Conditions for the Palladium-Catalysed Direct 2-Arylation of 3-Bromobenzo[b]thiophene Tolerant of the Benzothienyl Carbon-Bromine Bond

International audiencePhosphine-free palladium(II) acetate catalyst was found to promote the direct 2-arylation of 3-bromobenzo[b]thiophene without cleavage of the benzothienyl carbon-bromine bond, allowing the synthesis of 2-aryl-3-bromobenzo[b]thiophenes in only one step. The best results were generally obtained using a low loading of the palladium catalyst (0.5 mol%), quite low reaction temps. (80-120 °C) and short reaction times (0.5-2 h). The reaction proceeds with electron-deficient para-, meta- and ortho-substituted aryl bromides and also with heteroaryl bromides. The benzothienyl carbon-bromine bond has been profitably employed for further palladium-catalyzed functionalisations. This strategy allows the straightforward synthesis of 2,3-di(hetero)arylated benzo[b]thiophenes with two different (hetero)aryl units via sequential catalytic arylations

Nasal oral fistula revealing Langerhans´ cell histiocytosis in adult patient: case report

Langerhans cell histiocytosis (LCH) is a rare systemic disease caused by proliferation of mature histiocytes; its association to histiocyto fibroma is rarely reported. It rarely affects adults. We report a case of systemic LCH, in an adult patient with osteolytic lesion causing a fistula between the left nasal cavity and hard palate, involving the bone, lung, lymph node and associated to multiple histiocyto fibroma. The patient was operating for a fistula, and he was treated by chemotherapy and corticosteroids. Langerhans´ cell histiocytosis is a rare case, especially in adult patient. The diagnosis was based on histological and immunohistochemical analyses. This patient was treated by steroids and chemotherapy

Comparison of time to negative conversion of SARS-CoV-2 between young and elderly among asymptomatic and mild COVID-19 patients: a cohort study from a national containment center

ObjectiveWe aimed to study the relationship between age and time to negative conversion of SARS-CoV-2 in patients with asymptomatic and mild forms of COVID-19.MethodsWe conducted a cohort study including all patients diagnosed with COVID-19 from the national COVID-19 containment center of Tunisia. Patients were subdivided into two cohorts: (under 60 years) and (over 60 years) and were followed up until PCR negativization. Log rank test and Cox regression were applied to compare time to negative conversion between the old group and the young group.ResultsThe study included 289 patients with non-severe forms of COVID-19. Age over 60 was significantly associated with delayed negative conversion in male sex (Hazard ratio (HR): 1.9; 95% CI: 1.2–3.07) and among patients with morbid conditions (HR:1.68; 95% CI: 1.02–2.75) especially diabetics (HR: 2.06; 95% CI: 1.01–4.21). This association increased to (HR:2.3; 95% CI: 1.13–4.66) when male sex and comorbidities were concomitantly present and rose to (HR: 2.63; 95% CI: 1.02–6.80) for men with diabetes. Cox regression analysis revealed a significantly delayed negative conversion in symptomatic patients. Significant interaction was observed between gender and age and between age and chronic conditions.ConclusionAge is associated with delayed negative conversion of viral RNA in certain subgroups. Identifying these subgroups is crucial to know how prioritize preventive strategies in elderly

Bacteriological and physico-chemical assessment of wastewater in different region of Tunisia: impact on human health

