Cyclobutanes

环丁烷
  • 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
    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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  • 文章类型: Journal Article
    背景:通过前列腺特异性抗原(PSA)评估和常规成像,无法在转移性去势抵抗性前列腺癌(mCRPC)中早期识别对雄激素受体靶向药物(ARTA)有反应和耐药的患者。考虑到其确定病变代谢活动的能力,正电子发射断层扫描(PET)评估可能是一个有前途的工具。
    方法:我们在接受ARTA治疗的mCRPC患者中进行了一项单中心前瞻性研究,以评估不同PET放射性示踪剂的作用:49例患者随机接受11C-胆碱,氟18氟虫(抗-1-氨基-3-18F-氟环丁烷-1-羧酸-FACBC)(18F-FACBC),或镓-68-前列腺特异性膜抗原(68Ga-PSMA)PET,治疗前和2个月后的一次扫描。主要目的是研究三种新型PET放射性示踪剂的性能,以早期评估转移性CRPC患者对ARTA的反应;评估的结果是生化反应(PSA降低≥50%)。次要目的是研究几种半定量PET参数的预后作用及其在生化无进展生存期(bPFS)和总生存期(OS)方面随不同放射性示踪剂的变化。该研究由意大利卫生部(代码RF-2016-02364809)推动。
    结果:关于主要终点,在对数秩检验中,在使用68Ga-PSMAPET和生化反应的两次扫描中,代谢性肿瘤体积(MTV)(P=0.018)和总病变活性(TLA)(P=0.025)百分比变化之间存在统计学显著相关性.至于次要终点,在第一次扫描时,68Ga-PSMA总MTV和TLA与bPFS显着相关(分别为P=0.001和P=0.025),和MTV百分比变异(P=0.031)。对于操作系统,在第一次11C-胆碱PET扫描中,对于不同的68Ga-PSMA和18F-FACBC参数以及主要的最大标准化摄取值,发现了统计学上的显着相关性。
    结论:我们的研究强调11C-胆碱,68Ga-PSMA,18F-FACBC半定量PET参数及其变化在OS和bPFS方面具有预后价值,MTV和TLA与68Ga-PSMAPET的变化与生化反应相关,这可以帮助评估对ARTA的反应。
    BACKGROUND: The early identification of responsive and resistant patients to androgen receptor-targeting agents (ARTA) in metastatic castration-resistant prostate cancer (mCRPC) is not completely possible with prostate-specific antigen (PSA) assessment and conventional imaging. Considering its ability to determine metabolic activity of lesions, positron emission tomography (PET) assessment might be a promising tool.
    METHODS: We carried out a monocentric prospective study in patients with mCRPC treated with ARTA to evaluate the role of different PET radiotracers: 49 patients were randomized to receive 11C-Choline, Fluorine 18 fluciclovine (anti-1-amino-3-18F-fluorocyclobutane-1-carboxylic acid - FACBC) (18F-FACBC), or Gallium-68-prostate-specific-membrane-antigen (68Ga-PSMA) PET, one scan before therapy and one 2 months later. The primary aim was to investigate the performance of three novel PET radiotracers for the early evaluation of response to ARTA in metastatic CRPC patients; the outcome evaluated was biochemical response (PSA reduction ≥50%). The secondary aim was to investigate the prognostic role of several semiquantitative PET parameters and their variations with the different radiotracers in terms of biochemical progression-free survival (bPFS) and overall survival (OS). The study was promoted by the Italian Department of Health (code RF-2016-02364809).
    RESULTS: Regarding the primary endpoint, at log-rank test a statistically significant correlation was found between metabolic tumor volume (MTV) (P = 0.018) and total lesion activity (TLA) (P = 0.025) percentage variation among the two scans with 68Ga-PSMA PET and biochemical response. As for the secondary endpoints, significant correlations with bPFS were found for 68Ga-PSMA total MTV and TLA at the first scan (P = 0.001 and P = 0.025, respectively), and MTV percentage variation (P = 0.031). For OS, statistically significant correlations were found for different 68Ga-PSMA and 18F-FACBC parameters and for major maximum standardized uptake value at the first 11C-Choline PET scan.
