A bipolar disorder-associated missense variant alters adenylyl cyclase 2 activity and promotes mania-like behavior.

The single nucleotide polymorphism rs13166360, causing a substitution of valine (Val) 147 to leucine (Leu) in the adenylyl cyclase 2 (ADCY2), has previously been associated with bipolar disorder (BD). Here we show that the disease-associated ADCY2 missense mutation diminishes the enzyme´s capacity to generate the second messenger 3',5'-cylic adenosine monophosphate (cAMP) by altering its subcellular localization. We established mice specifically carrying the Val to Leu substitution using CRISPR/Cas9-based gene editing. Mice homozygous for the Leu variant display symptoms of a mania-like state accompanied by cognitive impairments. Mutant animals show additional characteristic signs of rodent mania models, i.e., they are hypersensitive to amphetamine, the observed mania-like behaviors are responsive to lithium treatment and the Val to Leu substitution results in a shifted excitatory/inhibitory synaptic balance towards more excitation. Exposure to chronic social defeat stress switches homozygous Leu variant carriers from a mania- to a depressive-like state, a transition which is reminiscent of the alternations characterizing the symptomatology in BD patients. Single-cell RNA-seq (scRNA-seq) revealed widespread Adcy2 mRNA expression in numerous hippocampal cell types. Differentially expressed genes particularly identified from glutamatergic CA1 neurons point towards ADCY2 variant-dependent alterations in multiple biological processes including cAMP-related signaling pathways. These results validate ADCY2 as a BD risk gene, provide insights into underlying disease mechanisms, and potentially open novel avenues for therapeutic intervention strategies.

Efficacy and prognostic value of peripheral blood CD4+ T cells and serum IL-6 and IL-8 in tuberculous meningitis.

Objective: To investigate the value of peripheral blood clusters of differentiation 4 (CD4+) T-lymphocyte (T cells) count and serum interleukin-6 (IL-6) and interleukin-8 (IL-8) in the treatment and prognosis of tuberculous meningitis (TBM). Methods: Sixty-five patients with TBM were prospectively included in the observation group. Sixty-five patients with pulmonary TB and a group of 65 healthy individuals served as the control groups. The differences in peripheral blood CD4+ T-cell count, serum IL-6, and IL-8 levels were compared, and changes in these indices after anti-TB treatment in the observation group were analysed. The observation group was divided into effective and ineffective groups based on their response after 24 weeks of anti-TB treatment. The study also evaluated the influence of peripheral blood CD4+ T-cell count, serum IL-6, and IL-8 levels on the adverse prognosis of TBM during anti-TB treatment. Results: Before treatment, the CD4+ T-cell count in the peripheral blood of the observation group was lower than in both the control and healthy groups, and serum IL-6 and IL-8 levels were higher than in the control group (P < 0.001). After 24 weeks of anti-TB treatment, the CD4+ T-cell count in the peripheral blood of the observation group increased, whereas the levels of IL-6 and IL-8 decreased significantly (P < 0.001). The levels of CD4+ T cells and IL-6 in the peripheral blood of patients before treatment were identified as independent factors influencing the efficacy of anti-TB treatment (odds ratio [OR] = 0.989, 95 % confidence interval [CI]: 0.980-0.997; OR = 1.010, 95 % CI: 1.003-1.017). Conclusion: In patients with TBM, the CD4+ T-cell count in the peripheral blood is decreased, whereas serum IL-6 and IL-8 are increased. The combination of CD4+ T cells and IL-8 shows a degree of predictive value for the prognosis of anti-TB treatment.

[Responses of radial growth of Fraxinus mandshurica from different provenances to climate at Maoershan in Northeast China]. / 东北地区帽儿山种源实验林区不同种源水曲柳径向生长对气候的响应.

To understand the responses of radial growth of Fraxinus mandshurica from different provenances to climatic factors, we used the dendrochronological method to establish the standard chronologies of F. mandshurica from 20 provenances in Maoershan provenance test forest, and analyzed the differences in radial growth and their correlation with climate factors. The results showed that the overall trend of F. mandshurica chronologies from 20 provenances was generally similar. There were differences in growth amplitude, with the average radial growth of F. mandshurica from Dailing, Lushuihe and Sanchazi being the highest. The radial growth of F. mandshurica from 20 provenances was significantly positively correlated with the highest temperature in July and the average temperature in July except for Huinan. The radial growth of F. mandshurica from 14 provenances was significantly positively correlated with the precipitation in August. The radial growth of F. mandshurica was constrained by temperature and precipitation during the growing season. There was difference in radial growth among F. mandshurica from different provenances under drought stress. F. mandshurica from Wangqing, Dailing, and Hailin had stronger resistance to drought, while that from Wandianzi, Zhanhe, and Xinglong had better recovery ability after drought.

