Cyclobutanes

环丁烷
  • 文章类型: Journal Article
    应变碳环结构单元的合成与药物化学有关,和亚甲基环丁烷在当前的合成技术中尤其具有挑战性。仔细检查[1.1.1]推进剂和二硼试剂的反应性,发现双(儿茶酚)二硼(B2cat2)可以在室温下在几分钟内产生双(硼化)亚甲基环丁烷。该反应构成了通过特殊的非极性烃活化B-B键的第一个例子,也是第一次用硼亲电活化推进剂。包括原位NMR动力学和DFT计算在内的机理研究表明,二硼部分可以通过与推进剂的倒σ键配位而直接活化。并揭示DMF参与二硼酸酯中间体的稳定而不是B-B键的活化。这些结果为二硼和推进剂化学提供了新的可能性,并进一步发展了基于推进剂菌株释放的亚甲基环丁烷的合成。
    The synthesis of strained carbocyclic building blocks is relevant for Medicinal Chemistry, and methylenecyclobutanes are particularly challenging with current synthetic technology. Careful inspection of the reactivity of [1.1.1]propellane and diboron reagents has revealed that bis(catecholato)diboron (B2cat2) can produce a bis(borylated) methylenecyclobutane in a few minutes at room temperature. This reaction constitutes the first example of B-B bond activation by a special apolar hydrocarbon and also the first time that propellane is electrophilically activated by boron. Mechanistic studies including in situ NMR kinetics and DFT calculations demonstrate that the diboron moiety can be directly activated through coordination with the inverted sigma bond of propellane, and reveal that DMF is involved in the stabilization of diboronate ylide intermediates rather than the activation of the B-B bond. These results enable new possibilities for both diboron and propellane chemistry, and for further developments in the synthesis of methylenecyclobutanes based on propellane strain release.
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  • 文章类型: Journal Article
    固态的构象在结晶过程中通常是固定的。3,5-双((E)-2-(吡啶-4-基)乙烯基)甲基苯(CH3-3,5-bpeb)中的“冷冻”C=C构象的转移通过光二聚选择性产生环丁烷和二环丁烷异构体,其中一种(异构体2)对T-24、7402、MGC803、HepG-2和HeLa细胞表现出优异的体外抗癌活性。
    Conformations in the solid state are typically fixed during crystallization. Transference of \"frozen\" C=C conformations in 3,5-bis((E)-2-(pyridin-4-yl)vinyl)methylbenzene (CH3-3,5-bpeb) by photodimerization selectively yielded cyclobutane and dicyclobutane isomers, one of which (Isomer 2) exhibited excellent in vitro anti-cancer activity towards T-24, 7402, MGC803, HepG-2, and HeLa cells.
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  • 文章类型: Journal Article
    环加成反应在直接组装环结构的合成化学中起着关键作用。然而,通过可编程的[4n]环加成延伸C4合成子构建不同的杂环仍然存在障碍。在这里,我们报告了使用呋喃稠合的环丁酮(FCB)作为通用C4合成子的原子经济和模块化分子间环加成。与文献记载的苯并环丁烯酮的环加成相反,这是使用FCB作为C4试剂的补充版本。它涉及C-C键活化和环加成序列,包括Rh催化的与亚胺的对映选择性[42]-环加成和Au催化的与蒽醌的非对映选择性[44]-环加成。获得的呋喃稠合内酰胺,这是许多天然产品中存在的关键图案,生物活性分子,和材料,用其他方法难以接近或难以准备。初步抗肿瘤活性研究表明,6e和6f对结肠癌细胞(HCT-116,IC50=0.50±0.05μM)和食管鳞状细胞癌细胞(KYSE-520,IC50=0.89±0.13μM)具有较高的抗癌效力,分别。
    Cycloaddition reactions play a pivotal role in synthetic chemistry for the direct assembly of cyclic architectures. However, hurdles remain for extending the C4 synthon to construct diverse heterocycles via programmable [4+n]-cycloaddition. Here we report an atom-economic and modular intermolecular cycloaddition using furan-fused cyclobutanones (FCBs) as a versatile C4 synthon. In contrast to the well-documented cycloaddition of benzocyclobutenones, this is a complementary version using FCB as a C4 reagent. It involves a C-C bond activation and cycloaddition sequence, including a Rh-catalyzed enantioselective [4 + 2]-cycloaddition with imines and an Au-catalyzed diastereoselective [4 + 4]-cycloaddition with anthranils. The obtained furan-fused lactams, which are pivotal motifs that present in many natural products, bioactive molecules, and materials, are inaccessible or difficult to prepare by other methods. Preliminary antitumor activity study indicates that 6e and 6 f exhibit high anticancer potency against colon cancer cells (HCT-116, IC50 = 0.50 ± 0.05 μM) and esophageal squamous cell carcinoma cells (KYSE-520, IC50 =  0.89 ± 0.13 μM), respectively.
