression of growth-related hormones, such as growth hormone (GH), pre-pro-somatostatin-I (PSS-I), neuropeptide Y (NPY), and CCK, and of reproduction-related hormones, such as Kiss1, Kiss2, GPR54, sbGnRH, FSHß, and LHß, was analyzed. The results showed that the fish in the white LED group exhibited the best BW, TL, CF, WGR, and HSI after one or two months. The fish exposed to white LEDs showed the best growth after two months, but no significant differences in GH levels were detected. Contrarily, the expression levels of the PSS-I significantly increased (p < 0.05) in fish from the white group, suggesting the complex regulation of GH production and the limited effects of PSS-I on the inhibition of GH synthesis and somatic growth. The significantly increased NPY levels in the four LED groups (p < 0.05) indicated that these four LED spectra were effective in stimulating food intake and energy homeostasis. After two months, the gonads developed from chromatin nucleolar-stage oocytes to perinucleolar-stage oocytes in the four LED groups. The gene expression of Kiss2 and GPR54 in the four LED groups and of sbGnRH in the white and blue LED groups significantly increased when compared to that in the initial group (p < 0.05), while there were no significant differences in FSHß and LHß expression in the four LED groups. These results suggest that FSH and LH may not play important roles in gonadal development in juvenile red spotted grouper that are exposed to these four LED spectra.

8.
Org Lett ; 25(24): 4556-4561, 2023 Jun 23.
Article in English | MEDLINE | ID: mdl-37310027

ABSTRACT

Direct and selective fluoroarylations of nucleophilic secondary alkylanilines with polyfluoroarenes were first realized through visible-light-induced C-H/C-F couplings with the assistance of bases. Varieties of α-polyfluoroarylanilines were selectively produced with this protocol from polyfluoroarenes and N-alkylanilines, including natural products and pharmaceutical molecule derivatives. Mechanistic studies illustrated base-promoted photochemical C-H cleavage of the α-C-H bonds of alkylanilines to produce the N-α-carbon radical and then radical addition to polyfluoroarenes.


Subject(s)
Aniline Compounds , Light , Aniline Compounds/chemistry , Catalysis , Molecular Structure , Carbon/chemistry
9.
Nat Chem ; 15(5): 666-676, 2023 May.
Article in English | MEDLINE | ID: mdl-36894703

ABSTRACT

Organosilanes are of vital importance for modern human society, having found widespread applications in functional materials, organic synthesis, drug discovery and life sciences. However, their preparation remains far from trivial, and on-demand synthesis of heteroleptic substituted silicon reagents is a formidable challenge. The generation of silyl radicals from hydrosilanes via direct hydrogen-atom-transfer (HAT) photocatalysis represents the most atom-, step-, redox- and catalyst-economic pathway for the activation of hydrosilanes. Here, in view of the green characteristics of neutral eosin Y (such as its abundance, low cost, metal-free nature, absorption of visible light and excellent selectivity), we show that using it as a direct HAT photocatalyst enables the stepwise custom functionalization of multihydrosilanes, giving access to fully substituted silicon compounds. By exploiting this strategy, we realize preferable hydrogen abstraction of Si-H bonds in the presence of active C-H bonds, diverse functionalization of hydrosilanes (for example, alkylation, vinylation, allylation, arylation, deuteration, oxidation and halogenation), and remarkably selective monofunctionalization of di- and trihydrosilanes.

10.
Chem Sci ; 14(4): 916-922, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36755709

ABSTRACT

To provide α-polyfluoroarylalcohols, a novel protocol for the selective defluoroalkylation of polyfluoroarenes with easily accessible alcohols was reported via the cooperation of photoredox and hydrogen atom transfer (HAT) strategies with the assistance of Lewis acids under visible light irradiation. The protocol featured broad scope, excellent regioselectivity for both C-H and C-F bond cleavages, and mild conditions. Mechanistic studies suggested that the reaction occurred through Lewis acid-promoted HAT to provide an alkyl radical and sequential addition to polyfluoroarenes. Impressively, the regioselectivity for C-F cleavage was verified with the Fukui function. The feasibility and application of this protocol on fluoroarene synthesis were well illustrated by gram-scale synthesis under both batch and flow conditions, late-stage decoration of bioactive compounds, and further transformations of the fluoroarylalcohols.

