In the presence of a diarylborinic acid catalyst, glycosyl methanesulfonates engage in regio- and stereoselective couplings with partially protected pyranoside and furanoside acceptors. The ...methanesulfonate donors are prepared in situ from glycosyl hemiacetals, and are coupled under mild, operationally simple conditions (amine base, organoboron catalyst, room temperature). The borinic acid catalyst not only influences site-selectivity via activation of 1,2- or 1,3-diol motifs, but also has a pronounced effect on the stereochemical outcome: 1,2-trans-linked disaccharides are obtained selectively in the absence of neighboring group participation. Reaction progress kinetic analysis was used to obtain insight into the mechanism of glycosylation, both in the presence of catalyst and in its absence, while rates of interconversion of methanesulfonate anomers were determined by NMR exchange spectroscopy (EXSY). Together, the results suggest that although the uncatalyzed and catalyzed reactions give rise to opposite stereochemical outcomes, both proceed by associative mechanisms.
The direct α-sulfidation of tertiary amides using sulfoxide reagents under electrophilic amide activation conditions is described. Employing convenient and readily available reagents, selective ...functionalization takes place to generate isolable sulfonium ions en route to α-sulfide amides. Mechanistic studies identified activated sulfoxides as promoters of the desired transformation and enabled the extension of the methodology from benzylic to aliphatic amide substrates.
Total synthesis of himastatin D'Angelo, Kyan A; Schissel, Carly K; Pentelute, Bradley L ...
Science,
02/2022, Volume:
375, Issue:
6583
Journal Article
Peer reviewed
Open access
The natural product himastatin has an unusual homodimeric structure that presents a substantial synthetic challenge. We report the concise total synthesis of himastatin from readily accessible ...precursors, incorporating a final-stage dimerization strategy that was inspired by a detailed consideration of the compound's biogenesis. Combining this approach with a modular synthesis enabled expedient access to more than a dozen designed derivatives of himastatin, including synthetic probes that provide insight into its antibiotic activity.
Epithiodiketopiperazines (ETPs) are a structurally complex class of fungal natural products with potent anticancer activity. In ETPs, the diketopiperazine ring is spanned by a disulfide bond that is ...constrained in a high-energy eclipsed conformation. We employed computational, synthetic, and spectroscopic methods to investigate the physicochemical attributes of this atypical disulfide bond. We find that the disulfide bond is stabilized by two n→π* interactions, each with large energies (3–5 kcal/mol). The n→π* interactions in ETPs make disulfide reduction much more difficult, endowing stability in physiological environments in a manner that could impact their biological activity. These data reveal a previously unappreciated means to stabilize a disulfide bond and highlight the utility of the n→π* interaction in molecular design.
This study aimed to explore the socio-economic inequalities in physical activity (PA) based on domains of daily life, such as work, transport, recreation and sedentary life, among Japanese adults ...during the COVID-19 pandemic.
This was a cross-sectional study.
This study used data from the 2020 National Sport and Lifestyle Survey, conducted by the Sasakawa Sports Foundation. Data of 2,296 (1,103 women) participants were analysed. PAs were assessed using the Global Physical Activity Questionnaire. Educational level and household income were used as indicators of socio-economic status. We calculated the slope index of inequality (SII) and relative index of inequality (RII).
We detected absolute and relative inequalities for household income in all PA domains, except for work-related PA. The higher the participants’ income, the longer they engaged in transport- and recreation-related PA and sedentary behaviour. Recreation-related PA had a larger disparity than other domains, with SII at 20.8% (95% confidence interval CI −28.4 to −13.1) and RII at 0.58 (95% CI 0.47–0.71). At the educational level, each inequality was observed in work- and recreation-related PA and sedentary behaviour. The higher the participants’ educational level, the longer they engaged in recreation-related PA and sedentary behaviour. However, work-related PA was longer at lower educational levels, with RII at 1.90 (95% CI 1.48–2.44). The inequality in recreation-related PA was also relatively large (SII 23.3%, 95% CI −30.9 to −15.7; RII 0.54, 95% CI 0.45–0.66).
Our study revealed significant socio-economic disparities in each PA domain, particularly in recreational PA. These results suggest a widening gap because of the COVID-19 pandemic.
The catalytic, undirected borylation of alkyl C–H bonds typically occurs at high reaction temperatures or with excess substrate, or both, because of the low reactivity of alkyl C–H bonds. Here we ...report a new iridium system comprising 2-anilino-1,10-phenanthroline as the ligand that catalyzes the borylation of alkyl C–H bonds with little to no induction period and with high reaction rates. This superior activation and reactivity profile of 2-aminophenanthroline-ligated catalysts leads to broader reaction scope, including reactions of sensitive substrates, such as epoxides and glycosidic acetals, enhanced diastereoselectivity, and higher yields of borylated products. These catalysts also enable the borylation of alkanes, amines, and ethers at room temperature for the first time. Mechanistic studies imply that facile N-borylation occurs under the reaction conditions and that iridium complexes containing N-boryl aminophenanthrolines are competent precatalysts for the reaction.
This study aimed to determine the associations between adherence to 24-h movement behavior guidelines and self-rated health (SRH) among Japanese adolescents according to their age group.
This was a ...cross-sectional study.
Probability proportional sampling data, which were collected from six regions of Okinawa Prefecture, Japan, considering the number of schools, included 2408 fifth-grade students (aged 10–11 years) in 31 elementary schools and 4360 eighth-grade students (aged 13–14 years) in 30 junior high schools. SRH, moderate-to-vigorous physical activity (MVPA), screen time (ST), sleep duration, and confounding factors (sex, weight status, family affluence, parental support, school satisfaction, and school demands) were self-reported.