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  • 文章类型: Journal Article
    癌细胞从血液中招募中性粒细胞进入肿瘤组织,这些免疫细胞促进许多实体瘤的进展。在小鼠中的研究表明,通过抑制中性粒细胞趋化因子受体CXCR2阻断中性粒细胞募集到肿瘤可能是胰腺癌的潜在免疫疗法。然而,中性粒细胞促进人类肿瘤进展的机制,以及CXCR2抑制如何可能作为癌症治疗,仍然难以捉摸。在这项研究中,我们开发了一种基于人类细胞的微生理系统,以量化中性粒细胞-肿瘤球体在“分离”和“接触”两种情况下的相互作用。我们发现中性粒细胞通过分泌可溶性因子和与癌细胞直接接触促进肿瘤球体的侵袭。然而,它们仅通过直接接触促进肿瘤球体的增殖。有趣的是,用CXCR2抑制剂AZD-5069治疗,通过阻断与中性粒细胞的直接接触来减弱肿瘤球体的侵袭和增殖。我们的发现还表明,CXCR2抑制减少了嗜中性粒细胞向肿瘤球体的迁移。这些结果为人类中性粒细胞的肿瘤促进机制和胰腺癌中CXCR2抑制的肿瘤抑制机制提供了新的思路,并可能有助于设计和优化基于中性粒细胞的新型免疫治疗策略。
    Cancer cells recruit neutrophils from the bloodstream into the tumor tissue, where these immune cells promote the progression of numerous solid tumors. Studies in mice suggest that blocking neutrophil recruitment to tumors by inhibition of neutrophil chemokine receptor CXCR2 could be a potential immunotherapy for pancreatic cancer. Yet, the mechanisms by which neutrophils promote tumor progression in humans, as well as how CXCR2 inhibition could potentially serve as a cancer therapy, remain elusive. In this study, we developed a human cell-based microphysiological system to quantify neutrophil-tumor spheroid interactions in both \"separated\" and \"contact\" scenarios. We found that neutrophils promote the invasion of tumor spheroids through the secretion of soluble factors and direct contact with cancer cells. However, they promote the proliferation of tumor spheroids solely through direct contact. Interestingly, treatment with AZD-5069, a CXCR2 inhibitor, attenuates invasion and proliferation of tumor spheroids by blocking direct contact with neutrophils. Our findings also show that CXCR2 inhibition reduces neutrophil migration toward tumor spheroids. These results shed new light on the tumor-promoting mechanisms of human neutrophils and the tumor-suppressive mechanisms of CXCR2 inhibition in pancreatic cancer and may aid in the design and optimization of novel immunotherapeutic strategies based on neutrophils.
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  • 文章类型: Journal Article
    背景:先前的研究表明,新辅助化疗(NAC)中添加铂类药物可改善三阴性乳腺癌(TNBC)患者的预后。然而,尚无研究评估紫杉烷和洛铂联合用药的疗效和安全性.在这项研究中,我们进行了一项随机对照II期临床研究,以比较紫杉烷联合洛铂或蒽环类药物的疗效和安全性.
    方法:我们将I-III期TNBC患者随机分为A组和B组。B组接受了六个周期的紫杉烷与蒽环类和环磷酰胺(TEC)的组合,或八个周期的蒽环类和环磷酰胺的组合,并连续使用紫杉烷(EC-T)。两个手臂都在NAC后接受了手术。主要终点是病理完全缓解(pCR)。次要终点是无事件生存期(EFS),总生存期(OS),和安全。
    结果:共评估了103例患者(A组51例,B组52例)。A臂的pCR率明显高于B臂(41.2%vs.21.2%,P=0.028)。淋巴结阳性和中性粒细胞与淋巴细胞比率(NLR)低的患者比淋巴结阴性和NLR高的患者从A组中受益更多(分别为P交互作用=0.001,P交互作用=0.012)。两组之间的EFS(P=0.895)或OS(P=0.633)没有显着差异。A组3/4级贫血患病率较高(P=0.015),B组3/4级中性粒细胞减少症患病率较高(P=0.044).