PKCδ serves as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in Alzheimer's disease.

INTRODUCTION: To investigate the role of a novel type of protein kinase C delta (PKCδ) in the neuroinflammation of Alzheimer's disease (AD). METHODS: We analyzed PKCδ and inflammatory cytokines levels in cerebrospinal fluid (CSF) of AD and normal controls, as well as their correlations. The cellular expression pattern of PKCδ and the effects of PKCδ modulation on microglia-mediated neuroinflammation were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, RNA sequencing (RNA-seq), and immunofluorescence staining. RESULTS: PKCδ levels were increased dramatically in the CSF of AD patients and positively correlated with cytokines. PKCδ is expressed mainly in microglia in the brain. Amyloid beta (Aß) stimulation increased PKCδ expression and secretion, which led to upregulation of the nuclear factor kappa B (NF-κB) pathway and overproduction of proinflammatory cytokines. Downregulation or inhibition of PKCδ attenuated Aß-induced microglial responses and improved cognitive function in an AD mouse model. DISCUSSION: Our study identifies PKCδ as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD. HIGHLIGHTS: Protein kinase C delta (PKCδ) levels increase in cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD), and positively correlate with elevated inflammatory cytokines in human subjects. PKCδ is expressed mainly in microglia in vivo, whereas amyloid beta (Aß) stimulation increases PKCδ expression and secretion, causing upregulation of the nuclear factor kappa B (NF-κB) pathway and production of inflammatory cytokines. Downregulation or inhibition of PKCδ attenuates Aß-enhanced NF-κB signaling and cytokine production in microglia and improves cognitive function in AD mice. PKCδ serves as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD.

Development and validation of a nomogram to predict risk of septic cardiomyopathy in the intensive care unit.

The aim of this study was to develop a simple but effective nomogram to predict risk of septic cardiomyopathy (SCM) in the intensive care unit (ICU). We analyzed data from patients who were first admitted to the ICU for sepsis between 2008 and 2019 in the MIMIC-IV database, with no history of heart disease, and divided them into a training cohort and an internal validation cohort at a 7:3 ratio. SCM is defined as sepsis diagnosed in the absence of other cardiac diseases, with echocardiographic evidence of left (or right) ventricular systolic or diastolic dysfunction and a left ventricular ejection fraction (LVEF) of less than 50%. Variables were selected from the training cohort using the Least Absolute Shrinkage and Selection Operator (LASSO) regression to develop an early predictive model for septic cardiomyopathy. A nomogram was constructed using logistic regression analysis and its receiver operating characteristic (ROC) and calibration were evaluated in two cohorts. A total of 1562 patients participated in this study, with 1094 in the training cohort and 468 in the internal validation cohort. SCM occurred in 13.4% (147 individuals) in the training cohort, 16.0% (75 individuals) in the internal validation cohort. After adjusting for various confounding factors, we constructed a nomogram that includes SAPS II, Troponin T, CK-MB index, white blood cell count, and presence of atrial fibrillation. The area under the curve (AUC) for the training cohort was 0.804 (95% CI 0.764-0.844), and the Hosmer-Lemeshow test showed good calibration of the nomogram (P = 0.288). Our nomogram also exhibited good discriminative ability and calibration in the internal validation cohort. Our nomogram demonstrated good potential in identifying patients at increased risk of SCM in the ICU.

[Research Progress on Role of Long Non-Coding RNA in Occurrence and Development of Acute Myeloid Leukemia--Review].

In recent years, the importance of long non-coding RNA (lncRNA) in acute myeloid leukemia (AML) has attracted wide attention. Among them, lncRNAs that play a role in promoting cancer mainly include HOTAIR, UCA1, H19, ITGB2-AS1 and some genes of SNHG family, while in tumor suppression mainly include H22954, NEAT1, SNHG4, LINC01128 , etc. This article reviews the role of lncRNAs in the occurrence and development of AML, as well as those related to AML resistance and prognosis assessment, so as to provide a theoretical basis for the diagnosis and prognosis analysis of AML.

