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1.
Nat Commun ; 14(1): 8052, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38052783

ABSTRACT

[6,6]-Phenyl-C61-butyric acid methyl ester (PCBM), a star molecule in the fullerene field, has found wide applications in materials science. Herein, electrosynthesis of buckyballs with fused-ring systems has been achieved through radical α-C-H functionalization of the side-chain ester for both PCBM and its analogue, [6,6]-phenyl-C61-propionic acid methyl ester (PCPM), in the presence of a trace amount of oxygen. Two classes of buckyballs with fused bi- and tricyclic carbocycles have been electrochemically synthesized. Furthermore, an unknown type of a bisfulleroid with two tethered [6,6]-open orifices can also be efficiently generated from PCPM. All three types of products have been confirmed by single-crystal X-ray crystallography. A representative intramolecularly annulated isomer of PCBM has been applied as an additive to inverted planar perovskite solar cells and boosted a significant enhancement of power conversion efficiency from 15.83% to 17.67%.

2.
Endocr J ; 69(1): 23-33, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-34456194

ABSTRACT

Chronic stress affects the reproductive health of mammals; however, the impact of adrenocorticotropin hormone (ACTH) level elevation during chronic stress on the reproduction of weaned sows remains unclear. In this study, nine weaned sows with the same parturition date were randomly divided into control group (n = 4) and ACTH group (n = 5). Each group received intravenous administration of ACTH three times daily for 7 days. Blood samples were collected every 3 h after injection. A radioimmunoassay was used to measure the concentrations of cortisol, luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P4) and estradiol-17ß (E2) in the blood. Estrus was determined according to changes in the vulva and the boar contact test. The mRNA expressions of glucocorticoid receptor, FSH receptor, LH receptor (LHR) in the corpus luteum (CL) were detected by qRT-PCR. The results showed that ACTH administration substantially delayed the initiation of estrus and the pre-ovulatory LH peak. The sows of control group ovulated within 10 days and the ovulation rate was 100%, while it was 60% in the ACTH group. Two sows of ACTH group showed pseudo-estrus. The E2 concentrations significantly decreased in the ACTH group at 36 h, 42 h and 66 h of the experimental period. The P4 concentrations in the ACTH group significantly decreased at 132, 138, and 147 h of the experimental period. ACTH significantly reduced the LHR mRNA expression in CLs. In conclusion, long-term repeated ACTH administration affects the endocrinology, estrus onset, and ovarian function of weaned sows.


Subject(s)
Adrenocorticotropic Hormone , Estrus , Adrenocorticotropic Hormone/pharmacology , Animals , Estradiol , Estrus/physiology , Female , Luteinizing Hormone , Mammals/metabolism , Ovulation , Progesterone , Swine , Weaning
3.
Research (Wash D C) ; 2020: 2059190, 2020.
Article in English | MEDLINE | ID: mdl-32149279

ABSTRACT

With the recent advance in chemical modification of fullerenes, electrosynthesis has demonstrated increasing importance in regioselective synthesis of novel fullerene derivatives. Herein, we report successively regioselective synthesis of stable tetra- and hexafunctionalized [60]fullerene derivatives. The cycloaddition reaction of the electrochemically generated dianions from [60]fulleroindolines with phthaloyl chloride regioselectively affords 1,2,4,17-functionalized [60]fullerene derivatives with two attached ketone groups and a unique addition pattern, where the heterocycle is rearranged to a [5,6]-junction and the carbocycle is fused to an adjacent [6,6]-junction. This addition pattern is in sharp contrast with that of the previously reported biscycloadducts, where both cycles are appended to [6,6]-junctions. The obtained tetrafunctionalized compounds can be successively manipulated to 1,2,3,4,9,10-functionalized [60]fullerene derivatives with an intriguing "S"-shaped configuration via a novel electrochemical protonation. Importantly, the stability of tetrafunctionalized [60]fullerene products allows them to be applied in planar perovskite solar cells as efficient electron transport layers.