    结论:新佐剂紫杉烷联合洛铂的疗效优于紫杉烷联合蒽环类,两种方案的毒性特征相似.该试验可能为今后NAC治疗TNBC的更好的联合免疫治疗策略提供参考。
    BACKGROUND: Previous studies have shown that the addition of platinum to neoadjuvant chemotherapy (NAC) improved outcomes for patients with triple-negative breast cancer (TNBC). However, no studies have assessed the efficacy and safety of the combination of taxane and lobaplatin. In this study, we conducted a randomized controlled phase II clinical study to compare the efficacy and safety of taxane combined with lobaplatin or anthracycline.
    METHODS: We randomly allocated patients with stage I-III TNBC into Arm A and Arm B. Arm A received six cycles of taxane combined with lobaplatin (TL). Arm B received six cycles of taxane combined with anthracycline and cyclophosphamide (TEC) or eight cycles of anthracycline combined with cyclophosphamide and sequential use of taxane (EC-T). Both Arms underwent surgery after NAC. The primary endpoint was the pathologic complete response (pCR). Secondary endpoints were event-free survival (EFS), overall survival (OS), and safety.
    RESULTS: A total of 103 patients (51 in Arm A and 52 in Arm B) were assessed. The pCR rate of Arm A was significantly higher than that of Arm B (41.2% vs. 21.2%, P = 0.028). Patients with positive lymph nodes and low neutrophil-to-lymphocyte ratio (NLR) benefited significantly more from Arm A than those with negative lymph nodes and high NLR (Pinteraction = 0.001, Pinteraction = 0.012, respectively). There was no significant difference in EFS (P = 0.895) or OS (P = 0.633) between the two arms. The prevalence of grade-3/4 anemia was higher in Arm A (P = 0.015), and the prevalence of grade-3/4 neutropenia was higher in Arm B (P = 0.044).
    CONCLUSIONS: Neoadjuvant taxane plus lobaplatin has shown better efficacy than taxane plus anthracycline, and both regimens have similar toxicity profiles. This trial may provide a reference for a better combination strategy of immunotherapy in NAC for TNBC in the future.
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  • 文章类型: Journal Article
    全氟环丁烷(c-C4F8,PFC-318)的全球大气排放,一种强大的温室气体,近年来增长迅速。将中国9个站点的大气观测与基于拉格朗日色散模型的贝叶斯反演技术相结合,我们显示,中国的PFC-318排放量从2011年到2020年增长了约70%,从2011年的0.65(0.54-0.72)Ggyear-1上升到2020年的1.12(1.05-1.19)Ggyear-1。在研究期间,中国的PFC-318排放增加对全球排放的总体增长起到了重要作用,对全球排放总量增长贡献58%。这种增长主要起源于中国东部。中国PFC-318排放高的地区与聚四氟乙烯(PTFE)工厂密集的地区重叠,这意味着含氟聚合物工厂是中国PFC-318排放的重要来源。我们的调查显示,如果我们假设在中国生产的所有用于原料的HCFC-22都被热解以生产PTFE和HFP,则在生产四氟乙烯(TFE)和六氟丙烯(HFP)中,每千克使用的氢氯氟烃-22(HCFC-22)原料的排放因子约为3.02g。需要进一步的设施级采样和分析,以便更精确地评估这些工厂的排放。
    Global atmospheric emissions of perfluorocyclobutane (c-C4F8, PFC-318), a potent greenhouse gas, have increased rapidly in recent years. Combining atmospheric observations made at nine Chinese sites with a Lagrangian dispersion model-based Bayesian inversion technique, we show that PFC-318 emissions in China grew by approximately 70% from 2011 to 2020, rising from 0.65 (0.54-0.72) Gg year-1 in 2011 to 1.12 (1.05-1.19) Gg year-1 in 2020. The PFC-318 emission increase from China played a substantial role in the overall increase in global emissions during the study period, contributing 58% to the global total emission increase. This growth predominantly originated in eastern China. The regions with high emissions of PFC-318 in China overlap with areas densely populated with polytetrafluoroethylene (PTFE) factories, implying that fluoropolymer factories are important sources of PFC-318 emissions in China. Our investigation reveals an emission factor of approximately 3.02 g of byproduct PFC-318 emissions per kg of hydrochlorofluorocarbon-22 (HCFC-22) feedstock use in the production of tetrafluoroethylene (TFE) (for PTFE production) and hexafluoropropylene (HFP) if we assume all HCFC-22 produced for feedstock uses in China are pyrolyzed to produce PTFE and HFP. Further facility-level sampling and analysis are needed for a more precise evaluation of emissions from these factories.