    CONCLUSIONS: Our study highlighted that 11C-Choline, 68Ga-PSMA, and 18F-FACBC semiquantitative PET parameters and their variations present a prognostic value in terms of OS and bPFS, and MTV and TLA variations with 68Ga-PSMA PET a correlation with biochemical response, which could help to assess the response to ARTA.
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  • 文章类型: Journal Article
    胰凝乳蛋白酶,人体消化中的关键酶,催化牛奶蛋白质的分解,强调其在健康诊断和乳制品质量保证方面的重要性。解决快速的迫切需要,具有成本效益的检测方法,我们引入了一种利用远红技术和HOMO-Förster共振能量转移(FRET)的开创性方法。我们新颖的探测器,SQ-122PC,具有独特的分子设计,包括方酸染料(SQ),一个肽接头,和通过固相肽合成合成的SQ部分。在定制的H2O:DMSO(7:3)溶剂系统中,显示出93.75%的显着淬灭效率,我们的探针在远红光谱中表现出吸收和发射特性,具有前所未有的检测限为0.130nM。重要的是,我们的方法对胰凝乳蛋白酶提供了无与伦比的选择性,确保可靠和准确的酶检测。这项开创性的工作强调了基于远红的同源FRET系统在实现胰凝乳蛋白酶活性的灵敏和特异性检测方面的巨大潜力。通过弥合尖端技术和生物医学诊断之间的差距,我们的发现预示着酶传感的新时代,疾病诊断和乳品质量控制方面有希望的变革性进步。
    Chymotrypsin, a crucial enzyme in human digestion, catalyzes the breakdown of milk proteins, underscoring its significance in both health diagnostics and dairy quality assurance. Addressing the critical need for rapid, cost-effective detection methods, we introduce a groundbreaking approach utilizing far-red technology and HOMO-Förster resonance energy transfer (FRET). Our novel probe, SQ-122 PC, features a unique molecular design that includes a squaraine dye (SQ), a peptide linker, and SQ moieties synthesized through solid-phase peptide synthesis. Demonstrating a remarkable quenching efficiency of 93.75% in a tailored H2O:DMSO (7:3) solvent system, our probe exhibits absorption and emission properties within the far-red spectrum, with an unprecedented detection limit of 0.130 nM. Importantly, our method offers unparalleled selectivity towards chymotrypsin, ensuring robust and accurate enzyme detection. This pioneering work underscores the immense potential of far-red-based homo-FRET systems in enabling the sensitive and specific detection of chymotrypsin enzyme activity. By bridging the gap between cutting-edge technology and biomedical diagnostics, our findings herald a new era of enzyme sensing, promising transformative advancements in disease diagnosis and dairy quality control.