<p>Abstract</p> <p>Background</p> <p>In many parts of the world, health problems and diseases have often been caused by discharging untreated or inadequately treated wastewater. In this study, we aimed to control physico-chemical parameters in wastewater samples. Also, microbiological analyses were done to reveal <it>Salmonella </it>strains and each <it>Escherichia coli </it>(<it>E.coli</it>) pathotype.</p> <p>Findings</p> <p>Sixty wastewater samples were collected from fifteen different regions of Tunisia. All physico-chemical parameters (pH, residual free chlorine, total suspended solids, biological oxygen demand, and chemical oxygen demand) were evaluated.</p> <p>For microbiological analyses, samples were filtered to concentrate bacteria. DNA was extracted by boiling and subjected to polymerase chain reaction (PCR) using different pairs of primers.</p> <p>The mean pH values recorded for the sampling point were above the WHO pH tolerance limit. The total suspended solids (TSS) concentrations varied between 240 mg/L and 733 mg/L in entrance points and between 13 mg/L and 76 mg/L in exit points. In entrance points, the studied wastewater has an average COD concentration that varied between 795 mg/mL to 1420 mg/mL. Whereas, BOD concentration of the wastewater ranged between 270 mg/L to 610 mg/L. In exit points, COD concentration varied between 59 mg/L and 141 mg/L, whereas BOD concentration ranged from 15 mg/L to 87 mg/L.</p> <p>The bacteriological control of wastewaters showed that, in entrance points, <it>Escherichia coli </it>(<it>E.coli</it>) was detected at the rate of 76.6%. Three <it>E.coli </it>pathotypes were found: ETEC (53.3%), EAEC (16.6%) and EIEC (6.6%).</p> <p>Concerning the ETEC isolated strains, 8 of 16 (50%) have only the heat-labile toxin gene, 5 of 16 (31.2%) present only the heat-stable toxin gene and 3 of 16 (18.7%) of strains possess both heat-labile toxin gene and heat-stable toxin gene. In exist point, the same pathotypes were found but all detected ETEC strains present only the "est" gene.</p> <p>Concerning <it>Salmonella </it>isolated strains; percentages of 66.6% and 20% were found in entrance and exit points respectively.</p> <p>Conclusions</p> <p>Wastewaters contain a large amount of pathogenic bacteria that present a real impact on human health. Assessment wastewater treatment stations have to consider in account enterobacterial pathogens as potential pathogens that should be correctly controlled.</p

Reactivity of 3-(pyrrol-1-yl)thiophenes in Pd-catalysed direct arylations

International audienceThe regioselectivity of the Pd-catalysed direct arylation of 3-(pyrrol-1-yl)thiophene derivatives was investigated. Conditions allowing either the regioselective arylation at C2 or at C5 of the thiophene ring are reported. From methyl 3-(pyrrol-1-yl)thiophene-2-carboxylate using KOAc as the base, DMA as the solvent and only 1 mol % Pd(OAc)2 catalyst, the target 5-arylated thiophenes were obtained in moderate to good yields with a wide variety of aryl halides; whereas the use of 1-(4-methylthiophen-3-yl)-pyrrole affords the C2-arylated thiophenes. The sequential palladium catalysed 2,5-diheteroarylation of such 3-(pyrrol-1-yl)thiophene is also reported allowing the access to thiophenes bearing two different aryl units at C2 and C5. A pyrazole bearing an ester substituent at C4 and a pyrrole substituent at C5 was only arylated at C2 on the pyrrole ring

Conditions for palladium-catalyzed direct arylations of 4-bromo and 4-iodo N-substituted pyrazoles without C-Br or C-I bond cleavage

International audienceThe Pd-catalyzed arylation at the C5 position of N-protected pyrazole derivs. bearing bromo or iodo substituents at the C4 position is described. A simple phosphine-free catalytic system was used, namely, 1 mol% Pd(OAc)2 in DMA in the presence of KOAc as the base. A wide aryl bromide scope as a coupling partner has been coupled with pyrazole derivs. The reaction was very chemoselective as the C-halogen bonds of the pyrazole units were not involved in the C-H bond arylation process. Some examples demonstrating the synthetic potential of the bromo and iodo pyrazole substituents for chem. transformations are reported

Systemic lupus erythematosus, antiphospholipid syndrome and Hashimoto thyroiditis occurring in a patient with Niemann-Pick disease: a second case

Lysosomial diseases and autoimmune diseases are systemic disorders. Their clinical manifestations can overlap with the broad spectrum of one another. Their association has been rarely reported. We report a new case of systemic lupus erythematous (SLE) associated to antiphospholipid syndrome (APS) and Hashimoto thyroiditis occurring in Niemann-Pick disease (NPD) type B patient. A 42-year-old woman with a familial history of NPD was diagnosed with a NPD type B at the age of ten. Twenty years later (2008), she complained of inflammatory arthralgia with acute dyspnea. She was diagnosed with SLE (according to ACR criteria) and Hashimoto disease with positive IgG anti-cardiolipin and IgA anti-beta2 glycoprotein. In 2018, she presented a left segmental pulmonary embolism. Antiphospholipid syndrome was retained. She was treated with steroids, hydroxychloroquine, anticoagulation therapy and levothyroxine. Her SLE treatment was re-enforced by cyclophosphamide because of corticosteroid dependence and recurrent hemolytic crises

Complement receptor 1 gene polymorphisms in Tunisian

patients with systemic lupus erythematosu