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  • 文章类型: Journal Article
    甲基对硫磷,剧毒,高效,和持久性有机磷农药,在中国广泛使用。西布曲明,一种非苯丙胺中枢神经系统抑制剂,通过破坏激素调节来帮助减肥,刺激交感神经,抑制食欲。然而,一些不道德的企业未能正确处理苹果醋等食品中的原材料,导致苹果中残留甲基对硫磷或非法过量添加西布曲明。因此,必须开发一种快速检测甲基对硫磷和西布曲明的免疫分析方法。根据甲基对硫磷-硫-牛血清蛋白(BSA)/鸡卵清蛋白(OVA)-西布曲明(20:1:过量,15:1:超额,10:1:超额,和5:1:超额),和西布曲明-BSA/OVA-甲基对硫磷(20:1:过量,10:1:超额:5:1:超额,和0:1:超额)。结果表明,甲基对硫磷-BSA/OVA-西布曲明(20:1:过量)抗体的抑制率高于西布曲明-BSA/OVA-甲基对硫磷,67.93%,在此抑制率下,甲基对硫磷的浓度为8.65ngmL-1。因此,选择甲基对硫磷-BSA/OVA-西布曲明(8.65:1:过量)和相应的抗体用于随后的方法建立。通过改变涂层和抗体的浓度,当涂层为0.125ngmL-1,抗体稀释4000倍时,发现抑制率。该抗体用于建立标准曲线,用于检测西布曲明的半数最大抑制浓度(IC50)为4.59ngmL-1,检测限(IC10)为2.21ngmL-1,检测范围为2.89至7.28ngmL-1,甲基对磷的半数最大抑制浓度(IC50)为15.34ngmL-1,检测限(IC10)为0.42ng-1mL。在这些条件下,回收率在88%到102%之间,在合理的范围内,表明成功建立了快速酶联ELISA检测方法。
    Methyl parathion, a highly toxic, efficient, and persistent organophosphorus pesticide, is widely used in China. Sibutramine, a non-amphetamine central nervous system depressant, helps lose weight by disrupting hormone regulation, stimulating sympathetic nerves, and suppressing appetite. However, some unethical businesses fail to properly handle raw materials in foods like apple cider vinegar, leading to residual methyl parathion in apples or illegal excessive addition of sibutramine. Therefore, it is imperative to develop an immunoassay for the rapid detection of methyl parathion and sibutramine. The corresponding two haptens were prepared and coupled with the carrier proteins according to methyl parathion-sulfur-bovine serum protein (BSA)/chicken ovalbumin (OVA)-sibutramine (20 : 1 : excess, 15 : 1 : excess, 10 : 1 : excess, and 5 : 1 : excess), and sibutramine-BSA/OVA-methyl parathion (20 : 1 : excess, 10 : 1 : excess: 5 : 1 : excess, and 0 : 1 : excess). The result shows that the inhibition rate of the antibody obtained by methyl parathion-BSA/OVA-sibutramine (20 : 1 : excess) was higher than that of sibutramine-BSA/OVA-methyl parathion, which was 67.93%, and the concentration of methyl parathion was 8.65 ng mL-1 at this inhibition rate. Thus, methyl parathion-BSA/OVA-sibutramine (8.65 : 1 : excess) and the corresponding antibodies were selected for subsequent method establishment. By changing the concentration of the coating and antibody, the inhibition rate was found when the coating was 0.125 ng mL-1 and the antibody was diluted 4000 times. The antibody was used to develop a standard curve for the detection of sibutramine at the half-maximum inhibitory concentration (IC50) is 4.59 ng mL-1, the limit of detection (IC10) is 2.21 ng mL-1, the detection range is 2.89 to 7.28 ng mL-1, methyl p-phosphorus at the half-maximum inhibitory concentration (IC50) is 15.34 ng mL-1, the limit of detection (IC10) is 0.42 ng mL-1, the detection range is ng mL-1. Under these conditions, the recovery rate was between 88% and 102%, within reasonable limits, indicating the successful establishment of a rapid enzyme-linked ELISA assay.
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  • 文章类型: Journal Article
    本文报道了炔烃和丙烯酸酯之间的第一Ficini反应。该反应由作为路易斯酸的B(C6F5)3催化,并以高产率获得稳定的三取代氨基环丁烯。所得产物可以在碱性条件下或在路易斯酸存在下进行氢化和差向异构化,以高产率和非对映异构体比例(高达定量产率和>99:1dr)提供两种不同的转氨基环丁烷单酯立体异构体。
    The first Ficini reaction between ynamides and acrylates is reported herein. The reaction is catalyzed by B(C6F5)3 acting as a Lewis acid and is giving access to stable tri-substituted aminocyclobutenes in high yield. The resulting products can be hydrogenated and epimerized under basic conditions or in presence of a Lewis acid, providing two distinct trans- aminocyclobutane monoester stereoisomers in high yield and diastereoisomeric ratio (up to quantitative yield and >99:1 dr).