Drought shortens subtropical understory growing season by advancing leaf senescence.

Subtropical forests, recognized for their intricate vertical canopy stratification, exhibit high resistance to extreme drought. However, the response of leaf phenology to drought in the species-rich understory remains poorly understood. In this study, we constructed a digital camera system, amassing over 360,000 images through a 70% throughfall exclusion experiment, to explore the drought response of understory leaf phenology. The results revealed a significant advancement in understory leaf senescence phenology under drought, with 11.75 and 15.76 days for the start and end of the leaf-falling event, respectively. Pre-season temperature primarily regulated leaf development phenology, whereas soil water dominated the variability in leaf senescence phenology. Under drought conditions, temperature sensitivities for the end of leaf emergence decreased from -13.72 to -11.06 days °C-1, with insignificance observed for the start of leaf emergence. Consequently, drought treatment shortened both the length of the growing season (15.69 days) and the peak growth season (9.80 days) for understory plants. Moreover, this study identified diverse responses among intraspecies and interspecies to drought, particularly during the leaf development phase. These findings underscore the pivotal role of water availability in shaping understory phenology patterns, especially in subtropical forests.

Enhancing soil health and strawberry disease resistance: the impact of calcium cyanamide treatment on soil microbiota and physicochemical properties.

Introduction: Continuous strawberry cropping often causes soil-borne diseases, with 20 calcium cyanamide being an effective soil fumigant, pig manure can often be used as soil organic fertilizer. Its impact on soil microorganisms structure, however, remains unclear. Methods: This study investigated the effectiveness of calcium cyanamide and pig manure in treating strawberry soil, specifically against strawberry anthracnose. We examined the physical and chemical properties of the soil and the rhizosphere microbiome and performed a network analysis. Results: Results showed that calcium cyanamide treatment significantly reduces the mortality rate of strawberry in seedling stage by reducing pathogen abundance, while increasing actinomycetes and Alphaproteobacteria during the harvest period. This treatment also enhanced bacterial network connectivity, measured by the average connectivity of each Operational Taxonomic Unit (OTU), surpassing other treatments. Moreover, calcium cyanamide notably raised the levels of organic matter, available potassium, and phosphorus in the soil-key factors for strawberry disease resistance and yield. Discussion: Overall, applying calcium cyanamide to soil used for continuous strawberry cultivation can effectively decrease anthracnose incidence. It may be by changing soil physical and chemical properties and enhancing bacterial network stability, thereby reducing the copy of anthracnose. This study highlights the dual benefit of calcium cyanamide in both disease control and soil nutrient enhancement, suggesting its potential as a valuable tool in sustainable strawberry farming.

Recruitment of beneficial cucumber rhizosphere microbes mediated by amino acid secretion induced by biocontrol Bacillus subtilis isolate 1JN2.

Introduction: At present, the use of beneficial microorganisms to control cucumber Fusarium wilt is a widely used method, and the rhizosphere microecological reset is one of the mechanisms involved. However, how biocontrol strains reshape cucumber rhizosphere microecology remains to be further studied. Methods: The composition changes of cucumber root exudates induced by biocontrol strain 1JN2, the microbial ecology of cucumber rhizosphere and the colonization ability of biocontrol strain 1JN2 in cucumber rhizosphere were analyzed through UHPLC-MS/MS analysis, Illumina high-throughput sequencing and SEM, respectively. Results: First, cucumber plants treated with biocontrol Bacillus 1JN2 reduced the disease severity of Fusarium wilt by 60%. Significant changes in cucumber root exudates were found after 1JN2 inoculation and the contents of four amino acids including glutamine, tryptophan, glycine and glutamic acid were significantly increased. Second, It was found that the bacterial diversity in the rhizosphere of cucumber was significantly increased in both the strain treatment group and the amino acid mixture treatment group, The number of Bacillus was the largest in all dominant populations, exceeded 20% in all treatment groups. The bacteria of Hydrogenispora and Vicinamibacteria were significantly increased after treatment. Discussion: Overall, the results demonstrated that amino acid substances in cucumber root exudates induced by biocontrol strain 1JN2 can shift the cucumber root microenvironment and prevent the occurrence of Fusarium wilt disease.

