Regioselective α-Phosphonylation of Unprotected Alicyclic Amines.

Unprotected alicyclic amines undergo α-C-H bond phosphonylation via a two-stage one-pot process involving the oxidation of amine-derived lithium amides with simple ketone oxidants, generating transient imines which are then captured with phosphites or phosphine oxides. Amines with an existing α-substituent undergo regioselective α'-phosphonylation. Amine α-arylation and α'-phosphonylation can be combined, generating a difunctionalized product in a single operation.

Oxidative Free-Radical C(sp2)-H Bond Chlorination of Enaminones with LiCl: Access to Highly Functionalized α-Chlorinated Enaminones.

An oxidative free-radical C(sp2)-H bond chlorination strategy of enaminones has been developed by using LiCl as a chlorinating reagent and K2S2O8 as an oxidant. This transformation provides a new and straightforward synthetic methodology to afford highly functionalized α-chlorinated enaminones with a Z-configuration in good to excellent yields.

Divergent Synthesis of 2-Chromonyl-3-hydrazono-chromones and 2-Alkoxy-3-hydrazono-chromones through Switchable Annulation Reactions of o-Hydroxyphenylenaminones with Aryldiazonium Salts.

An unprecedented selective chromone annulation reaction controlled by solvent for the divergent synthesis of two types of 2,3-disubstituted chromone skeletons has been developed. A variety of 2-chromonyl-3-hydrazono-chromones and 2-alkoxy-3-hydrazono-chromones were constructed efficiently from readily available o-hydroxyphenylenaminones (o-HPEs) and aryldiazonium salts at room temperature. This strategy is highly chemoselective and features mild reaction conditions, broad substrate scope, broad functional group tolerance, easy gram-scale preparation, and simple filtration to obtain the pure products without tedious column chromatography.

Switchable Skeletal Rearrangement of Hexahydro-4H-indol-4-ones: Divergent Synthesis of Dihydroxy-4H-cyclopenta[b]pyridin-4-ones and 8-Alkenyl Oxepane-2,6-diones.

An unprecedented base-controlled selective skeletal rearrangement reaction of hexahydro-4H-indol-4-ones has been developed. In this protocol, highly functionalized dihydroxy-4H-cyclopenta[b]pyridin-4-ones and 8-alkenyl oxepane-2,6-diones were prepared with a broad substrate scope and high chemoselectivity in moderate to excellent yields selectively by modulating LiOH and Et3N. In addition, the newly formed 8-alkenyl oxepane-2,6-dione scaffolds could be easily further derivatized to 5-(pyrrol-2-yl)dihydrofuran-2(3H)-ones through a rare intramolecular rearrangement reaction.

Mitigation of myocardial ischemia/reperfusion-induced chronic heart failure via Shexiang Baoxin Pill-mediated regulation of the S1PR1 signaling pathway.

BACKGROUND: Well-defined and effective pharmacological interventions for clinical management of myocardial ischemia/reperfusion (MI/R) injury are currently unavailable. Shexiang Baoxin Pill (SBP), a traditional Chinese medicine Previous research on SBP has been confined to single-target treatments for MI/R injury, lacking a comprehensive examination of various aspects of MI/R injury and a thorough exploration of its underlying mechanisms. PURPOSE: This study aimed to investigate the therapeutic potential of SBP for MI/R injury and its preventive effects on consequent chronic heart failure (CHF). Furthermore, we elucidated the specific mechanisms involved, contributing valuable insights into the potential pharmacological interventions for the clinical treatment of MI/R injury. METHODS: We conducted a comprehensive identification of SBP components using high-performance liquid chromatography. Subsequently, we performed a network pharmacology analysis based on the identification results, elucidating the key genes influenced by SBP. Thereafter, through bioinformatics analysis of the key genes and validation through mRNA and protein assays, we ultimately determined the centralized upstream targets. Lastly, we conducted in vitro experiments using myocardial and endothelial cells to elucidate and validate potential underlying mechanisms. RESULTS: SBP can effectively mitigate cell apoptosis, oxidative stress, and inflammation, as well as promote vascular regeneration following MI/R, resulting in improved cardiac function and reduced CHF risk. Mechanistically, SBP treatment upregulates sphingosine-1-phosphate receptor 1 (S1PR1) expression and activates the S1PR1 signaling pathway, thereby regulating the expression of key molecules, including phosphorylated Protein Kinase B (AKT), phosphorylated signal transducer and activator of transcription 3, epidermal growth factor receptor, vascular endothelial growth factor A, tumor necrosis factor-α, and p53. CONCLUSION: This study elucidated the protective role of SBP in MI/R injury and its potential to reduce the risk of CHF. Furthermore, by integrating downstream effector proteins affected by SBP, this research identified the upstream effector protein S1PR1, enhancing our understanding of the pharmacological characteristics and mechanisms of action of SBP. The significance of this study lies in providing compelling evidence for the use of SBP as a traditional Chinese medicine for MI/R injury and consequent CHF prevention.