11.
Article in English | MEDLINE | ID: mdl-36269926

ABSTRACT

Most current data-driven prognosis approaches suffer from their uncontrollable and unexplainable properties. To address this issue, this article proposes a physics-constraint variational neural network (PCVNN) for wear state assessment of the external gear pump. First, a response model of the pressure pulsation of the gear pump is constructed via a spectral method, and a compound neural network is utilized to extract features from the pressure pulsation signal. Then, the response model is formulated into an objective function to softly constrain the learning process of the neural network, forcing the learned features to have explicit physics meaning. Meanwhile, to characterize the system uncertainty, the variational inference is utilized to extend a Kullback-Leibler ( KL) divergence into the objective function. Finally, the wear state is evaluated based on the distance of learned physics features. Experimental results on an external gear pump validate the merits of the proposed method in explainable representation learning and system uncertainty estimation. It also offers a controllable and explainable perspective to understand the dynamic behavior of the system.

12.
Animals (Basel) ; 12(16)2022 Aug 13.
Article in English | MEDLINE | ID: mdl-36009652

ABSTRACT

Noise has the potential to induce physiological stress in marine fishes, which may lead to all sorts of ecological consequences. In the current study, we used the RNA-sequencing (RNA-seq) method to sequence the whole transcriptome of the brain in small yellow croaker (Larimichthys polyactis). The animals were exposed to a mix of noises produced by different types of boat played back in a tank, then the brain tissues were collected after the fish had been exposed to a 120 dB noise for 0.5 h. In total, 762 differently expressed genes (DEGs) between the two groups were identified, including 157 up regulated and 605 down regulated genes in the noise exposure group compared with the control group. Gene ontology (GO) enrichment analysis indicated that the most up regulated gene categories included synaptic membranes, receptor-mediated endocytosis and the neurotransmitter secretion process. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways found that endocytosis, cell adhesion molecules and the extracellular matrix (ECM) receptor interaction pathway were over-represented. Specifically, ECM-related genes, including lamin2, lamin3, lamin4, coll1a2, coll5a1 and col4a5 were down regulated in the noise exposure group, implying the impaired composition of the ECM. In addition, the behavioral experiment revealed that L. polyactis exhibited avoidance behaviors to run away from the noise source at the beginning of the noise exposure period. At the end of the noise exposure period, L. polyactis kept motionless on the surface of the water and lost the ability to keep their balance. Taken together, our results indicate that exposure to noise stress contributes to neurological dysfunction in the brain and impaired locomotor ability in L. polyactis.

13.
J Org Chem ; 87(16): 10807-10814, 2022 08 19.
Article in English | MEDLINE | ID: mdl-35921192

ABSTRACT

An expeditious construction of an unsymmetrical tertiary 9-fluorenol skeleton was accomplished starting from readily available α-ketoester and aryl iodide. Inexpensive commercially available substituted aniline was utilized as a potent monodentate transient directing group (TDG) to assist palladium-catalyzed direct ortho-C-H arylation and tandem dual C-H activation of α-ketoesters to form two carbon-carbon bonds. To demonstrate practical applications, the reaction was enlarged to the gram scale, and subsequent one-step derivatization allowed facile access to structurally diversified useful derivatives. A series of control experiments were carried out to shed light on the possible catalytic mechanism.


Subject(s)
Carbon , Palladium , Carbon/chemistry , Catalysis , Molecular Structure , Palladium/chemistry
14.
Cells ; 11(5)2022 02 27.
Article in English | MEDLINE | ID: mdl-35269447

ABSTRACT

Groupers are widely distributed in tropical and subtropical areas worldwide, are key species to coastal ecosystems, and valuable fishery targets. To facilitate artificial seed production technology for grouper aquaculture, the mechanisms of reproduction and gonad development are being elucidated for these important species. In addition, since groupers are sexually dimorphic fish with female-first maturity (protogynous hermaphrodite fish), research is being conducted to clarify the ecological mechanism of sex change and their reproductive physiology, focusing on the endocrine system. In recent years, research on groupers has also been conducted to understand changes in the coastal environment caused by ocean warming and man-made chemicals. However, due to difficulties associated with conducting research using wild populations for breeding experiments, knowledge of the physiology and ecology of these fish is lacking, especially their reproductive physiology. In this review, we present information on the reproductive physiology and endocrinology of groupers obtained to date, together with the characteristics of their life history.


