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Formation of valuable spiroheterocycles with multiple contiguous stereogenic centres from palladium-catalysed enantioselective (3 + 2) cycloaddition reactions of sulfamidate-derived azadienes and vinylcyclopropanes.

Mutations in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome continue to threaten the global landscape of the coronavirus disease 2019 (COVID-19) pandemic. The Omicron variant (B.1.1.529) rapidly displaced previous ‘variants of concern’ (VoC) in 2021 due to its high rate of transmissibility and multitude of mutations. This global influx of infections saturated healthcare systems, overwhelmed testing capacity and case reporting, and increased the COVID-19 death toll. Global health leaders are now being faced with the most transmissible COVID-19 variants yet, the Omicron sublineages BA.4 and BA.5, which contain additional spike protein (S) mutations from previous Omicron and VoC serotypes. With universally observed antibody waning, increasing vaccine-variant mismatch, and resuming international travel, the stage is set for unprecedented levels of breakthrough infections and superspreading events. In this paper, we raise awareness to these novel variants and provide context for the high likelihood of an upcoming wave of infection capable of inflicting significant disease burden on a global scale.

Background Underserved and minority populations are often reluctant to engage in advance care planning and/or research often due to distrust in healthcare and/or research institutions. Aim To determine if use of a community-based delivery model can facilitate recruitment of individuals from underserved communities in research about advance care planning. Design Recruitment data are presented from a prospective, mixed methods observational cohort study that examined the feasibility and preliminary efficacy of a community-based delivery model involving an end-of-life conversation game to motivate participants to complete advance care planning behaviors. Event attendance and research participation data are reported. Setting/participants Game events were held in community venues in 27 states across the US in 2018-2019. The model involved leveraging existing social networks to recruit attendees and research participants to community game day events. Attendees were eligible for research if they were adults who read/spoke English. Results 1,122 individuals attended events at 53 sites. Participants generally reported low income (48% reported $30,000 annual income). At sites with research assistants, there was a 90% consent rate (92% were Black). At community outreach sites, 45% agreed to a follow-up research phone call (49% were Black). Conclusions Use of the community-based delivery model successfully engaged undeserved communities in a research-based advance care planning related community outreach event. This model may be useful for overcoming underserved and minority populations’ skepticism and distrust of healthcare and research that is a common barrier to progress in health agendas, especially advance care planning.

Herein, we report coupling in situ high temperature postsynthetic modifications (PSMs) in metal–organic frameworks (MOFs). Thermo-reactive propargyloxy-functionalized zinc IRMOFs (isoreticular metal–organic frameworks) prepared from 2-(prop-2-yn-1-yloxy)-[1,1′-biphenyl]-4,4′-dicarboxylic acid (H2bpdcOCH2CCH) were investigated for their high-temperature postsynthetic rearrangement (PSR) chemistry to heterocyclic chromenes and benzofurans and then coupled to solid–gas reactions with molecular oxygen. The selectivity for the initial molecular rearrangements was found to be inverted in the porous MOF environment compared to conventional melt reactions of the ester compound Me2bpdcOCH2CCH and proceeded far more easily than the solid-state transformation from H2bpdcOCH2CCH, showing the potential of MOFs to give rise to different chemistry. The major oxidative process was thermolysis of the chromene ring with a minor pathway of allylic-type oxidation to give heterocyclic chromenone functionality. The sequence was also successful on a series of two-component multivariate IRMOF frameworks prepared from thermo-reactive H2bpdcOCH2CCH and thermo-resistant H2bpdcOMe linkers, demonstrating that these reactions can be used with known crystal engineering strategies. All transformations were fully compatible with the requirements to maintain MOF crystallinity and porosity as evidenced by surface area analysis and X-ray powder diffraction measurements. This work contributes to establishing the feasibility of high-temperature solid–gas manifolds for MOF PSM.

A highly diastereoselective method for the synthesis of syn-β-amino alcohols and enantioenriched anti-β-amino alcohols has been developed involving α-hydroxyl aldehydes and chiral α-phenylaminoxyaldehydes or α-benzoyloxyaldehydes, respectively in Petasis borono-Mannich allylation reactions.