DAHOS Study: Efficacy of dapagliflozin in treating heart failure with reduced ejection fraction and obstructive sleep apnea syndrome - A 3-month, multicenter, randomized controlled clinical trial.

BACKGROUND: The recent discovery of new therapeutic approaches to heart failure with reduced ejection fraction (HFrEF), including sodium-glucose cotransporter-2 (SGLT-2) inhibitors, as well as improved treatment of co-morbidities has provided much needed help to HFrEF. In addition, dapagliflozin, one of the SGLT-2 inhibitors, serves as a promising candidate in treating obstructive sleep apnea (OSA) of HFrEF patients due to its likely mechanism of countering the pathophysiology of OSA of HFrEF. METHODS: This 3-month multicenter, prospective, randomized controlled trial enrolled participants with left ventricular ejection fraction (LVEF) less than 40% and apnea-hypopnea index (AHI) greater than 15. Participants were randomized into two groups: the treatment group received optimized heart failure treatment and standard-dose dapagliflozin, while the control group only received optimized heart failure treatment. The primary endpoint was the difference in AHI before and after treatment between the two groups. Secondary endpoints included oxygen desaturation index (ODI), minimum oxygen saturation, longest apnea duration, inflammatory factors (CRP, IL-6), quality of life score, and LVEF. RESULTS: A total of 107 patients were included in the final analysis. AHI, LVEF and other baseline data were similar for the dapagliflozin and control groups. After 12 weeks of dapagliflozin treatment, the dapagliflozin group showed significant improvements in sleep parameters including AHI, HI, longest pause time, ODI, time spent with SpO2 < 90%, and average SpO2. Meanwhile, the control group showed no significant changes in sleep parameters, but did demonstrate significant improvements in left ventricular end-diastolic diameter, LVEF, and NT-proBNP levels at 12 weeks. In the experimental group, BMI was significantly reduced, and there were improvements in ESS score, MLHFQ score, and EQ-5D-3L score, as well as significant reductions in CRP and IL-6 levels, while the CRP and IL-6 levels were not improved in the control group. The decrease in LVEF was more significant in the experimental group compared to the control group. There were no significant differences in the magnitude of the decreases between the two groups. CONCLUSIONS: Dapagliflozin may be an effective treatment for heart failure complicated with OSA, and could be considered as a potential new treatment for OSA. (Trial registration  www.chictr.org.cn , ChiCTR2100049834. Registered 10 August 2021).

Platelet Membrane Nanocarriers Cascade Targeting Delivery System to Improve Myocardial Remodeling Post Myocardial Ischemia-Reperfusion Injury.

Although treatments for myocardial infarction have advanced significantly, the global mortality due to ischemia and subsequent reperfusion injury remains high. Here, a platelet (PLT) membrane nanocarrier (PL720) that encapsulates L-arginine and FTY720 to facilitate the cascade-targeted delivery of these substances to the myocardial injury site and enable the controlled release of L-arginine and FTY720 is developed. Such an innovative approach shows enhanced cardioprotection through multiple target strategies involved in ischemia-reperfusion injury and late reperfusion inflammation. During the ischemia-reperfusion phase, PL720 targets and accumulates in damaged coronary arteries. PL720 rapidly releases L-arginine, stimulating endothelial cells to produce NO, thereby dilating blood vessels and promoting blood flow recovery, while FTY720's sustained release exerts anti-apoptotic effects. During the late reperfusion inflammatory phase, PL720 is captured by circulating inflammatory monocytes and transported into a deeper ischemic myocardial lesion. PL720 promotes macrophage polarization and accelerates the inflammatory repair. Furthermore, the issue of bradycardia associated with the clinical use of FTY720 is innovatively relieved. Therefore, PL720 is a vascular injury and inflammation dual targeting strategy, exhibiting significant potential for multi-targeted therapy and clinical translation for cardiac injury.

