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The synthesis of BN-containing molecules, which have an interesting isosteric relationship to their parent all-C cores, has drawn a great deal of attention as an avenue to alter and tune molecular function. Nevertheless, many cores with embedded BN are still hard to synthesize, and thus, further effort is required in this direction. Herein, we present an integrated approach to BN-containing polycycles rooted in an exceptionally clean B-N condensation of amines with a tri-allylborane. Having released propene as the only byproduct, the resulting BN precursors are seamlessly telescoped into BN-containing polycyclic cores via a set of additional methodologies, either developed here ad-hoc or applied for the first time for the synthesis of BN-cycles. As the "sharpening stone" of the process, BN-embedded naphthalene, which has previously only been obtained in low yield, can now be synthesized efficiently through propenolysis, ring-closing metathesis and a new high-yielding aromatization. As a more advanced application, an analogously obtained BN-containing bis-enyne is readily converted to BN-containing non-aromatic tetra-, penta- and hexacyclic structures via ring-closing enyne metathesis, followed by the Diels-Alder cycloaddition. The resulting air-sensitive structures are easily handled by preventive hydration (quaternization) of their B-N bridge; reverting this hydration restores the original B sp 2 -N sp 2 structure. In the future, these structures may pave the way to BN-anthracenes and other π-extended BN-arenes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background: Hydatid cysts are most frequently located in the liver and lungs and very rarely can be found in the pericardium. Diagnosis and treatment are quite challenging, as the disease can present itself in many forms depending to the location and the complications that it might cause., Case Presentation: A 22-year-old man presented to our hospital with ongoing dry cough for more than 1 month prior to admission. Other symptoms included chest pain, fatigue, low grade fever, and night sweats, which have worsened in the past 2 weeks. Physical examination revealed normal respiratory and heart function. Chest X-ray demonstrated mediastinal enlargement and left pleural effusion. Contrast-enhanced computed tomography images showed a walled cystic mass lesion measuring up to 56 × 50 mm in close proximity to the upper left atrium, ascending aorta and pulmonary artery, potentially localized in the pericardium, with a 10 mm endoatrial filling defect, findings were compatible with hydatid cyst, left pleural effusion and peripheral pulmonary upper left lobe consolidation. Cardiac involvement was excluded on magnetic resonance imaging and trans-esophageal ultrasound. The patient underwent fine needle aspiration of the affected lung and thoracocentesis. No malignancy was found, meanwhile the biopsy confirmed the presence of pulmonary infarction. In view of the imaging findings were highly suspicious of a hydatid cyst, we performed a test of antibody titers that was negative. The patient underwent left anterolateral thoracotomy, and after the opening of the pericardium, a cystic mass of 5 cm in diameter was found next to the left atrium and in close proximity with the left pulmonary veins. The content of the cyst was completely removed after the surgical area was isolated with gauze impregnated with hypertonic solution (NaCl 10%). The mass resulted to be an echinococcal cyst with multiple daughter cysts within it that did not penetrate/involve (perforate) the cardiac wall., Conclusion: Pericardial echinococcosis is a very rare pathology in which a high expertise multidisciplinary approach is required. The compression mass effect caused by the cyst can lead to complications, such as in our case where the pulmonary vein was compressed, leading to pulmonary infarction. The value of radiology studies and transoesophageal ultrasound are very important in the diagnosis. Surgery in these cases is always recommended, but preferred surgical approach is questionable. In cases such as ours, we recommend anterolateral thoracotomy., (© 2023. The Author(s).)

Lipidation, a common strategy to improve half-life of therapeutic peptides, affects their tendency to oligomerize, their interaction with plasmatic proteins, and their catabolism. In this work, we have leveraged the use of NMR and SPR spectroscopy to elucidate oligomerization propensity and albumin interaction of different analogs of the two marketed lipidated GLP-1 agonists liraglutide and semaglutide. As most lipidated therapeutic peptides are administered by subcutaneous injection, we have also assessed in vitro their catabolism in the SC tissue using the LC-HRMS-based SCiMetPep assay. We observed that oligomerization had a shielding effect against catabolism. At the same time, binding to albumin may provide only limited protection from proteolysis due to the higher unbound peptide fraction present in the subcutaneous compartment with respect to the plasma. Finally, identification of catabolites in rat plasma after SC dosing of semaglutide showed a good correlation with the in vitro data, with Tyr 19 -Leu 20 being the major cleavage site. Early characterization of the complex interplay between oligomerization, albumin binding, and catabolism at the injection site is essential for the synthesis of lipidated peptides with good pharmacokinetic profiles., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)