The potential molecular mechanism underlying gypenoside amelioration of atherosclerosis in ApoE-/- mice: A multi-omics investigation.

Gypenosides (Gyp) are bioactive components of Gynostemma pentaphyllum that have a variety of pharmacological properties. Extracts of G. pentaphyllum have been found to be effective in the reduction of blood sugar and lipids and prevention of atherosclerosis. Here, the functions of Gyp and the mechanisms underlying their effects on atherosclerosis were investigated. Mice were allocated to three groups, namely, the control (C57BL/6), atherosclerosis model (ApoE-/- mice with high-fat diet), and Gyp-treated groups. Differentially expressed mRNAs, miRNAs, circRNA, and differential metabolites among the groups were analyzed. The results showed that "Fatty acid metabolism", "Fatty acid elongation", "Cytokine-cytokine receptor interaction", and "PI3K-Akt signaling pathway", amongst others, were involved in treatment process. Differentially expressed genes, including Fabp1, Apoe, FADS1, ADH1, SYNPO2, and Lmod1were also identified. Mmu-miR-30a and mmu-miR-30e showed reduced expression in atherosclerosis models but were increased following Gyp treatment, suggesting involvement in the effects of Gyp. In addition, chr5:150604177-150608440 were found to interact with mmu-miR-30a and mmu-miR-30e to regulate their abundance. In terms of metabolomics, Gyp may regulate biological processes involving PGD2 and PGJ2, potentially alleviating atherosclerosis. In conclusion, Gyp appeared to have complex effects on atherosclerosis, most of which were positive. These results support the use of Gyp in the treatment of atherosclerosis.

P-tau217 correlates with neurodegeneration in Alzheimer's disease, and targeting p-tau217 with immunotherapy ameliorates murine tauopathy.

Neuronal loss is the central issue in Alzheimer's disease (AD), yet no treatment developed so far can halt AD-associated neurodegeneration. Here, we developed a monoclonal antibody (mAb2A7) against 217 site-phosphorylated human tau (p-tau217) and observed that p-tau217 levels positively correlated with brain atrophy and cognitive impairment in AD patients. Intranasal administration efficiently delivered mAb2A7 into male PS19 tauopathic mouse brain with target engagement and reduced tau pathology/aggregation with little effect on total soluble tau. Further, mAb2A7 treatment blocked apoptosis-associated neuronal loss and brain atrophy, reversed cognitive deficits, and improved motor function in male tauopathic mice. Proteomic analysis revealed that mAb2A7 treatment reversed alterations mainly in proteins associated with synaptic functions observed in murine tauopathy and AD brain. An antibody (13G4) targeting total tau also attenuated tau-associated pathology and neurodegeneration but impaired the motor function of male tauopathic mice. These results implicate p-tau217 as a potential therapeutic target for AD-associated neurodegeneration.

Bifunctional iRGD-Exo-DOX crosses the blood-brain barrier to target central nervous system lymphoma.

Central nervous system lymphoma (CNSL) is a type of hematological tumor. Treatment of CNSL is difficult due to the existence of the blood-brain barrier (BBB). Here, we used exosomes (Exos), a type of extracellular vesicle, and iRGD to construct a new drug carrier system and use it to load doxorubicin (DOX). The results of in vitro and in vivo experiments showed that the iRGD-Exo-DOX system can efficiently and securely transport DOX through the BBB and target tumor cells. The results suggest that iRGD-Exo-DOX may cross the BBB through brain microvascular endothelial cell-mediated endocytosis. Together, our study indicates an impactful treatment of central nervous system tumors.

Spontaneous multivessel coronary artery spasm: a case report.

A 60-year-old male presented to the emergency department of our hospital with persistent dull pain in the lower and middle sternum with generalized sweating after a heated argument with another person, and his symptoms did not resolve after 3 hours of onset.

Comparing the effects of pulsed and radiofrequency catheter ablation on quality of life, anxiety, and depression of patients with paroxysmal supraventricular tachycardia: a single-center, randomized, single-blind, standard-controlled trial.

