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Cell replacement therapies for ocular diseases characterised by photoreceptors degeneration are challenging due to poor primary cell survival in culture. A stable retinal cell source to replace lost photoreceptors holds promise. Müller glia cells play a pivotal role in retinal homoeostasis by providing metabolic and structural support to retinal neurons, preventing aberrant photoreceptors migration, and facilitating safe glutamate uptake. In fish and amphibians, injured retinas regenerate due to Müller-like glial stem cells, a phenomenon absent in the mammalian retina for unknown reasons. Research on Müller cells has been complex due to difficulties in obtaining pure cell population and their rapid de-differentiation in culture. While various Müller glia cell lines from human and rats are described, no nonhuman primate Müller glia cell line is currently available. Here, we report spontaneously immortalised Müller glia cell lines derived from macaque neural retinas that respond to growth factors and expand indefinitely in culture. They exhibit Müller cells morphology, such as an elongated shape and cytoplasmic projections, express Müller glia markers (VIMENTIN, GLUTAMINE SYNTHASE, glutamate-aspartate transporter, and CD44), and express stem cell markers such as PAX6 and SOX2. In the presence of factors that induce photoreceptor differentiation, these cells show a shift in gene expression patterns suggesting a state of de-differentiation, a phenomenon known in reprogrammed mammalian Müller cells. The concept of self-renewing retina might seem unfeasible, but not unprecedented. While vertebrate Müller glia have a regeneration potential absent in mammals, understanding the mechanisms behind reprogramming of Müller glia in mammals could unlock their potential for treating retinal degenerative diseases., (© 2024 The Author(s). Journal of Cellular Physiology published by Wiley Periodicals LLC.)

The development of a safe, efficacious, and widely effective differentiation therapy for AML would dramatically improve the outlook for many patients worldwide. To this aim, our laboratory has discovered a class of differentiation agents that demonstrate tumour regression in murine models in vivo . Herein, we report a lead optimisation process around compound OXS007417, which led to improved potency, solubility, metabolic stability, and off-target toxicity of this compound class. A hERG liability was investigated and successfully alleviated through addition of nitrogen atoms into key positions of the compound. OXS008255 and OXS008474 demonstrated an improved murine PK profile in respect to OXS007417 and a delay in tumour growth in a subcutaneous in vivo model using HL-60 cells., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: A. J. R., T. A. M., S. G. D. and P. V. are founders and minor shareholders of OxStem Oncology, a subsidiary company of OxStem Ltd. G. M. W. is a minor shareholder of OxStem Ltd. At the time the work was conducted, A. J. R. and G. M. W. were paid consultant for OxStem Ltd. T. A. M. is currently a paid consultant for and minor shareholder of Dark Blue Therapeutics Ltd., (This journal is © The Royal Society of Chemistry.)

Children are valued in all societies although the specific framing of that value differs. Several societies frame the value of children through the lens of investment. For instance, children are worth having and financially and emotionally investing in because children may grow up to be economically productive citizens offering financial and emotional support to aging parents. Drawing on interviews with 18 Muslim participants in Aotearoa New Zealand, we show that the act of investing in children is emotional, financial and religious. However, while would-be-parents talked most strongly about children being a form of religious investment for the future, investment as money was forced upon participants as they engaged with assisted reproductive technologies (ARTs). We explore how Muslim women and couples navigate terrain around children as investment showing a tangible tension between investment as money and investment as accruing religious capital. We thus develop the concept of children as religious investment to better understand Muslims' journeys through ARTs., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

We describe the synthesis of trihydroxylated cyclohexane β-amino acids from (-)-shikimic acid, in their cis and trans configuration, and the incorporation of the trans isomer into a trans -2-aminocyclohexanecarboxylic acid peptide chain. Subsequently, the hydroxyl groups were partially or totally deprotected. The structural study of the new peptides by FTIR, CD, solution NMR and DFT calculations revealed that they all fold into a 14-helix secondary structure, similarly to the homooligomer of trans -2-aminocyclohexanecarboxylic acid. This means that the high degree of substitution of the cyclohexane ring of the new residue is compatible with the adoption of a stable helical secondary structure and opens opportunities for the design of more elaborate peptidic foldamers with oriented polar substituents at selected positions of the cycloalkane residues.