Rh(III)-catalyzed selective mono- and dual-functionalization/cyclization of 1-aryl-5-aminopyrazoles with iodonium ylides.

An efficient Rh(III)-catalyzed selective mono- and dual-C-H bond functionalization/cyclization with iodonium ylide as a single coupling partner was demonstrated, in which fused benzodiazepine skeletons were obtained in excellent yields. This method greatly improved an effective approach to dual C-H unsymmetrical functionalization.

Smart Home Sleep Respiratory Monitoring System Based on a Breath-Responsive Covalent Organic Framework.

A smart home sleep respiratory monitoring system based on a breath-responsive covalent organic framework (COF) was developed and utilized to monitor the sleep respiratory behavior of real sleep apnea patients in this work. The capacitance of the interdigital electrode chip coated with COFTPDA-TFPy exhibits thousands-level reversible responses to breath humidity gases, with subsecond response time and robustness against environmental humidity. A miniaturized printed circuit board, an open-face-mask-based respiratory sensor, and a smartphone app were constructed for the wearable wireless smart home sleep respiratory monitoring system. Leveraging the sensitive and rapid reversible response of COFs, the COF-based respiratory monitoring system can effectively record normal breath, rapid breath, and breath apnea, enabling over a thousand cycles of hour-level continuous monitoring during daily wear. Next, we took the groundbreaking step of advancing the humidity sensor to the clinical trial stage. In clinical experiments on real sleep apnea patients, the COF-based respiratory monitoring system successfully recorded hour-level sleep respiratory data and differentiated the breathing behavior characteristics and severity of sleep apnea patients and subjects with normal sleep function and primary snoring patients. This work successfully advanced humidity sensors into clinical research for real patients and demonstrated the enormous application potential of COF materials in clinical diagnosis.

Synthesis of Tetrahydro-indolones through Rh(III)-Catalyzed [3 + 2] Annulation of Enaminones with Iodonium Ylides.

An unprecedented protocol for a Rh(III)-catalyzed [3 + 2] annulation from simple and readily available enaminones and iodonium ylides has been developed. The novel strategy allows for access to a new class of structurally diverse tetrahydro-indolones with high efficiency and a broad substrate scope. In addition, this transformation represents the first example of the selective Rh(III)-catalyzed alkenyl C-H bond functionalization and annulation of enaminones. Finally, the potential applications of this protocol are demonstrated through gram-scale reaction and late-stage modification.

Construction of 1,4-Dihydropyridines: The Evolution of C4 Source.

The field of cascade cyclization for the construction of 1,4-dihydropyridines (1,4-DHPs) has been continuously expanding during the last decades because of their broad-spectrum biological and synthetic importance. To date, many methods have been developed, mainly including the Hantzsch reaction, Hantzsch-like reaction and newly developed cascade cyclization, in which various synthons have been successively developed as C4 sources of 1,4-DHPs. This review presents the cascade cyclization synthesis strategy for the construction of 1,4-DHPs according to various C4 sources from carbonyl compounds, alkenyl fragments, alcohols, aliphatic amines, glycines and other C4 sources.

Rh(III)-Catalyzed [3 + 2] Annulation/Pinacol Rearrangement Reaction of Enaminones with Iodonium Ylides: Direct Synthesis of 2-Spirocyclo-pyrrol-3-ones.

A novel Rh(III)-catalyzed cascade alkenyl C-H activation/[3 + 2] annulation/pinacol rearrangement reaction of enaminones with iodonium ylides has been developed. This methodology provides a new and straightforward synthetic strategy to afford highly functionalized 2-spirocyclo-pyrrol-3-ones in satisfactory yield from readily available starting materials under mild conditions. Moreover, gram-scale reactions and further derivatization experiments are implemented to demonstrate the potential utility of this developed approach.