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  • 文章类型: Journal Article
    由于报告基因相关可见/NIR-I生物发光成像的广泛应用,跨可见光/NIR-I/NIR-II的多路荧光成像在生物医学研究中具有出色的潜力。然而,由于缺乏适当的荧光团,在这些区域的体内多路成像应用很少有报道。在这里,九种方酸染料,表现出不同的吸附和发射波长,是合成的。其中,发现水溶性SQ710-5k和SQ905具有显着的吸收差异,这使得肿瘤和淋巴结得以识别。然后,第一次,通过与报告基因相关的生物发光荧光粉协调,实现了可见光/NIR-I/II的六通道多重荧光成像。其他研究表明,SQ710-5k在NIR-II中表现出更高质量的血管和肿瘤成像。H-聚集体SQ905表现出用于光热治疗的高光热转换效率。这项研究提出了一种方法来创建与报告基因相关的生物发光磷光体协调的小分子染料,用于六色荧光成像。
    Due to the wide application of reporter gene-related visible/NIR-I bioluminescent imaging, multiplexed fluorescence imaging across visible/NIR-I/NIR-II has excellent potential in biomedical research. However, in vivo multiplexed imaging applications across those regions have rarely been reported due to the lack of proper fluorophores. Herein, nine squaraine dyes, which exhibit diverse adsorption and emission wavelengths, were synthesized. Among them, water-soluble SQ 710-5k and SQ 905 were found to have significant absorption differences, which allowed the tumor and lymph nodes to be identified. Then, for the first time, six-channel multiplexed fluorescence imaging across visible/NIR-I/II was achieved by coordination with reporter gene-related bioluminescent phosphors. Additional research revealed that SQ 710-5k exhibited higher-quality blood vessels and tumor imaging in NIR-II. H-aggregates SQ 905 demonstrated a high photothermal conversion efficiency for photothermal therapy. This study proposed an approach to creating small molecular dyes that coordinate with reporter gene-related bioluminescent phosphors for six-color fluorescence imaging.
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  • 文章类型: Journal Article
    背景:我们的目的是比较7种新的免疫疗法和靶向疗法治疗铂耐药的复发性卵巢癌。
    方法:我们对PubMed进行了全面搜索,EMBASE,和CochraneLibrary电子数据库,用于涉及接受免疫治疗或靶向治疗联合化疗治疗的铂耐药复发性卵巢癌(PRrOC)患者的III期试验。使用GRADE方法评估纳入试验的质量。比较的主要结果是无进展生存期,次要结局包括总生存率和安全性.
    结果:本分析包括7项III期随机对照试验,包括2485名PRrOC患者。与所有其他感兴趣的方案相比,贝伐单抗联合化疗和lurbinectedin在无进展生存期方面表现出统计学上的显着差异。然而,总生存期无统计学差异.Nivolumab和mirvetuximab表现出比其他感兴趣的方案更少的严重不良事件。
    结论:我们的研究结果表明,贝伐单抗联合化疗和lurbinectedin单药治疗PRrOC患者具有显著疗效。对于已经用尽治疗方案的PRrOC患者,由于nivolumab和mirvetuximab具有更好的安全性,因此可以考虑作为替代方案.
    BACKGROUND: We aimed to compare 7 newer immunotherapies and targeted therapies for platinum-resistant relapsed ovarian cancer.
    METHODS: We conducted a comprehensive search of PubMed, EMBASE, and Cochrane Library electronic databases for phase III trials involving platinum-resistant recurrent ovarian cancer (PRrOC) patients treated with immunotherapy or targeted therapy in combination with chemotherapy. The quality of the included trials was assessed using the GRADE method. The primary outcome of comparison was progression-free survival, and secondary outcomes included overall survival and safety.
    RESULTS: This analysis included 7 randomized phase III controlled trials, encompassing 2485 PRrOC patients. Combining bevacizumab plus chemotherapy and lurbinectedin demonstrated statistically significant differences in progression-free survival compared to all other regimens of interest. However, no statistically significant differences were observed in the overall survival. Nivolumab and mirvetuximab exhibited fewer serious adverse events than the other regimens of interest.
    CONCLUSIONS: Our findings indicate that bevacizumab combined with chemotherapy and lurbinectedin monotherapy has significant efficacy in patients with PRrOC. For patients with PRrOC who have exhausted treatment options, nivolumab and mirvetuximab may be considered as alternatives because of their better safety profiles.
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