Acute myeloid leukaemia (AML) is an aggressive type of leukaemia with low rates of long-term survival. While the current standard of care is based on cytotoxic chemotherapy, a promising emerging approach is differentiation therapy. However, most current differentiating agents target specific mutations and are effective only in certain patient subtypes. To identify agents which may be effective in wider population cohorts, we performed a phenotypic screen with the myeloid marker CD11b and identified a compound series that was able to differentiate AML cell lines in vitro regardless of their mutation status. Structure-activity relationship studies revealed that replacing the formamide and catechol methyl ether groups with sulfonamide and indazole respectively improved the in vitro metabolic profile of the series while maintaining the differentiation profile in multiple cell lines. This optimisation exercise enabled progression of a lead compound to in vivo efficacy testing. Our work supports the promise of phenotypic screening to identify novel small molecules that induce differentiation in a wide range of AML subtypes., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: A.J.R., T.A.M., S.G.D. and P.V. are founders and minor shareholders of OxStem Oncology, a subsidiary company of OxStem Ltd. A.J.R. is a paid consultant for OxStem Ltd. G.M.W. is a paid consultant for and minor shareholder of OxStem Ltd. T.A.M. is currently a paid consultant for and minor shareholder of Dark Blue Therapeutics Ltd., (Copyright © 2023. Published by Elsevier Masson SAS.)

The synthesis of a range of loline alkaloids is reported. The C(7) and C(7a) stereogenic centers for the targets were formed by the established conjugate addition of lithium ( S )- N -benzyl- N -(α-methylbenzyl)amide to tert -butyl 5-benzyloxypent-2-enoate, ensuing enolate oxidation to give an α-hydroxy-β-amino ester, and then formal exchange of the resultant amino and hydroxyl functionalities (via the intermediacy of the corresponding aziridinium ion) to give an α-amino-β-hydroxy ester. Subsequent transformation gave a 3-hydroxyprolinal derivative which was converted to the corresponding N - tert -butylsulfinylimine. Mannich-type reaction with the enolate derived from O -Boc protected methyl glycolate then formed the remaining C(1) and C(2) stereogenic centers for the targets. The 2,7-ether bridge was formed by a displacement reaction, completing construction of the loline alkaloid core. Facile manipulations then gave a range of loline alkaloids, including loline itself.

Retinal astrocytes are vital for neuronal homeostasis in the retina. Together with Müller glia, they provide retinal cells with neurotrophic factors, antioxidative support, and defense mechanisms such as the formation of the blood-retinal barrier. Substantial heterogeneity of astrocyte morphology and function represents a challenge for identification of distinct subtypes which may be potential targets for therapeutic purposes. Hence, identification of novel markers of astrocyte subpopulations is highly relevant to better understand the molecular mechanisms involved in retinal development, homeostasis, and pathology. In this study, we observed that the cell cycle regulator, p16 INK4a , is expressed in immature astrocytes in the mouse retina. Immunohistochemical analysis showed p16 INK4a expression in the optic nerve of wild-type mice from 3 days to 3 months of age and in the nerve fiber layer of the adult mouse retina. Colocalization of p16 INK4a expression and glial fibrillary acidic protein (immature/mature astrocyte marker) tends to decrease with age. However, colocalization of p16 INK4a expression and vimentin (immature astrocyte marker) remains high in the optic nerve from the early postnatal period to adulthood. The observations from this study provide a valuable tool for further investigations of ocular astrocytes in the developing retina as well as in degenerative retinopathies.