Subject(s)
Ecosystem , Sex Determination Processes , Animals , Female , Fishes/physiology , Gonads , Humans , Reproduction/physiology , Sex Differentiation
15.
World J Clin Cases ; 9(29): 8694-8701, 2021 Oct 16.
Article in English | MEDLINE | ID: mdl-34734047

ABSTRACT

BACKGROUND: Respiratory tract infections in the elderly are difficult to cure and can easily recur, thereby posing a great threat to patient prognosis and quality of life. AIM: To investigate the therapeutic effects of different antibiotics in elderly patients with respiratory tract infection. METHODS: Seventy-four elderly patients with respiratory tract infection were randomly allocated to a study (n = 37; treated with cefoperazone sodium/sulbactam sodium) or control (n = 37; treated with piperacillin sodium/tazobactam sodium on the basis of routine symptomatic support) group. Both groups were treated for 7 d. Time to symptom relief (leukocyte recovery; body temperature recovery; cough and sputum disappearance; and rale disappearance time), treatment effect, and laboratory indexes [procalcitonin (PCT), C-reactive protein (CRP), white blood cell count (WBC), and neutrophil percentage (NE)] before and 7 d after treatment and the incidence of adverse reactions were assessed. RESULTS: In the study group, the time to WBC normalization (6.79 ± 2.09 d), time to body temperature normalization (4.15 ± 1.08 d), time to disappearance of cough and sputum (6.19 ± 1.56 d), and time to disappearance of rales (6.68 ± 1.43 d) were shorter than those of the control group (8.89 ± 2.32 d, 5.81 ± 1.33 d, 8.77 ± 2.11 d, and 8.69 ± 2.12 d, respectively; P = 0.000). Total effective rate was higher in the study group (94.59% vs 75.68%, P = 0.022). Serum PCT (12.89 ± 3.96 µg/L), CRP (19.62 ± 6.44 mg/L), WBC (20.61 ± 6.38 × 109/L), and NE (86.14 ± 7.21%) levels of the study group before treatment were similar to those of the control group (14.05 ± 4.11 µg/L, 18.79 ± 5.96 mg/L, 21.21 ± 5.59 × 109/L, and 84.39 ± 6.95%, respectively) with no significant differences (P = 0.220, 0.567, 0.668, and 0.291, respectively). After 7 d of treatment, serum PCT, CRP, WBC, and NE levels in the two groups were lower than those before treatment. Serum PCT (2.01 ± 0.56 µg/L), CRP (3.11 ± 1.02 mg/L), WBC (5.10 ± 1.83 × 109/L), and NE (56.35 ± 7.17%) levels were lower in the study group than in the control group (3.29 ± 0.64 µg/L, 5.67 ± 1.23 mg/L, 8.13 ± 3.01 × 109/L, and 64.22 ± 8.08%, respectively; P = 0.000). There was no significant difference in the incidence of adverse reactions between the groups (7.50% vs 12.50%, P = 0.708). CONCLUSION: Piperacillin sodium/tazobactam sodium is superior to cefoperazone sodium/ sulbactam sodium in the treatment of elderly patients with respiratory tract infection with a similar safety profile.