4.
Chem Sci ; 11(2): 384-388, 2020 Jan 14.
Article in English | MEDLINE | ID: mdl-32153753

ABSTRACT

The efficient and regioselective electrosynthesis of tetra- and hexa-functionalized [60]fullerene derivatives with unprecedented addition patterns has been achieved. The tetra-functionalized [60]fullerene derivative with an intriguing 1,2,4,17-addition pattern is regioselectively obtained by cyclization reaction of the dianionic species generated electrochemically from a [60]fulleroindoline with 1,2-bis(bromomethyl)benzene at 0 °C, and can be converted to the more stable 1,2,3,4-adduct at 25 °C. Furthermore, the hexa-functionalized [60]fullerene derivative with the 1,2,3,4,9,10-addition pattern displaying a unique "S"-shaped configuration can be synthesized by protonation of the electrochemically generated dianion of the obtained tetra-functionalized 1,2,4,17-adduct. The structures of the tetra- and hexa-functionalized products have been determined by spectroscopic data and single-crystal X-ray analysis.

5.
R Soc Open Sci ; 4(9): 170658, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28989769

ABSTRACT

Atmospheric pressure nonequilibrium plasma jet has been applied to the synthesis of [60]fullerene oxides (C60On) for the first time. C60O and C60O2 were produced and isolated in high yields up to 44% and 21%, respectively. The structural assignment of C60O was confirmed by comparison with the reported spectroscopic data. Theoretical calculations of 13C NMR chemical shifts for eight isomers of C60O2 were performed and compared with the experimental data to assign the most possible structure for the obtained C60O2 dominantly as an e isomer.

6.
J Org Chem ; 81(24): 12223-12231, 2016 12 16.
Article in English | MEDLINE | ID: mdl-27978713

ABSTRACT

Two visible light-harvesting perylenebisimide (PDI)-[60]fullerene (C60) systems, dyad P1 with one C60 unit and triad P2 with two C60 units, have been synthesized. Both systems are axially symmetrical with a rigid biphenyl linker, ensuring a relatively fixed spatial distance between the donor and acceptor, preventing through-space interaction, and enhancing energy transfer. Steady-state and transient spectroscopy, electrochemistry, as well as theoretical calculations have been used to investigate the electrochemical and photophysical properties of the two systems. Steady-state and time-resolved spectroscopy demonstrate that the excited state is featured by an efficient intramolecular energy transfer from PDI to C60. Then, the high efficient intrinsic intersystem crossing of C60 eventually leads to the production of the triplet C60. The extensive visible light absorption of PDI in the range of 400-650 nm and the final localization of the excited energy at the triplet C60 make these compounds ideal singlet oxygen inducers. Further investigation shows that the photooxidation capability for both compounds is significantly enhanced with respect to either PDI or C60 and even better than that of the commonly used triplet photosensitizer methylene blue (MB). The double C60 moieties in P2 display a better result, and the photooxidation efficiency of P2 increases 1.3- and 1.4-fold compared to that of P1 and MB, respectively. The combination of a light-harvesting unit with an intersystem crossing unit results in a highly efficient photooxidation system, which opens up a new way to triplet photosensitizer design.

7.
Chem Commun (Camb) ; 51(30): 6548-51, 2015 Apr 18.
Article in English | MEDLINE | ID: mdl-25766768

ABSTRACT

A cuprous bromide-catalyzed heteroannulation reaction of [60]fullerene with ketoxime acetates has been exploited to prepare novel 1-fulleropyrrolines through the cleavage of N-O and C-H bonds and formation of C-C and C-N bonds under thermal conditions. A plausible mechanism for the formation of 1-fulleropyrrolines is proposed on the basis of the experimental results. The electrochemistry of the obtained products has also been investigated.

8.
J Am Chem Soc ; 135(42): 15794-800, 2013 Oct 23.
Article in English | MEDLINE | ID: mdl-24066644

ABSTRACT

A self-decoupled porphyrin with a tripodal anchor has been synthesized and deposited on Au(111) using different wet-chemistry methods. Nanoscale electroluminescence from single porphyrin molecules or aggregates on Au(111) has been realized by tunneling electron excitation. The molecular origin of the luminescence is established by the vibrationally resolved fluorescence spectra observed. The rigid tripodal anchor not only acts as a decoupling spacer but also controls the orientation of the molecule. Intense molecular electroluminescence can be obtained from the emission enhancement provided by a good coupling between the molecular transition dipole and the axial nanocavity plasmon. The unipolar performance of the electroluminescence from the designed tripodal molecule suggests that the porphyrin molecule is likely to be excited by the injection of hot electrons, and then the excited state decays radiatively through Franck-Condon π*-π transitions. These results open up a new route to generating electrically driven nanoscale light sources.

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