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The catalytic cross-dehydrogenative coupling (CDC) reaction has received intense attention in recent years. The attractive feature of this coupling process is the formation of a CC bond from two CH moieties under oxidative conditions. In this Focus Review, recent advances in the palladium-catalyzed CDC reactions of C(sp2)H bond are summarized, with a focus on the period from 2011 to early 2013. [ABSTRACT FROM AUTHOR]

A C–H arylation with aryl chloride is made viable through a transition-metal-free approach. In the presence of a simple diol associating with KOt-Bu, various phenanthridine derivatives can be conveniently accessed. In particular, only 10 mol % of simple and inexpensive ethylene glycol is required for this protocol. These results represent the first general examples of aryl chloride/C–H coupling under transition-metal-free conditions. [ABSTRACT FROM AUTHOR]

Review: recent advances with a focus on the period from 2011 to early 2013; 96 refs. [ABSTRACT FROM AUTHOR]

Dehydrogenation An attractive feature of catalytic cross ‐ dehydrogenative coupling (CDC) reactions is the formation of a CC bond from two CH moieties under oxidative conditions. In their Focus Review on page 26   ff., Jun Wang, Fuk   Yee Kwong et   al. highlight recent advancements in palladium ‐ catalyzed C(sp2)C(sp2) bond formation through a dehydrogenative pathway. With the rocket ‐ like power catalyst system (i.e., palladium/ligand/oxidant), a variety of C(sp2)H bonds can be effectively zipped up through the expelling of H2 ‐ [oxidant]. [ABSTRACT FROM AUTHOR]

MYB transcription factor is one of the largest families in plants. There are more and more studies on plants responding to abiotic stress through MYB transcription factors, but the mechanism of some family members responding to salt stress is unclear. In this study, physiological and transcriptome techniques were used to analyze the effects of the R2R3-MYB transcription factor AtMYB72 on the growth and development, physiological function, and key gene response of Arabidopsis thaliana . Phenotypic observation showed that the damage of overexpression strain was more serious than that of Col-0 after salt treatment, while the mutant strain showed less salt injury symptoms. Under salt stress, the decrease of chlorophyll content, the degree of photoinhibition of photosystem II (PSII) and photosystem I (PSI) and the degree of oxidative damage of overexpressed lines were significantly higher than those of Col-0. Transcriptome data showed that the number of differentially expressed genes (DEGs) induced by salt stress in overexpressed lines was significantly higher than that in Col-0. GO enrichment analysis showed that the response of AtMYB72 to salt stress was mainly by affecting gene expression in cell wall ectoplast, photosystem I and photosystem II, and other biological processes related to photosynthesis. Compared with Col-0, the overexpression of AtMYB72 under salt stress further inhibited the synthesis of chlorophyll a (Chla) and down-regulated most of the genes related to photosynthesis, which made the photosynthetic system more sensitive to salt stress. AtMYB72 also caused the outbreak of reactive oxygen species and the accumulation of malondialdehyde under salt stress, which decreased the activity and gene expression of key enzymes in SOD, POD, and AsA-GSH cycle, thus destroying the ability of antioxidant system to maintain redox balance. AtMYB72 negatively regulates the accumulation of osmotic regulatory substances such as soluble sugar (SS) and soluble protein (SP) in A. thaliana leaves under salt stress, which enhances the sensitivity of Arabidopsis leaves to salt. To sum up, MYB72 negatively regulates the salt tolerance of A. thaliana by destroying the light energy capture, electron transport, and antioxidant capacity of Arabidopsis.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease that affects the entire gastrointestinal tract. The complex etiology of IBD made it difficult to cure. Phosphodiesterases (PDEs) have garnered significant attention due to their involvement in immune and inflammatory responses in IBD. Most recently, we have reported a novel PDE1 inhibitor 1 with quinolin-2(1H)-one scaffold, demonstrating anti-IBD effects. However, its short half-life (t 1/2 ) in the rat liver microsomes (RLMs) is relatively short. In this study, structural optimization of compound 1 was performed to improve metabolic stability. Combined with molecular docking and dynamics simulations, a series of quinolin-2(1H)-one derivatives were synthesized. Among them, compound 7a showed an excellent IC 50 value of 11 nM, high selectivity to PDE1 compared to other PDEs, and good metabolic stability with RLM t 1/2 of 67.3 min. The binding pattern between 7a and PDE1 revealed an additional hydrogen bond with Cys410, which could enhance the inhibitory activity. Furthermore, compound 7a demonstrated anti-inflammatory properties by reducing cytokine production and antioxidant activity in LPS-induced Raw264.7 cells, which contributed to its effectiveness against IBD. We believe that compound 7a could serve as an ideal tool for further pharmacological research on IBD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Phosphodiesterase 1 (PDE1) is a subfamily of PDE super enzyme families that can hydrolyze cyclic adenosine monophosphate and cyclic guanosine monophosphate simultaneously. Currently, the number of PDE1 inhibitors is relatively few, significantly limiting their application. Herein, a novel series of quinolin-2(1 H )-ones were designed rationally, leading to compound 10c with an IC 50 of 15 nM against PDE1C, high selectivity across other PDEs, and remarkable safety properties. Furthermore, we used the lead compound 10c as a chemical tool to explore whether PDE1 could work as a novel potential target for the treatment of inflammatory bowel disease (IBD), a disease which is a chronic, relapsing disorder of the gastrointestinal tract inflammation lacking effective treatment. Our results showed that administration of 10c exerted significant anti-IBD effects in the dextran sodium sulfate-induced mice model and alleviated the inflammatory response, indicating that PDE1 could work as a potent target for IBD.