Synthesis of 4-Alkylated 1,4-Dihydropyridines: Fe(II)-Mediated Oxidative Cascade Cyclization Reaction of Cyclic Ethers with Enaminones.

Syntheses of highly functionalized 4-alkylated 1,4-dihydropyridines (1,4-DHPs) from cyclic ethers and enaminones via iron(II)-mediated oxidative free radical cascade C(sp3)-H bond functionalization/C(sp3)-O bond cleavage/cyclization reaction have been first developed. This novel synthetic strategy offers an alternative method for the construction of 1,4-DHPs by using esters as the C4 sources, as well as expands the application of ethers in heterocycle synthesis.

Fe-mediated oxidative cascade [1 + 2 + 3]-cyclization/esterification reaction: synthesis of 4-alkylated 1,4-dihydropyridines.

An Fe-mediated four-component reaction of enaminones, anhydrides and tetrahydrofuran through a cascade [1 + 2 + 3]-cyclization/esterification process is presented. This protocol provides a new and effective method to construct 4-alkylated 1,4-dihydropyridines with an ester fragment. Cyclic ether is employed as the C4 source of 1,4-dihydropyridines for the first time.

Efficacy of dapagliflozin in the treatment of HFrEF with obstructive sleep apnea syndrome (DAHOS study): study protocol for a multicentric, prospective, randomized controlled clinical trial.

BACKGROUND: Heart failure with reduced ejection fraction (HFrEF) is associated with sleep dyspnea (SDB), which plays an adverse role in the pathophysiology of the condition. SDB management in HFrEF, however, remains controversial. HFrEF's medical management has recently made significant progress with the discovery of new therapeutic avenues, namely sodia-glucose cotransporter-2 (SGLT-2) inhibitors, and better treatment of co-morbidities. Dapagliflozin, one of the SGLT-2 inhibitors, is a good candidate for correcting SDB of HFrEF patients because their known mechanisms of action are likely to counteract the pathophysiology of SDB in HFrEF. METHODS/DESIGN: The trial is a 3-month, multicentric, prospective, randomized controlled clinical study. Patients (i.e., adults with left ventricular ejection fraction ≤ 40%, Apnoea-Hypopnoea Index ≥ 15) will be randomized to receive optimized heart failure therapy plus a standard dose of dapagliflozin, while the control group will receive only optimized heart failure therapy. Patients will be evaluated before and after 3 months (nocturnal ventilatory polygraphy, echocardiography, laboratory testing, and quality-of-life and SDB questionnaires). The primary outcome is the change in the Apnoea-Hypopnoea Index, before and after 3 months of treatment. TRIAL REGISTRATION: www.chictr.org.cn , ChiCTR2100049834. Registered 10 August 2021.

Access to thiionized-, selenolized-, and alkylated 5-alkylidene 3-pyrrolin-2-one derivatives via a regioselective oxidative annulation reaction.

A metal-free regioselective oxidative annulation reaction of readily available 2,4-pentanediones with primary amines has been described. This protocol provides a divergent strategy for the incorporation of various radical donors into 5-alkylidene 3-pyrrolin-2-one skeletons, producing a variety of thiionized-, selenolized-, and alkylated 5-alkylidene 3-pyrrolin-2-one derivatives. Moreover, the diverse synthetic transformations of the 5-alkylidene 3-pyrrolin-2-one products were also investigated.

Copper-Catalyzed Oxidative [1+2+1+2] Cascade Cyclization of N,N-Dimethyl Enaminones with Benzylamines: A Facile Access to Functionalized 1,4-Dihydropyridines.

Using benzylamines as the C4 source of 1,4-dihydropyridines (1,4-DHPs), a Cu-catalyzed oxidative [1+2+1+2] cascade cyclization for the synthesis of 1,4-DHPs was firstly developed. A broad range of easily available N,N-dimethyl enaminones and benzylamines are employed smoothly to provide a diverse range of 1,4-DHPs with high efficiency. This method is performed by a one-pot cascade C(sp3 )-H bond functionalization/C(sp3 )-N cleavage/cyclization strategy to form simultaneously two C(sp3 )-C(sp2 ) bonds, two C(sp2 )-N bonds, and a 1,4-DHP ring.

