Electrophilic alkylation of arenes with 5-bromopyrimidine en route to 4-aryl-5-alkynylpyrimidines

A new synthetic protocol for preparation of medicinally important 4-aryl-5-alkynylpyrimidines is described. The featured approach involves a sequence of chemo- and regioselective Brønsted acid-catalyzed electrophilic alkylation of arenes with 5-bromopyrimidine, followed by oxidative re-aromatization of the formed dihydropyrimidine ring. Finally, palladium-catalyzed Sonogashira cross-coupling reaction provided an end-game strategy.

Efficient assembly of 4-aryl-5-alkynylpyrimidines is described featuring novel Brønsted acid-catalyzed electrophilic alkylation of arenes with 5-bromopyrimidine as a key step.     

Synthesis and photoluminescence properties of hybrid 1D core–shell structured nanocomposites based on ZnO/polydopamine

In the present work, we report on the modelling of processes at the zinc oxide and polydopamine (ZnO/PDA) interface. The PDA layer was deposited onto ZnO nanorods (NRs) via chemical bath deposition. The defect concentrations in ZnO before and after PDA deposition were calculated and analysed. The ZnONRs/PDA core–shell nanostructures were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman and Fourier-transform infrared (FTIR) spectroscopy, photoluminescence (PL) measurements, and diffuse reflectance spectroscopy. The TEM and electron energy loss spectroscopy (EELS) measurements confirmed the conformal coating of PDA, while the PL emission from ZnO and ZnONRs/PDA samples showed a reduction of intensity after the PDA deposition. The decrease of defect concentration participating in PL and quantum efficiency explains the PL reduction. Finally, the observed decrease of activation energies and a shift of the PL peaks are attributed to the formation of an additional local electrical field between the PDA and ZnO nanostructures.

The results shown in this study provide a unique insight into the optical and electronic processes of the ZnO/PDA interface.     

Cross-sectional HIV and HCV cascades of care across the regions of Ukraine between 2019 and 2020: findings from the CARE cohort

Introduction

Eastern Europe is facing major HIV and hepatitis C (HCV) epidemics, with many people living with HIV (PLHIV) and HIV/HCV coinfection living in Ukraine. Despite the previous progress towards care quality improvement, the ongoing war in Ukraine is disrupting HIV and HCV care.

Methods

We described an HIV cascade of care (CoC) in PLHIV from two clinical sites and an HCV CoC for anti-HCV-positive PLHIV from six sites in Ukraine, enrolled in the CARE cohort between 1 January 2019 and 1 June 2020. The cross-sectional HIV CoC and HCV CoC are described at study enrolment.

Results

Of 1028 PLHIV, 1014 (98.6%, 95% confidence interval [CI] 97.7–99.3) were on antiretroviral therapy (ART), and 876 (86.4% of those on ART, 95% CI 84.1–88.4) were virologically suppressed. Of 894 participants on ART >6 months, 90.8% (95% CI 88.7–92.6) were virologically suppressed (HIV-RNA <200 copies/ml). Of 2040 anti-HCV-positive PLHIV, 417 (20.4%, 95% CI 18.7–22.3) were ever tested for HCV-RNA prior to enrolment, ranging from 4.9% to 54.4% across sites, and 13.5% were currently HCV-RNA positive. One hundred and eighteen persons (7.3% of ever chronically infected) had received HCV treatment, and 25 persons (1.6% of ever chronically infected) were cured, with variations across sites (0%–7.5%). The site diagnosing 54.4% of people with chronic HCV was the only one providing free RNA testing for all anti-HCV-positive persons, while the intra-country differences in treatment coverage were driven by the number of available direct-acting antiviral (DAA) courses.

Conclusions

Over 98% of PLHIV in care in both CARE sites in Ukraine were receiving ART, and the target of 90% virally suppressed was achieved in persons >6 months on ART. Only one of six HIV/HCV study sites tested over 50% anti-HCV-positive PLHIV for HCV-RNA and treated over 25% of eligible persons. While free HCV-RNA testing and DAA treatment are paramount to achieving HCV elimination targets, they remained a challenge in Ukraine in 2019–2020. The extent of the HIV and HCV care disruption during the war will be further assessed in the CARE cohort and compared with the pre-war findings.