Selective β-oxidation of α-sulfanyl amides

A selective β-oxidation of a series of α-sulfanyl amides to the corresponding β-oxo-α-sulfanyl amides is described. This selective efficient oxidation of an unfunctionalised methyl or methylene group occurs under mild conditions, involving three sequential transformations conducted without isolation of the intermediates. Critically neither the sulfur nor the reactive α-CH bond is affected in the overall process

Investigating the influence of the sulfur oxidation state on solid state conformation

Design, synthesis and structural characterization of a series of diphenylacetylene derivatives bearing organosulfur, amide and amine moieties has been achieved in which the molecular conformation is controlled through variation of the hydrogen bond properties on alteration of the oxidisation level of sulfur

A study of the norcaradiene-cycloheptatriene equilibrium in a series of azulenones by NMR spectroscopy; the impact of substitution on the position of equilibrium

A systematic investigation of the influence of substitution at positions C-2 and C-3 on the azulenone skeleton, based on NMR characterisation, is discussed with particular focus on the impact of the steric and electronic characteristics of substituents on the position of the norcaradiene-cycloheptatriene (NCD-CHT) equilibrium. Variable temperature (VT) NMR studies, undertaken to enable the resolution of signals for the equilibrating valence tautomers revealed, in addition, interesting shifts in the equilibrium

Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function

Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

One-pot cross-coupling/C–H functionalization reactions: Quinoline as a substrate and ligand through N–Pd interaction

Herein, we report a one-pot process that marries mechanistically distinct, traditional cross-coupling reactions with C–H functionalization using the same precatalyst. The reactions proceed in yields of up to 95%, in air, and require no extraneous ligand. The reactions are thought to be facilitated by harnessing the substrate quinoline as an N-ligand, and evidence of the palladium–quinoline interaction is provided by 1H-15N HMBC NMR spectroscopy and X-ray crystallographic structures. Application of the methodology is demonstrated by the quick formation of fluorescent, π-extended frameworks.<br/

Identification of N- or O-Alkylation of Aromatic Nitrogen Heterocycles and N-Oxides Using H-1-N-15 HMBC NMR Spectroscopy

A series of representative diazines and pyridine N-oxides were subjected to alkylation using several different alkylating agents. The N-15 NMR chemical shifts (delta(N) values) of the diazines, pyridine N-oxides and derived alkylation products were determined using H-1-N-15 HMBC NMR spectroscopy at natural N-15 abundance. The changes in the N-15 NMR chemical shifts (Delta(delta(N)) values) that occurred on going from starting materials to products in these reactions were analyzed. N-alkylation of diazines resulted in large upfield shifts of the delta(N) values of the alkylated nitrogen (of the order of 100 ppm or greater). While O-alkylation of pyridine N-oxides resulted in upfield shifts of the delta(N) values of the N-(alkoxy)pyridinium nitrogen, the Delta(delta(N)) values were of a much smaller magnitude (ca. -42 ppm) than those observed for N-alkylations of diazines. Nitrogen NMR spectroscopic data from the literature of relevance to alkylation of azines, diazines, azine N-oxides and diazine N-oxides was gathered together, and using this in tandem with our N-15 NMR spectroscopic data, we have been able to corroborate our observations on the trends observed in the Delta(delta(N)) values associated with N- and O-alkylation reactions of aromatic N-heterocycles and N-oxides. An analysis protocol that relies on synergistic evaluation of H-1-N-15 HMBC and H-1-C-13 HMBC NMR spectra has been developed that enables unambiguous diagnosis of the occurrence of N-alkylation of aromatic N-heterocycles and O-alkylation of aromatic N-oxides

Competition between N and O: use of diazineN-oxides as a test case for the Marcus theory rationale for ambident reactivity

The preferred site of alkylation of diazineN-oxides by representative hard and soft alkylating agents was established conclusively using the(1)H-N-15 HMBC NMR technique in combination with other NMR spectroscopic methods. Alkylation of pyrazineN-oxides (1and2) occurs preferentially on nitrogen regardless of the alkylating agent employed, whileO-methylation of pyrimidineN-oxide (3) is favoured in its reaction with MeOTf. As these outcomes cannot be explained in the context of the hard/soft acid/base (HSAB) principle, we have instead turned to Marcus theory to rationalise these results. Marcus intrinsic barriers (Delta G double dagger 0) and Delta(r)G degrees values were calculated at the DLPNO-CCSD(T)/def2-TZVPPD/SMD//M06-2X-D3/6-311+G(d,p)/SMD level of theory for methylation reactions of1and3by MeI and MeOTf, and used to derive Gibbs energies of activation (Delta G(double dagger)) for the processes ofN- andO-methylation, respectively. These values, as well as those derived directly from the DFT calculations, closely reproduce the observed experimentalN- vs.O-alkylation selectivities for methylation reactions of1and3, indicating that Marcus theory can be used in a semi-quantitative manner to understand how the activation barriers for these reactions are constructed. It was found thatN-alkylation of1is favoured due to the dominant contribution of Delta(r)G degrees to the activation barrier in this case, whileO-alkylation of3is favoured due to the dominant contribution of the intrinsic barrier (Delta G double dagger 0) for this process. These results are of profound significance in understanding the outcomes of reactions of ambident reactants in general

Mechanistic study of in situ generation and use of methanesulfonyl azide as a diazo transfer reagent with real-time monitoring by FlowNMR

The mechanistic pathway by which the hazardous diazo transfer reagent methanesulfonyl azide can be formed in situ, from methanesulfonyl chloride and aqueous sodium azide, has been investigated using real-time reaction monitoring by FlowNMR. In the presence of triethylamine, rapid generation of methanesufonyl azide is observed, via a mechanistic pathway consistent with involvement of a sulfene or methanesulfonyl triethylammonium intermediate. Accordingly, it is possible to generate and use methanesulfonyl azide in a single synthetic step for a diazo transfer process