Over the past decade, CRISPR/Cas-based gene editing has become a powerful tool for generating mutations in a variety of model organisms, from Escherichia coli to zebrafish, rodents and large mammals. CRISPR/Cas-based gene editing effectively generates insertions or deletions (indels), which allow for rapid gene disruption. However, a large proportion of human genetic diseases are caused by single-base-pair substitutions, which result in more subtle alterations to protein function, and which require more complex and precise editing to recreate in model systems. Precise genome editing (PGE) methods, however, typically have efficiencies of less than a tenth of those that generate less-specific indels, and so there has been a great deal of effort to improve PGE efficiency. Such optimisations include optimal guide RNA and mutation-bearing donor DNA template design, modulation of DNA repair pathways that underpin how edits result from Cas-induced cuts, and the development of Cas9 fusion proteins that introduce edits via alternative mechanisms. In this Review, we provide an overview of the recent progress in optimising PGE methods and their potential for generating models of human genetic disease.

PurposeWithin the expatriation subset of the wider IB literature, the focus of research has been on contemporary contextual factors. The purpose of this paper is to link the present to the past by investigating how the individual expatriate experience may be affected by a colonial legacy between host and home countries.Design/methodology/approachGiven the exploratory nature of this study, a qualitative interview-based approach eliciting thick, detailed descriptions of the practical experiences of seven Japanese expatriate managers working in Malaysia was adopted. These were supplemented by additional interviews with three host-country nationals who work alongside some of the expatriates. The data were analysed through a two-stage coding process.FindingsThe expatriate respondents were largely unanimous in their view that the colonial past between the two countries had no negative impact on their experiences in Malaysia, and the Malaysian interviewees corroborated this. On the contrary, the majority of the expatriates actually spoke positively about their experiences. This was especially true for expatriates in both the tourism and education/research field whose work was linked in some way to the period of Japanese occupation.Research limitations/implicationsThe small, single-context nature of the investigation limits generalisation. There are also many particularities in this study (the nature of Japanese-Malaysian postcolonial relations, cultural values of the Malaysians and Japanese, and so on) that are perhaps not easily relatable to other contexts. Having said this, qualitative research is not always geared towards generalisability but rather towards contextual intricacies and nuances.Originality/valueWhile most of the extant literature on expatriation has examined largely contemporary factors, this paper explores the impact of more historical events on the expatriate experience. Although such events may seem distant from an expatriate's current activities, this study suggests that in certain circumstances, they may have a lingering effect.

PurposeThe purpose of this study is to investigate the relationship between ethical leadership and the quality of the manager-subordinate relationship, as well as the moderating effect of female employees’ psychological empowerment on this relationship.Design/methodology/approachThis is quantitative research in which an online questionnaire was distributed to female subordinates from multinational enterprises in Malaysia (n= 120). A partial least square is used for analysis in this research.FindingsThe findings confirm a strong positive correlation between all the seven ethical leadership dimensions and the quality of manager-subordinate relationship (leader member exchange). However, the moderating effect of psychological empowerment was found to be insignificant for two of the seven dimensions of ethical leadership.Originality/valueThis study contributes to highlighting new perspectives of women empowerment. Moreover, it also uncovers psychological factor that influences manager-subordinate relationship using cognitive evaluation theory. The seven dimensions of ethical leadership have not been tested in the past studies (only identified, not tested separately).

The Pd-catalysed asymmetric allylic alkylation (Pd-AAA) of prochiral enamide anions derived from 5H-oxathiazole 2,2-dioxides has been developed. Various 4,5-disubstituted and 4-substituted cyclic sulfamidate imines have participated in the transformation with a range of allyl carbonates—as well as 2-vinyl oxirane, 2-vinyl-N-tosylaziridine, and 2-vinyl-1,1-cyclopropane dicarboxylate—to furnish the desired C-allylated products in moderate to high yields, with high regioselectivites and generally high enantioselectivities. Conversion between N- and C-allyl products was observed, with the N-allylated products converting to the C-allylated products over time. The resulting high-value allylated heterocyclic products all bear a tetrasubstituted stereogenic centre and can be reduced to an allylated chiral sulfamidate or an amino alcohol., The Pd-catalysed asymmetric allylic alkylation (Pd-AAA) of prochiral enamide anions derived from 5H-oxathiazole 2,2-dioxides has been developed.