BACKGROUND: Radiofrequency catheter ablation (RFCA) may lead to decreased quality of life (QOL) and increased anxiety and depression in patients with paroxysmal supraventricular tachycardia (PSVT), possibly due to the lack of selectivity of the ablation tissue and the long ablation time. In recent years, pulsed field ablation (PFA) has been used for the first time in China to treat PSVT patients because of its ability to ablate abnormal tissue sites in a precise and transient manner. This study was conducted to compare the effects of PFA and RFCA on QOL and psychological symptoms of PSVT patients. METHODS: We have designed a single-center, randomized, single-blind, standard-controlled trial. A total of 50 participants who met the eligibility criteria would be randomly allocated into the PFA group or RFCA group in a 1:1 ratio. All participants were assessed using the 36-Item Short-Form Health Survey (SF-36) and the Hospital Anxiety and Depression Scale (HADS) at pre-procedure (T0), post-procedure (T1), and 3 months post-procedure (T2). The SPSS 21.0 software was used to analyze the data through Wilcoxon and Fisher's exact tests and repeated measures ANOVA. RESULTS: Twenty-five in the PFA group and 24 in the RFCA group completed the trial. SF-36: (1) Between-group comparison: At T1, PFA group had significantly higher SF-36 scores on physiological function (PF) and general health (GH) than RFCA group, with a treatment difference of 5.61 points and 18.51 points(P < 0.05). (2) Within-group comparison: We found that in the PFA and RFCA groups, T2 showed significant improvement in the remaining 6 subscales of the SF-36 scale compared to T1 and T0 (P < 0.05), except for body pain (BP) and social function (SF) scores. HADS: (1) Between-group comparison: no significant difference (P > 0.05). (2) Within-group comparison: The HADS scores of the PFA and RFCA groups were statistically significant at T2 compared to T0 and T1 (P < 0.05). CONCLUSIONS: Our study provided new and meaningful evidence that PFA was effective in significantly improving QOL and decreasing anxiety and depression in PFA patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2200060272.

Nutritional knowledge, attitudes, and practices among residents in the Northeast areas of China during the COVID-19 epidemic.

Background: The coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 infection continues to affect the daily life of communities worldwide. Nutrition is a vital determinant of overall health. Given the lack of specific drugs for COVID-19 and incomplete vaccination coverage, optimizing nutrition appears to be one of the most cost-effective means of enhancing immunity. Therefore, this study was designed to evaluate nutrition-related knowledge, attitudes, and practices (KAP) to offer insights into the personal determinants of dietary behavior during COVID-19 pandemic in four major cities within the Northeast region. Methods: This cross-sectional study was conducted between January and December 2022 using a self-administered questionnaire. The data were entered in EpiData V-3.02 and analyzed using SPSS version 26. Binary logistic regression analysis was also employed to examine the association between dependent and independent variables. Results: A total of 4,092 respondents were included in the study. Most of the respondents demonstrated had inadequate nutrition knowledge, 26% of them provided ≥60% of correct answers. About one-third of the respondents were knowledgeable about the daily levels of oil, salt, milk, water, vegetables and fruits for adults. Furthermore, our results showed that 60.6% of participants held positive attitudes toward healthy eating. Additionally, only 54.6% of the participants have heathy dietary practices during COVID-19 pandemic. Binary logistic regression analysis showed that the following characteristics were associated with displaying unhealthy dietary behaviors: being men, having a lower education level, having a family income of 10,000-19,999 and more than 20,000, being resided in Harbin, Shenyang, and Changchun. Importantly, the strongest associations were observed between poor dietary knowledge and unhealthy eating behaviors. Similarly, dietary attitudes were strongly associated with healthy dietary behaviors when the effects of other factors were excluded; responders with negative attitudes were more likely to exhibit unhealthy eating behaviors. Conclusion: Our findings suggest that residents in the Northeast China possessed a relatively low level of nutritional knowledge, which directly influenced their dietary practices during the COVID-19 pandemic. This study provides valuable insights into the cross-sectional description and key factors related to nutrition-related KAP, serving as a basis for future policymaking to respond more effectively to health crises.

A potential role for inflammatory cytokines in a rare late-onset capsular block syndrome: a case report.