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  • 文章类型: Journal Article
    已经做出了许多努力来开发用于癌症的NIR激光诱导光疗的高效近红外(NIR)荧光染料。然而,低肿瘤靶向性和体内非特异性组织对NIR染料的高摄取限制了其在临床前癌症成像和治疗中的应用。在各种近红外染料中,方酸(SQ)染料由于其高摩尔消光系数而被广泛使用,强烈的荧光,和优异的光稳定性。以前,苯并吲哚衍生的SQ(BSQ)通过将羧基戊基苯并吲哚末端基团掺入经典的SQ主链中来制备,然后与环状RGD肽缀合用于肿瘤靶向成像。在这项研究中,我们证明,结构固有的肿瘤靶向BSQ不仅在血清中显示出高荧光量子产率,而且在671nm激光照射下表现出优异的活性氧(ROS)生成能力,用于体外和体内有效的光动力疗法(PDT)。没有靶向配体,BSQ在注射后24小时优先积累在肿瘤组织中,这是激光照射诱导ROS产生增量的最佳时机。因此,这项工作为开发用于靶向癌症治疗的光动力治疗性SQ染料提供了有希望的策略。
    Many efforts have been made to develop near-infrared (NIR) fluorescent dyes with high efficiency for the NIR laser-induced phototherapy of cancer. However, the low tumor targetability and high nonspecific tissue uptake of NIR dyes in vivo limit their applications in preclinical cancer imaging and therapy. Among the various NIR dyes, squaraine (SQ) dyes are widely used due to their high molar extinction coefficient, intense fluorescence, and excellent photostability. Previously, benzoindole-derived SQ (BSQ) was prepared by incorporating carboxypentyl benzoindolium end groups into a classical SQ backbone, followed by conjugating with cyclic RGD peptides for tumor-targeted imaging. In this study, we demonstrate that the structure-inherent tumor-targeting BSQ not only shows a high fluorescence quantum yield in serum but also exhibits superior reactive oxygen species (ROS) generation capability under the 671 nm laser irradiation for effective photodynamic therapy (PDT) in vitro and in vivo. Without targeting ligands, the BSQ was preferentially accumulated in tumor tissue 24 h post-injection, which was the optimal timing of the laser irradiation to induce increments of ROS production. Therefore, this work provides a promising strategy for the development of photodynamic therapeutic SQ dyes for targeted cancer therapy.
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  • 文章类型: Journal Article
    背景:我们以前的工作表明,在紫杉烷和蒽环类联合治疗中添加洛铂可以提高三阴性乳腺癌(TNBC)新辅助治疗的病理完全缓解率,并延长长期生存率。但该方案的治疗标志物尚不清楚.
    方法:83名符合纳入标准的患者被纳入本事后分析。我们分析了新辅助化疗前血小板与淋巴细胞比值(PLR)和中性粒细胞与淋巴细胞比值(NLR)与多西他赛治疗后疗效和预后的关系。表柔比星,洛铂新辅助化疗方案。采用χ2检验和Cox回归分析PLR和NLR与病理完全缓解(tpCR)的关系,以及PLR和NLR与无事件生存率(EFS)和总生存率(OS)之间的关联,分别。
    结果:PLR组的tpCR率为49.0%(25/51),显著高于PLR+组(25.0%[8/32],P=.032)。NLR组的tpCR率为49.1%(26/53),显著高于NLR+组(23.3%[7/30],P=.024)。PLR-NLR-(PLR-和NLR-)组的tpCR率为53.7%(22/41),显著高于PLR+/NLR+(PLR+或/和NLR+)组(26.1%[11/42];P=.012)。NLR+组的EFS和OS明显短于NLR-组(EFS的P=0.028;OS的P=0.047)。PLR-NLR-组患者的EFS比PLR+/NLR+组患者长(P=0.002)。
    结论:PLR和NLR可用于预测紫杉烷新辅助治疗的疗效。蒽环类药物,和洛铂方案治疗TNBC患者,PLR和NLR值较低的患者tpCR率较高,长期预后较好.
    BACKGROUND: Our previous work indicated that the addition of lobaplatin to combined therapy with taxane and anthracycline can improve the pathological complete response rate of neoadjuvant therapy for triple-negative breast cancer (TNBC) and lengthen long-term survival significantly, but the therapeutic markers of this regimen are unclear.
    METHODS: Eighty-three patients who met the inclusion criteria were included in this post hoc analysis. We analyzed the association between platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) before neoadjuvant chemotherapy with the efficacy and prognosis after treatment with docetaxel, epirubicin, and lobaplatin neoadjuvant chemotherapy regimen. χ2 test and Cox regression were used to analyze the association between PLR and NLR with total pathologic complete response (tpCR), as well as the association between PLR and NLR with event-free survival (EFS) and overall survival (OS), respectively.