Tailoring the pore environments of metal-organic frameworks (MOFs) is key to improving their performance and expanding their applicability. Postsynthetic methods, wherein an already synthesized MOF undergoes further chemical reactions, present many advantages for such tailoring and lead to much interesting new chemistry. However, this method has seldom been pushed farther than two reaction steps on the organic component. Here we report a three-step sequence starting from an alkenyl group on the biphenyl backbone of an IRMOF-9 analogue. The alkene is converted to an oxirane group and subsequently to a 1,2-azidoalcohol. The ultimate product is a framework functionalized with an aziridine ring. The reaction efficiency of each step is high, which suppresses the formation of undesired functional groups and the buildup of unintended multivariate frameworks. The synthesis of each framework was attempted via a direct synthetic method employing the appropriately functionalized biphenyldicarboxylate ligand. In general, this met with failure, which demonstrates the power and utility of postsynthetic methods for preparing new materials.

Purpose This paper aims to investigate the expatriate adjustment experiences of “biculturals”, defined here as individuals who have internalised at least two cultural profiles, in a host-country setting that is itself also culturally diverse. Design/methodology/approach A qualitative approach was adopted, involving semi-structured interviews with a small number of bicultural expatriates working in Malaysia. Findings The findings here echo previous studies in demonstrating bicultural expatriates’ ability (and tendency) to switch cultural frames as part of their adjustment. Despite this, however, their professional and social networks appear to still be shaped by cultural factors, with expatriates drawn towards networks whose members mainly comprise certain ethnic groups whose values and norms are perceived as being more closely aligned with those of the expatriate. Originality/value Though the literature on bicultural expatriates continues to grow, little emphasis has been given to a host-country setting that is itself culturally diverse. The findings here suggest that in such a setting, professional and social networks serve as an aid in the adjustment. Importantly, however, these networks, rather than being culturally impartial, as it were, may primarily comprise certain ethnic groups who are considered culturally “closer” to the expatriate in question.

A two-step Pd-catalyzed (3 + 2) cycloaddition/HNO2 elimination reaction sequence has been developed to give novel cyclic 1,3-dien-5-yne systems from Pd-stabilized zwitterionic 1,3-dipoles and 2-nitro-1,3-enyne substrates. The process is highly atom-efficient and tolerates the reaction of 2-vinyloxirane, 1-tosyl-2-vinylaziridine, and diethyl 2-vinylcyclopropane-1,1-dicarboxylate derived 1,3-dipoles with a variety of 2-nitro-1,3-enyne substrates. The stereochemistry of the intermediate (3 + 2) cycloadducts was determined by single crystal X-ray analysis. Furthermore, a selective kinetic elimination of the cycloadduct with an antiperiplanar relationship between the NO2 group and the participating hydrogen was demonstrated, allowing for efficient isolation of a single diastereoisomer of the cycloadduct.

It is demonstrated experimentally and confirmed theoretically that highly defective boron nitride showed outstanding performance for oxidative dehydrogenation of ethylbenzene. The catalyst is derived from carbon-doped hexagonal boron nitride nanosheets synthesized via a two-step reaction when participating the oxidative dehydrogenation reaction. The first step yields a polymeric precursor with the atomic positions of B, C, N relatively constrained, which is conducive for the formation of carbon atomic clusters uniformly dispersed throughout the BN framework. During the oxidative dehydrogenation of ethylbenzene to styrene, the nanoscale carbon clusters are removed and highly defective boron nitride (D-BN) is obtained, exposing boron-rich zigzag edges of BN that act as the catalytic sites. The catalytic performance of D-BN is therefore remarkably better than un-doped h-BN. Our results indicate that dispersed C-doping in h-BN is highly effective in terms of defect formation and resultant enhanced activity in oxidative dehydrogenation reactions.

The geometric and spectroscopic properties of four cationic

As hydrogen bonded frameworks are held together by relatively weak interactions, they often form several different frameworks under slightly different synthesis conditions and respond dynamically to stimuli such as heat and vacuum. However, these dynamic restructuring processes are often poorly understood. In this work, three isoreticular hydrogen bonded organic frameworks assembled through charge-assisted amidinium⋅⋅⋅carboxylate hydrogen bonds (1

Reactive inkjet printing was used for fast and facile spatially-controlled post-synthetic patterning of metal-organic framework films. Here, we report use of the reactive inkjet printing technique to rapidly produce patterned electroactive MOF films by covalent attachment of redox-responsive ferrocenyl groups to UiO-66-NH2 on FTO glass. This study paves the way for the wide applicability of reactive printing to MOF film modification.

