11 research outputs found

    Concise Synthesis of (+)-allo-Kainic Acid via MgI2-Mediated Tandem Aziridine Ring Opening-Formal [3+2] Cycloaddition

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    3-Methyl vinyl aziridine undergoes a mild MgI2-promoted S(N)2' ring opening and concomitant cyclization with fumarate Michael acceptors to give trisubstituted pyrrolidines. The process is efficient and highly diastereoselective. This methodology has been applied to a concise asymmetric synthesis of (+)-allo-kainic acid.</p

    DNA methylation patterns identify subgroups of pancreatic neuroendocrine tumors with clinical association

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    Here we report the DNA methylation profile of 84 sporadic pancreatic neuroendocrine tumors (PanNETs) with associated clinical and genomic information. We identified three subgroups of PanNETs, termed T1, T2 and T3, with distinct patterns of methylation. The T1 subgroup was enriched for functional tumors and ATRX, DAXX and MEN1 wild-type genotypes. The T2 subgroup contained tumors with mutations in ATRX, DAXX and MEN1 and recurrent patterns of chromosomal losses in half of the genome with no association between regions with recurrent loss and methylation levels. T2 tumors were larger and had lower methylation in the MGMT gene body, which showed positive correlation with gene expression. The T3 subgroup harboured mutations in MEN1 with recurrent loss of chromosome 11, was enriched for grade G1 tumors and showed histological parameters associated with better prognosis. Our results suggest a role for methylation in both driving tumorigenesis and potentially stratifying prognosis in PanNETs

    A highly stereo-controlled protocol to prepare pipecolic acids based on Heck and cyclohydrocarbonylation reactions

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    A novel synthetic protocol based on an indium-mediated glyoxylate allylation, Heck coupling and Rh-catalysed cyclohydrocarbonylation (CHC) was established to access enantiomerically pure polysubstituted pipecolic acids. The key steps are the Heck reaction, which is performed exclusively using a phenone-oxime derived palladacycle and the domino hydroformylation-cyclisation of a styryl derivative obtained from the Heck coupling. The reaction scheme, proceeding with good stereoselectivity, is also suitable for the preparation of substituted piperidine derivatives

    A highly stereo-controlled protocol to prepare pipecolic acids based on Heck and cyclohydrocarbonylation reactions

    No full text
    A novel synthetic protocol based on an indium-mediated glyoxylate allylation, Heck coupling and Rh-catalysed cyclohydrocarbonylation (CHC) was established to access enantiomerically pure polysubstituted pipecolic acids. The key steps are the Heck reaction, which is performed exclusively using a phenone-oxime derived palladacycle and the domino hydroformylation-cyclisation of a styryl derivative obtained from the Heck coupling. The reaction scheme, proceeding with good stereoselectivity, is also suitable for the preparation of substituted piperidine derivative

    Concise Synthesis of (+)-<i>allo</i>-Kainic Acid <i>via</i> MgI<sub>2</sub>‑Mediated Tandem Aziridine Ring Opening–Formal [3 + 2] Cycloaddition

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    3-Methyl vinyl aziridine undergoes a mild MgI<sub>2</sub>-promoted S<sub>N</sub>2′ ring opening and concomitant cyclization with fumarate Michael acceptors to give trisubstituted pyrrolidines. The process is efficient and highly diastereoselective. This methodology has been applied to a concise asymmetric synthesis of (+)-<i>allo</i>-kainic acid

    Synthesis of Lipophilic Core-Shell Fe3O4@SiO2@Au Nanoparticles and Polymeric Entrapment into Nanomicelles: A Novel Nanosystem for in Vivo Active Targeting and Magnetic Resonance-Photoacoustic Dual Imaging

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    In this work, iron/silica/gold core-shell nanoparticles (Fe3O4@SiO2@Au NPs) characterized by magnetic and optical properties have been synthesized to obtain a promising theranostic platform. To improve their biocompatibility, the obtained multilayer nanoparticles have been entrapped in polymeric micelles, decorated with folic acid moieties, and tested in vivo for photoacoustic and magnetic resonance imaging detection of ovarian cancer

    Novel Gastrin-Releasing Peptide Receptor Targeted Near-Infrared Fluorescence Dye for Image-Guided Surgery of Prostate Cancer

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    Purpose Prostate cancer (PCa), the most widespread male cancer in western countries, is generally eradicated by surgery, especially if localized. However, during surgical procedures, it is not always possible to identify malignant tissues by visual inspection. Among the possible consequences, there is the formation of positive surgical margins, often associated with recurrence. In this work, the gastrin-releasing peptide receptor (GRPR), overexpressed in the prostatic carcinoma and not in healthy tissues or in benign hyperplasia (BPH), is proposed as target molecule to design a novel near-infrared fluorescent (NIRF) probe for image-guided prostatectomy. Procedures The NIRF dye Sulfo-Cy5.5 was conjugated to a Bombesin-like peptide (BBN), targeting GRPR. The final product, called BBN-Cy5.5, was characterized and tested in vitro on PC-3, DU145, and LnCAP cell lines, using unconjugated Sulfo-Cy5.5 as control. In vivo biodistribution studies were performed by optical imaging in PC-3 tumor-bearing and healthy mice. Finally, simulation of the surgical protocol was carried out. Results BBN-Cy5.5 showed high water solubility and a good relative quantum yield. The ability of the probe to recognize the GRPR, highly expressed in PC-3 cells, was tested both in vitro and in vivo, where a significant tumor accumulation was achieved 24 h post-injection. Furthermore, a distinguishable fluorescent signal was visible in mice bearing PCa, when the surgery was simulated. By contrast, low signal was found in healthy or BPH-affected mice. Conclusions This work proposes a new NIRF probe ideal to target GRPR, biomarker of PCa. The promising data obtained suggest that the dye could allow the real-time intraoperative visualization of prostate cancer

    Synthesis of Lipophilic Core–Shell Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>@Au Nanoparticles and Polymeric Entrapment into Nanomicelles: A Novel Nanosystem for in Vivo Active Targeting and Magnetic Resonance–Photoacoustic Dual Imaging

    No full text
    In this work, iron/silica/gold core–shell nanoparticles (Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>@Au NPs) characterized by magnetic and optical properties have been synthesized to obtain a promising theranostic platform. To improve their biocompatibility, the obtained multilayer nanoparticles have been entrapped in polymeric micelles, decorated with folic acid moieties, and tested in vivo for photoacoustic and magnetic resonance imaging detection of ovarian cancer
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