Vascular dementia (VaD) is the second commonest type of dementia which lacks of efficient treatments currently. Neuroinflammation as a prominent pathological feature of VaD, is highly involved in the development of VaD. In order to verify the therapeutic potential of PDE1 inhibitors against VaD, the anti-neuroinflammation, memory and cognitive improvement were evaluated in vitro and in vivo by a potent and selective PDE1 inhibitor 4a . Also, the mechanism of 4a in ameliorating neuroinflammation and VaD was systematically explored. Furthermore, to optimize the drug-like properties of 4a , especially for metabolic stability, 15 derivatives were designed and synthesized. As a result, candidate 5f , with a potent IC 50 value of 4.5 nmol/L against PDE1C, high selectivity over PDEs, and remarkable metabolic stability, efficiently ameliorated neuron degeneration, cognition and memory impairment in VaD mice model by suppressing NF- κ B transcription regulation and activating cAMP/CREB axis. These results further identified PDE1 inhibition could serve as a new therapeutic strategy for treatment of VaD., Competing Interests: The authors declare no competing financial interest., (© 2022 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

Direct intermolecular C-H arylation employing aryl bromide as the arene source has been developed. This process proceeds via a simple transition-metal-free pathway. With the aid of inexpensive and commercially available 2-pyridyl carbinol and potassium tert-butoxide, various unactivated arene C-H bonds can be directly arylated by aryl bromides through homolytic aromatic substitution.

The catalytic cross-dehydrogenative coupling (CDC) reaction has received intense attention in recent years. The attractive feature of this coupling process is the formation of a C-C bond from two C-H moieties under oxidative conditions. In this Focus Review, recent advances in the palladium-catalyzed CDC reactions of C(sp(2) )-H bond are summarized, with a focus on the period from 2011 to early 2013., (Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Transition-metal-free cross-coupling reactions have been a hot topic in recent years. With the aid of a radical initiator, a number of unactivated arene C-H bonds can be directly arylated/functionalized by using aryl halides through homolytic aromatic substitution. Commercially available or specially designed promoters (e.g. diamines, diols, and amino alcohols) have been used to make this synthetically attractive method viable. This protocol offers an inexpensive, yet efficient route to aromatic C-C bond formations since transition metal catalysts and impurities can be avoided by using this reaction system. In this article, we focus on the significance of the reaction conditions (e.g. bases and promoters), which allow this type of reaction to proceed smoothly. Substrate scope limitations and challenges, as well as mechanistic discussion are also included., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)