16.
J Colloid Interface Sci ; 599: 730-740, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33984765

ABSTRACT

Hetero-MoO3/MoO2@N-doped carbon nanobelt anodes (h-MoO3/MoO2@NC) with long lifespan and superior rate capability were proposed by a simple in situ reduction tactic, in which pristine MoO3 was transformed into heterogeneous MoO3/MoO2. The hetero-MoO3/MoO2 architecture significantly improves the electronic conductivity and affords abundant oxygen deficiencies. Meanwhile, the synergistic effect of internal MoO3/MoO2 heterostructure and outer N-doped carbon layer (NC) accomplishes a balance of sustainable potassium/sodium storage and ultra-durable structure stability. In potassium ion batteries, the anodes steadily maintain a reversible capacity of 283 mAh g-1 after 6000 cycles at 0.5 A g-1 and 153 mAh g-1 after 1000 cycles under 2 A g-1, as well as an impressive rate capability of 131 mAh g-1 at 3 A g-1. In sodium ion batteries, the anodes purchase a steady capacity of 152 mAh g-1 even after 10,000 cycles at 2 A g-1, and 190 mAh g-1 after 5000 cycles at 0.5 A g-1. Moreover, the h-MoO3/MoO2@NC composite possesses a prominent pseudocapacitive effect and good thermal adaptability (-10 to 50 °C) in both KIBs and SIBs. The results indicate that the h-MoO3/MoO2@NC composite would be an auspicious material for potassium/sodium storage and other ion batteries.

17.
Angew Chem Int Ed Engl ; 59(10): 4009-4016, 2020 Mar 02.
Article in English | MEDLINE | ID: mdl-31851417

ABSTRACT

Fluorinated organoboranes serve as versatile synthetic precursors for the preparation of value-added fluorinated organic compounds. Recent progress has been mainly focused on the transition-metal catalyzed defluoroborylation. Herein, we report a photocatalytic defluoroborylation platform through direct B-H activation of N-heterocyclic carbene boranes, through the synergistic merger of a photoredox catalyst and a hydrogen atom transfer catalyst. This atom-economic and operationally simple protocol has enabled defluoroborylation of an extremely broad scope of multifluorinated substrates including polyfluoroarenes, gem-difluoroalkenes, and trifluoromethylalkenes in a highly selective fashion. Intriguingly, the defluoroborylation protocol can be transition-metal free, and the regioselectivity obtained is complementary to the reported transition-metal-catalysis in many cases.

18.
J Org Chem ; 84(20): 13104-13111, 2019 Oct 18.
Article in English | MEDLINE | ID: mdl-31497964

ABSTRACT

Commercially available 3,5-bis(trifluoromethyl)aniline was found to be a highly efficient monodentate transient directing group (MonoTDG) for the palladium-catalyzed direct dehydrogenative cross-coupling of benzaldehydes with arenes. A diverse set of symmetrical and unsymmetrical 9-fluorenones was readily obtained in yields of 32-72% along with excellent regioselectivities and broad functional group compatibility as well as high atom economy under mild conditions via a dual carbon-hydrogen (C-H) bond activation sequence.

19.
Angew Chem Int Ed Engl ; 58(36): 12580-12584, 2019 Sep 02.
Article in English | MEDLINE | ID: mdl-31310447

ABSTRACT

Chlorosilanes are versatile reagents in organic synthesis and material science. A mild pathway is now reported for the quantitative conversion of hydrosilanes to silyl chlorides under visible-light irradiation using neutral eosin Y as a hydrogen-atom-transfer photocatalyst and dichloromethane as a chlorinating agent. Stepwise chlorination of di- and trihydrosilanes was achieved in a highly selective fashion assisted by continuous-flow micro-tubing reactors. The ability to access silyl radicals using photocatalytic Si-H activation promoted by eosin Y offers new perspectives for the synthesis of valuable silicon reagents in a convenient and green manner.

20.
ChemSusChem ; 12(13): 3049-3053, 2019 Jul 05.
Article in English | MEDLINE | ID: mdl-30786170

ABSTRACT

Iron-catalyzed ortho C-H arylation and methylation reactions of pivalophenone N-H imines are reported. The pivaloyl N-H imine proved an excellent directing group for the arylation with diarylzinc reagents in the presence of an iron-diphosphine catalyst and 2,3-dichlorobutane at room temperature. A similar catalytic system also allowed methylation with Me3 Al at 70 °C. The pivaloyl imine of the product could be readily converted to a cyano group, thus allowing convenient preparation of ortho-functionalized benzonitriles.

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