    RESULTS: The tpCR rate in the PLR- group was 49.0% (25/51), which was significantly higher than that in the PLR+ group (25.0% [8/32], P = .032). The tpCR rate in the NLR- group was 49.1% (26/53), which was significantly higher than that in the NLR+ group (23.3% [7/30], P = .024). The tpCR rate of the PLR-NLR- (PLR- and NLR-) group was 53.7% (22/41), which was significantly higher than that of the PLR+/NLR+ (PLR+ or/and NLR+) group (26.1% [11/42]; P = .012). EFS and OS in the NLR+ group were significantly shorter than those in the NLR- group (P = .028 for EFS; P = .047 for OS). Patients in the PLR-NLR- group had a longer EFS than those in the PLR+/NLR+ group (P = .002).
    CONCLUSIONS: PLR and NLR could be used to predict the efficacy of neoadjuvant therapy with the taxane, anthracycline, and lobaplatin regimen for patients with TNBC, as patients who had lower PLR and NLR values had a higher tpCR rate and a better long-term prognosis.
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  • 文章类型: Journal Article
    现在,通过使用SF5Cl对[1.1.0]双环丁烷(BCB)进行应变释放官能化,可以合成第一批非手性五氟硫烷基化环丁烷(SF5-CB)。本文详述了基于砜的BCB的氯五氟硫烷基化和氢五氟硫烷基化的方法。以及逻辑扩展到四氟(芳基)硫烷基化的概念证明,四氟(三氟甲基)硫基化,和三组分五氟硫酰化反应。提出的方法能够分离SF5-CBs的顺和反异构体,但我们也证明了这种先天的选择性可以在氯五氟硫磺酰化中被推翻;也就是说,可以通过使用廉价的铜盐添加剂来实现跨基于砜的BCB添加SF5Cl的反立体选择性变体。考虑到SF5组和CB已分别用作非经典生物等排体,然后使用SC-XRD对这些独特的SF5-CB“混合等排体”的结构方面进行了上下文分析。从机械的角度来看,氯五氟硫烷基化表面上是通过将亲电SF5自由基奇怪的极性错配添加到BCB的亲电位点来进行的。在检查含羰基的BCB时,我们还观察到罕见的情况,其中自由基添加到BCB的1位发生。通过实验和DFT计算研究了关键C(sp3)-SF5键形成步骤的性质-以及我们公开的方法的其他机械特征。最后,我们证明了SF5-CB与各种下游官能化的兼容性。
    The first assortment of achiral pentafluorosulfanylated cyclobutanes (SF5-CBs) are now synthetically accessible through strain-release functionalization of [1.1.0]bicyclobutanes (BCBs) using SF5Cl. Methods for both chloropentafluorosulfanylation and hydropentafluorosulfanylation of sulfone-based BCBs are detailed herein, as well as proof-of-concept that the logic extends to tetrafluoro(aryl)sulfanylation, tetrafluoro(trifluoromethyl)sulfanylation, and three-component pentafluorosulfanylation reactions. The methods presented enable isolation of both syn and anti isomers of SF5-CBs, but we also demonstrate that this innate selectivity can be overridden in chloropentafluorosulfanylation; that is, an anti-stereoselective variant of SF5Cl addition across sulfone-based BCBs can be achieved by using inexpensive copper salt additives. Considering the SF5 group and CBs have been employed individually as nonclassical bioisosteres, structural aspects of these unique SF5-CB \"hybrid isosteres\" were then contextualized using SC-XRD. From a mechanistic standpoint, chloropentafluorosulfanylation ostensibly proceeds through a curious polarity mismatch addition of electrophilic SF5 radicals to the electrophilic sites of the BCBs. Upon examining carbonyl-containing BCBs, we also observed rare instances whereby radical addition to the 1-position of a BCB occurs. The nature of the key C(sp3)-SF5 bond formation step - among other mechanistic features of the methods we disclose - was investigated experimentally and with DFT calculations. Lastly, we demonstrate compatibility of SF5-CBs with various downstream functionalizations.
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