The logistic regression models showed that adherence to ST and sleep recommendations in elementary school students was associated with a high prevalence of good health only, whereas adherence to only MVPA, only sleep, ST and sleep, MVPA and sleep, and all three recommendations were associated with a high prevalence of good health among junior high school students. All combinations that included achievement of the recommended sleep duration were associated with SRH.
Achieving 24-h movement behavior guidelines, particularly sleep recommendations, is associated with better perceived health in school-aged children, especially in adolescents.
Purpose
We have less understanding of which socioeconomic status (SES) indicators may be reflective of latent socioeconomic inequalities in toothbrushing behaviours, especially ...finishing-toothbrushing by parents in young children. The aim of this study was to reveal the socioeconomic inequalities in children’s toothbrushing and finishing-toothbrushing by parents and if it varies by SES indicators.
Methods
We used data from ‘Survey on Children’s Life’ conducted by A city of Okinawa Prefecture, Japan. The multiple imputed data of 902 (boys, 453) included self-reported children’s toothbrushing behaviour and finishing-toothbrushing by parents in three-to six-year-old children. SES was assessed using self-reported household income and parental educational attainment. Absolute and relative inequalities in toothbrushing behaviours were quantified using the slope index of inequality (SII) and relative index of inequality (RII), respectively.
Results
There were significant absolute and relative inequalities of children’s toothbrushing for household income (SII and RII were 0.241 and 2.73, respectively), of finishing-toothbrushing by parents for household income (SII and RII were 0.133 and 3.28, respectively), and educational attainment (SII and RII were 0.166 and 5.55, respectively). The same inequality trends were observed after adjusting for covariates (child’s age and sex, family structure, breakfast and dinner frequency, and sleep duration).
Conclusion
Socioeconomic inequalities in children’s toothbrushing and finishing-toothbrushing by parents varied according to SES indicators.
Abstract
Background
There are numerous reports that social and emotional skills in early childhood have profound influence on lifelong health. The aim of this research is to determine the relation ...between the lifestyle and the social and emotional skills among children in present day Japan.
Methods
The object of analysis was a total of 110 parents of kindergarten students (56 boys, 48 girls,6 gender unknown) from 3 kindergartens in central Okinawa Island. The survey was conducted in mid-December 2019. Regarding the content of the survey, parents were asked to answer on a five-point scale, based on their subjective opinion, how good is their child, as compared to other children, in each of the 9 sub-scales of the social and emotional skills proposed in the 2015 OECD report, namely “perseverance,” “self-control,” “passion for goals,” “sociability,” “respect,” “caring,” “self-esteem,” “optimism,” “confidence.” Additionally, other question items were set, mainly to ask about the child's own lifestyle.
Results
The results of multivariate logistic regression analysis are following. As for “achieving goals:” 3 items for perseverance - “there are few likes and dislikes about food (OR:2.67, 95％CI:1.03～6.94, p=.043),” “Time for playing games on smartphone is determined (OR:3.21, 95％CI:1.19～8.68, p=.021),” “Eat more fruits (OR:3.03, 95％CI:1.24～8.26, p=.016),” are statistically significant. Other results are omitted in this abstract
Conclusions
It became clear that the acquisition of social and emotional skills during early childhood generally involves regular lifestyle and “discipline” at home as a whole. Besides, it is important for parent and child to do various activities together, including those aiming to increase cognitive skills. This study is considered to be a powerful evidence for the development of future intervention programme, aimed at acquiring social and emotional skills in early childhood.
Key messages
In early childhood family and kindergarten have to cooperate to foster social and emotional skills, important for lifelong health. This study is considered to be a powerful evidence for the development of future intervention programme, aimed at acquiring social and emotional skills in early childhood.
We prospectively examined influence of androgen deprivation therapy (ADT) on lipid and glucose metabolisms in Japanese patients with prostate cancer.
Patients with prostate cancer who were ...hormone-naive and scheduled to receive long-term ADT were recruited between 2011 and 2013. Body weight, abdominal circumference and blood testing associated with lipid and glucose metabolism were recorded every 3 months during 1 year of ADT. Computed tomography (CT) was performed to measure areas of subcutaneous and visceral fat before and after 1 year of ADT. ADT was limited to a luteinizing hormone-releasing hormone (LHRH) agonist with or without bicalutamide.
Of 218 patients registered, data were available from 177 patients who completed 1 year of ADT. Of these, CT was performed before and after 1 year of ADT in 88 patients. Median age was 75 years (range, 49-85 years). Median PSA before ADT was 16.7 ng ml(-1) (range, 0.3-3316). Clinical stage was B (54.2%), C (23.2%) and D (20.9%). Mean increases in body weight and abdominal circumference after 1 year of ADT were 2.9 and 3.0%, respectively. Mean increases in total, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides were 10.6, 14.3, 7.8 and 16.2%, respectively. Mean increases in fasting blood sugar and hemoglobin A1c (HbA1c) were 3.9 and 2.7%, respectively. Lipid alterations were noted in patients without comorbidities, whereas changes in HbA1c were noted in patients with diabetes mellitus at baseline. These lipid and glucose alterations were prominent in the early ADT period. Both visceral and subcutaneous fat, as measured by CT, increased by >20%. The increase in subcutaneous fat was significantly greater than that in visceral fat (P=0.028).
One year of ADT significantly changed lipid and glucose metabolism in Japanese patients with prostate cancer. Patient characteristics or comorbidities at baseline may be associated with ADT-induced metabolic changes.
PDF