BACKGROUND: Late-onset capsule block syndrome (CBS) is a rare complication of cataract phacoemulsification and the implantation of a posterior chamber intraocular lens (PCIOL), which manifests six months to years after surgery. The hallmark of CBS is the formation of an opaque liquid substance between the implanted intraocular lens (IOL) and the posterior capsule. However, its pathogenesis remains unclear. CASE PRESENTATION: A 64-year-old female patient with chronic angle-closure glaucoma (axis length < 21 mm) underwent trabeculectomy surgery combined with phacoemulsification and PCIOL. After a 4-year follow-up, a decline in visual acuity occurred in her right eye due to the location of opaque fluid in the visual axis and distension of the capsular bag. The initial course of action was to release the trapped fluid. Neodymium: yttrium-aluminum-garnet (Nd: YAG) laser capsulotomy could not be employed due to her non-dilating pupil and high extension of the posterior capsule. Subsequently, anterior capsule peeling and anterior segment vitrectomy surgery were performed. The depth of the anterior chamber (ACD), the distance between the face of the retro-IOL and the posterior capsule, the best-corrected visual acuity (BCVA), and the visual quality (VQ) were measured both before and after surgery. Inflammatory cytokine levels in the opaque substances (OS) trapped between the PCIOL and the posterior capsule were assessed using a flow cytometer and compared to normal statistical data in aqueous humor. After surgery, the patient experienced a significant improvement in BCVA and VQ. The distance between the face of the retro-IOL and the posterior capsule was on the verge of disappearing. However, ACD did not differ between pre- and post-operatively. Interleukin-8 (IL-8) and basic fibroblast growth factor (BFGF) concentrations were higher in the OS than in aqueous humor, especially in the former. However, the concentration of vascular cell adhesion molecule (VCAM) in the OS was lower than in aqueous humor. CONCLUSIONS: Anterior segment vitrectomy surgery proved to be a successful treatment for late-onset CBS, presenting a challenging case. In the human lens, inflammatory cytokines originating from the opaque substances may contribute to abnormal metabolism in the sealed area, a consequence of late-onset CBS.

Identification of a novel fusion gene, RARA::ANKRD34C, in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a specific subtype of acute myeloid leukemia that is distinguished by the chromosomal translocation t(15;17)(q24;q21), which leads to the fusion of the promyelocytic leukemia (PML) gene with the retinoic acid receptor alpha (RARA). Recently, we identified a novel fusion gene in APL, RARA::ankyrin repeat domain 34C (ANKRD34C), identified its functions by morphological, cytogenetic, molecular biological and multiplex fluorescence in situ hybridization analyses, and demonstrated the potential therapeutic effect clinically and experimentally of all-trans retinoic acid (ATRA); the findings have important implications for the diagnosis and treatment of atypical APL.

Application of dirty-acid wastewater treatment technology in non-ferrous metal smelting industry: Retrospect and prospect.

Dirty-acid wastewater (DW) originating from the non-ferrous metal smelting industry is characterized by a high concentration of H2SO4 and As. During the chemical precipitation treatment, a significant volume of arsenic-containing slag is generated, leading to elevated treatment expenses. The imperative to address DW with methods that are cost-effective, highly efficient, and safe is underscored. This paper conducts a comprehensive analysis of three typical methods to DW treatment, encompassing technical principles, industrial application flow charts, research advancements, arsenic residual treatment, and economic considerations. Notably, the sulfide method emerges as a focal point due to its minimal production of arsenic residue and the associated lowest overall treatment costs. Moreover, in response to increasingly stringent environmental protection policies targeting new pollutants and carbon emissions reduction, the paper explores the evolving trends in DW treatment. These trends encompass rare metal and sulfuric acid recycling, cost-effective H2S production methods, and strategies for reducing, safely disposing of, and harnessing resources from arsenic residue.

Enantioselective Synthesis of Biphenyl-Bridged ϵ-Sultams by Organocatalytic Mannich Reactions of Cyclic N-Sulfonylimines with Unactivated Ketones.

A highly enantioselective Mannich reaction of biphenyl-bridged seven-membered cyclic N-sulfonylimines with methyl alkyl ketones is disclosed in this study. The reaction was performed under organocatalysis by using a quinine-derived primary amine as the catalyst in combination with a Brønsted acid as the co-catalyst. High yields (up to 89 %) and excellent enantioselectivities (up to 97 % ee) were observed. For methyl alkyl ketones containing a larger alkyl substituent, specific regioselective addition to the C=N bond is favored at the methyl group. On the contrary, ketones containing a smaller alkyl substituent or hydroxyacetone substrates gave major syn selective Mannich products at the methylene group.