Prevalence and clinical characteristics of sleep-disordered breathing in patients with heart failure of different left ventricular ejection fractions.

PURPOSES: The prevalence of sleep-disordered breathing (SDB) is high in patients with heart failure (HF), while the prevalence of SDB in HF with different left ventricular ejection fractions (LVEF) has rarely been reported. We aimed to explore the prevalence and clinical characteristics of SDB in patients with HF having different LVEF. METHODS: Patients with stable HF were consecutively enrolled. All patients underwent portable overnight cardiorespiratory polygraphy and echocardiography. According to their LVEF, the patients were divided into the HFrEF (HF with reduced EF, EF < 40%), HFmrEF (HF with mid-range EF, 40 ≤ EF < 50), and HFpEF groups (HF with preserved EF, EF ≥ 50%). The prevalence and clinical data of SDB among the 3 groups were then compared. RESULTS: A total of 252 patients, including 134 men, were enrolled in the study. The prevalence of SDB in patients with HF was 70%. Obstructive sleep apnea (OSA) was diagnosed in 48% and central sleep apnea (CSA) in 22%. The prevalence of SDB in the HFrEE, HFmrEF, and HFpEF groups was 86%, 86%, and 62%, respectively (P = 0.001). The prevalence of OSA among the 3 groups was 42%, 47%, and 49%, respectively (P = 0.708), while the prevalence of CSA among the 3 groups was 44%, 40%, and 13% (P < 0.001). Logistic regression analysis revealed that age and BMI were independent risk factors for OSA in patients with HF, while LVEF and smoking were independent risk factors for CSA in patients with HF. Correlational analyses revealed that LVEF was negatively correlated with apnea-hypopnea index (AHI) (r = -0.309, P < 0.001) and central apnea index (CAI) ( r = -0.558, P < 0.001), while there was no significant correlation with obstructive apnea index (OAI). The ROC curve revealed that LVEF could predict the occurrence of CSA and SDB, with AUC = 0.683 (95%CI 0.600-0.767, P < 0.001) and AUC = 0.630 (95%CI 0.559-0.702, P = 0.001), but not of OSA. CONCLUSIONS: SDB was highly common in HF, and the prevalence of SDB was different in HF with different LVEF, mainly due to the difference in cardiac functions. The prevalence and severity of SDB in HFrEF and HFmrEF were significantly higher than those in HFpEF, which was mainly related to the increase in CSA. When HFmrEF was similar to HFrEF in cardiac functions, the prevalence, type, and severity of SDB were similar between the two groups. Changes in LVEF had a significant impact on CAI, but not on OAI. LVEF can predict the occurrence of CSA and SDB to a certain extent.

Facile access to the 2,2-difluoro-2,3-dihydrofuran skeleton without extra additives: DMF-promoted difluorocarbene formation of ClCF2CO2Na.

A practical and facile difluorocarbene-triggered cycloaddition reaction of enaminones was developed, which delivered 2,2-difluoro-2,3-dihydrofurans with a broad substrate scope. Notably, the reaction proceeded smoothly without any extra additives. Readily available sodium chlorodifluoroacetate (ClCF2CO2Na, SCDA) served as a difluorocarbene precursor in this transformation through DMF-promotion. Moreover, it is proved that the 2,2-difluoro-2,3-dihydrofuran derivatives exhibit potential antiproliferative activity against human tumour cells HeLa, MCF7 and HepG2.

Transition-metal-free approach to quinolines via direct oxidative cyclocondensation reaction of N,N-dimethyl enaminones with o-aminobenzyl alcohols.

A transition-metal-free method for the construction of 3-substituted or 3,4-disubstituted quinolines from readily available N,N-dimethyl enaminones and o-aminobenzyl alcohols is reported. The direct oxidative cyclocondensation reaction tolerates broad functional groups, allowing the efficient synthesis of various quinolines in moderate to excellent yields. The reaction involves a C (sp3)-O bond cleavage and a C=N bind and a C=C bond formation during the oxidative cyclization process, and the mechanism was proposed.