The crystal structure of the natural product lawinal is reported. The compound crystallizes with monoclinic (I2) symmetry and with Z′ = 2., The structure of the natural product lawinal [systematic name: (−)-(2S)-5,7-dihy­droxy-6-methyl-4-oxo-2-phenyl­chromane-8-carbaldehyde, C17H14O5] at 150 K is reported. The compound crystallizes with monoclinic (I2) symmetry and with Z′ = 2. The absolute configuration could not be determined reliably from X-ray analysis only. However, our analysis returns the S-configuration at the C-2 position, consistent with previous stereochemical assignment from specific rotation. The independent mol­ecules form into alternating hydrogen-bonded chains with C—H⋯O=CH inter­molecular linkages that run parallel to the crystallographic a axis and are extended into the ac plane by π–π inter­actions between their phenyl substituents.

Earlier we reported the isolation of Goniotamirenone C [6-(2-chloro-1-hy­droxy-2-phenyl­eth­yl)-2H-pyran-2-one] from the leaf extracts of Goniothalamus tamirensis. Its gross structure was elucidated using NMR spectroscopic techniques and, on the basis of ECD calculations, the absolute configuration of this natural product was assigned as the syn isomer, (7S,8S)-Goniotamirenone C. In this paper we correct the structure of the natural product to the anti isomer from the semi-synthesis and single-crystal X-ray structure determination of (±)-Goniotamirenone C, which displays identical NMR spectroscopic data to the natural product., The structure of the racemic version of the natural product Goniotamirenone C [racemic anti-6-(2-chloro-1-hy­droxy-2-phenyl­eth­yl)-2H-pyran-2-one, C13H11ClO3] at 150 K is reported. The compound crystallizes with monoclinic (P21/n) symmetry and with Z′ = 2. One independent mol­ecule is ordered while the other independent mol­ecule exhibits an inter­esting whole-mol­ecule enanti­omeric disorder with occupancies of 0.846 (4) and 0.154 (4). The independent mol­ecules are hydrogen bonded with –OH⋯O=C linkages into chains that run parallel to the a axis. This structural analysis corrects our previous assignment as the syn isomer [Meesakul et al. (2020 ▸). Phytochemistry, 171, 112248–112255].

BACKGROUND: African Americans have low engagement in advance care planning (ACP). This has been attributed to healthcare distrust and skepticism about ACP. A better understanding of these attitudes is needed to address health disparities related to end-of-life care. OBJECTIVE: To explore the ACP-related values and beliefs of diverse African American communities across the USA and then the perceived value of an inexpensive end-of-life conversational game. DESIGN: Prospective, convergent, mixed methods cohort study involving fifteen underserved, African American communities across the USA. PARTICIPANTS: Of the 428 who attended events at purposively sampled sites, 90% consented to the research; 37% participated in one of 15 focus groups (n = 141). INTERVENTION: An end-of-life conversation game, played in groups of 4–6. MAIN MEASURES: The validated, 7-item ACP values and beliefs questionnaire (scaled 7 = least skeptical, 49 = most skeptical) was administered pre-game. Post-game focus groups explored perceptions about ACP and the intervention. KEY RESULTS: Participants had positive attitudes (low skepticism) about ACP with a median score of 12.00 (7.00, 20.00). Values and beliefs did not significantly differ by geographical region; however, rural areas were observed to be slightly more skeptical than urban areas (median score 14.00 vs. 11.00, p = 0.002). Themes from focus groups converged with survey data showing participants valued the ACP process and consider further engagement in ACP to be worthwhile. Subthemes emphasized the need for and value of ACP. CONCLUSIONS: Skepticism about ACP may contribute to low rates of ACP engagement in underserved African American communities. The positive attitudes uncovered in our study either negate previous findings or suggest reduced skepticism. TRIAL REGISTRATION: This study has been registered at clinicaltrials.gov (NCT03456921) ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11606-020-06224-z) contains supplementary material, which is available to authorized users.