Thia- and selenaheterocycles by a four-component reaction using elemental sulfur and selenium

The course of the four-component reactions of (2-benzimidazolyl) acetonitrile, carbondisulfide, isothiocyanate, and sulfur and selenium, respectively, is quite different. Whereas in the case of sulfur a tetracyclic [1,3]thiazolo[4 ,5 :4,5]pyrimido[1,6-a]benzimidazol-2(3H)-thione is formed, a zwitterionic 7-(benzimidazolium-2-yl)-[1,2]thiaselenolo[2,3-b][1,2,4]thiaselenazole-6-thiolate (an azaselenadithiapentalene) is the product in the case of selenium. The structures of the products have been established by X-ray crystallography, and reaction mechanisms for their formation are proposed

The hard X-ray Photon Single-Shot Spectrometer of SwissFEL - Initial characterization

SwissFEL requires the monitoring of the photon spectral distribution at a repetition rate of 100 Hz for machine optimization and experiment online diagnostics. The Photon Single Shot Spectrometer has been designed for the photon energy range of 4 keV to 12 keV provided by the Aramis beamline. It is capable of measuring the spectrum in a non-destructive manner, with an energy resolution of Δ E/E = (2-5) × 10-5 over a bandwidth of 0.5% on a shot-to-shot basis. This article gives a detailed description about the technical challenges, structures, and considerations when building such a device, and to further enhance the performance of the spectrometer

In vitro and in vivo evaluation of a somatostatin analogue released from PLGA microspheres

The purpose of this study was to design poly(lactide-co-glycolide) (PLGA) microspheres for the continuous delivery of the somatostatin analogue, vapreotide, over 2–4 weeks. The microspheres were produced by spray-drying and the desired characteristics, i.e. high encapsulation efficiency and controlled release over 2–4 weeks, achieved through optimizing the type of polymer, processing solvent, and co-encapsulated additive. The in vitro release was tested in fetal bovine serum preserved with 0.02% of thiomersal. Furthermore, formulations were injected intramuscularly into rats to obtain pharmacokinetic profiles. Encapsulation efficiency was between 34 and 91%, depending on the particular formulation. The initial peptide release (within 6 h) was lowest, i.e. 1 ng/ml) over 21–28 days in rats was the one made with end-group uncapped PLGA 50:50, the solvent acetic acid and the additive polyethyleneglycol. In conclusion, the optimization of formulation parameters allowed us to produce vapreotide-loaded PLGA microspheres of suitable characteristics for therapeutic use

Frequency, course and correlates of alcohol use from adolescence to young adulthood in a Swiss community survey

BACKGROUND: Few studies have analyzed the frequency of alcohol use across time from adolescence to young adulthood and its outcome in young adulthood. A Swiss longitudinal multilevel assessment project using various measures of psychopathology and psychosocial variables allowed for the study of the frequency and correlates of alcohol use so that this developmental trajectory may be better understood. METHOD: Alcohol use was studied by a questionnaire in a cohort of N = 593 subjects who had been assessed at three times between adolescence and young adulthood within the Zurich Psychology and Psychopathology Study (ZAPPS). Other assessment included questionnaire data measuring emotional and behavioural problems, life events, coping style, self-related cognitions, perceived parenting style and school environment, and size and efficiency of the social network. RESULTS: The increase of alcohol use from early adolescence to young adulthood showed only a few sex-specific differences in terms of the amount of alcohol consumption and the motives to drink. In late adolescence and young adulthood, males had a higher amount of alcohol consumption and were more frequently looking for drunkenness and feeling high. Males also experienced more negative consequences of alcohol use. A subgroup of heavy or problem drinkers showed a large range of emotional and behavioural problems and further indicators of impaired psychosocial functioning both in late adolescence and young adulthood. CONCLUSION: This Swiss community survey documents that alcohol use is problematic in a sizeable proportion of youth and goes hand in hand with a large number of psychosocial problems

Somatic mosaicism and common genetic variation contribute to the risk of very-early-onset inflammatory bowel disease

Abstract: Very-early-onset inflammatory bowel disease (VEO-IBD) is a heterogeneous phenotype associated with a spectrum of rare Mendelian disorders. Here, we perform whole-exome-sequencing and genome-wide genotyping in 145 patients (median age-at-diagnosis of 3.5 years), in whom no Mendelian disorders were clinically suspected. In five patients we detect a primary immunodeficiency or enteropathy, with clinical consequences (XIAP, CYBA, SH2D1A, PCSK1). We also present a case study of a VEO-IBD patient with a mosaic de novo, pathogenic allele in CYBB. The mutation is present in ~70% of phagocytes and sufficient to result in defective bacterial handling but not life-threatening infections. Finally, we show that VEO-IBD patients have, on average, higher IBD polygenic risk scores than population controls (99 patients and 18,780 controls; P < 4 × 10−10), and replicate this finding in an independent cohort of VEO-IBD cases and controls (117 patients and 2,603 controls; P < 5 × 10−10). This discovery indicates that a polygenic component operates in VEO-IBD pathogenesis

Synthesis of a Regular 24-membered Cyclodepsipeptide by Direct Amide Cyclization

The synthesis of a 24-membered cyclic depsipeptide with an alternating sequence of phenyllactic acid and α-aminoisobutyric acid (Aib) is described. The linear precursor was prepared via the ‘azirine/oxazolone method’ using 2,2-dimethyl-3-amino-2H-azirines as building blocks for the α,α-disubstituted α-amino acid Aib. The macrolactonization leading to the cyclodepsipeptide was achieved by the ‘direct amide cyclization’, i. e., by treatment of a solution of the linear precursor in toluene with HCl gas

Synthesis of Bis-Aminoazirines and their Application in Peptide Synthesis

The 'cyclohexane-bridged' bis-(3-amino-2H-azirines) cis- and trans-N,N’-dimethyl-N,N’-diphenyl-1,7-diazadispiro[2.2.2.2]deca-1,7-diene-2,8-diamine (cis-21 and trans-21) were synthesized from the corresponding bis-thioamide 20 by consecutive treatment with COCl2, 1,4-diazabicyclo[2.2.2]octane (DABCO) and NaN3. The reaction of these bis-azirines with different natural α-amino acids gave peptide amides 23. In addition, hydrolysis of the C-terminal amide groups of 23c and subsequent coupling with the Aib synthon 2, i.e., 2,2,N-trimethyl-N-phenyl-2H-azirin-3-amine, showed the applicability of building blocks 21 for peptide synthesis and peptide chain ligation

Synthesis of 1,3-Selenazol-2(3H)-imines

The reaction of N,N’-diarylselenoureas 16 with phenacyl bromide in EtOH under reflux, followed by treatment with NH3 , gave N,3-diaryl-4-phenyl-1,3-selenazol-2(3H)-imines 13 in high yields (Scheme 2). A reaction mechanism via formation of the corresponding Se-(benzoylmethyl)isoselenoureas 18 and subsequent cyclocondensation is proposed (Scheme 3). The N,N’-diarylselenoureas 16 were conveniently prepared by the reaction of aryl isoselenocyanates 15 with 4-substituted anilines. The structures of 13a and 13c were established by X-ray crystallography