Background: Many public health experts have claimed that elimination strategies of pandemic response allow 'normal social life' to resume. Recognizing that social connections and feelings of normality are important for public health, this study examines whether, and for whom, that goal is realized, and identifies obstacles that may inhibit its achievement., Methods: Thematic analysis of narratives obtained via a qualitative cross-sectional survey of a community cohort in Aotearoa | New Zealand., Results: A majority of participants reported that life after elimination was 'more or less the same' as before the pandemic. Some became more social. Nevertheless, a sizeable minority reported being less social, even many months after elimination. Key obstacles to social recovery included fears that the virus was circulating undetected and the enduring impact of lockdowns upon social relationships, personal habits and mental health. Within our sample, old age and underlying health conditions were both associated with a propensity to become less social., Conclusions: Elimination strategies can successfully allow 'normal social life' to resume. However, this outcome is not guaranteed. People may encounter difficulties with re-establishing social connections in Zero-COVID settings. Measures designed to overcome such obstacles should be an integral part of elimination strategies., (© The Author(s) 2022. Published by Oxford University Press on behalf of Faculty of Public Health.)

Background The COVID-19 pandemic continues to devastate communities all over the world. The aim of this study was to evaluate the efficacy and safety of the test agent as a prophylaxis against SARS-CoV-2 infection in a population of high-risk healthcare workers. Methods The study was a multi-centre, prospective, double blind, randomized, placebo-controlled trial. Key eligibility criteria included absence of significant co-morbidity and no previous SARS-CoV-2 infection or vaccination. Participants were randomised to either the active agent nasal spray or placebo using computer generated random number tables. The nasal spray was administered 3 times daily over a 45 day course. The primary end point was the percentage of subjects who tested positive for IgGS (anti-spike, immunoglobulin G specific to the spike protein of SARS-CoV-2) at day 45. Results Between 16th April 2021 and 26th July 2021, 556 participants were analysed for the primary endpoint (275 Test; 281 Placebo). The test agent significantly reduced SARS-CoV-2 infection compared to placebo [36 cases (13.1%) Vs 97 cases (34.5%); OR 0.29 (95% CI; 0.18-0.45), p < 0.0001]. Fewer clinical symptoms were also seen in the test group [57 cases (17.6%) vs 112 cases (34.6%); OR 0.40, (95% CI; 0.27-0.59), p < 0.0001]. No harmful effects were associated with taking the test agent. Conclusion The test agent significantly reduced SARS-CoV-2 infection in healthcare workers, with 62% fewer infections when compared to placebo. It was found to be safe and well tolerated and offers a novel treatment option for prophylaxis against SARS-CoV-2 infection., Competing Interests: Declaration of Competing Interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. JAS, LS, AD, KED, SGD, MAM, AM, RM, DR, AJR, and RU are shareholders of Raphael Labs LTD. JS is the managing director of Swales Pharma Consulting providing consulting services for a range of pharmaceutical companies. AJM and AR sit on the advisory board of Raphael labs., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

A therapeutic approach that holds the potential to treat all Duchenne muscular dystrophy (DMD) patient populations is utrophin modulation. Ezutromid, a first generation utrophin modulator which was later found to act via antagonism of the arylhydrocarbon receptor, progressed to Phase 2 clinical trials. Although interim data showed target engagement and functional improvements, ezutromid ultimately failed to meet its clinical endpoints. We recently described the identification of a new class of hydrazide utrophin modulators which has a different mechanism of action to ezutromid. In this study we report our early optimisation studies on this hydrazide series. The new analogues had significantly improved potency in cell-based assays, increased sp 3 character and reduced lipophilicity, which also improved their physicochemical properties. A representative new analogue combining these attributes increased utrophin protein in dystrophic mouse cells showing it can be used as a chemical tool to reveal new insights regarding utrophin upregulation as a strategy for DMD therapeutic intervention., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Shortly after the COVID-19 pandemic reached Aotearoa New Zealand, stringent lockdown measures lasting 7 weeks were introduced to manage community spread of the virus. This paper reports the findings of a qualitative study examining how lockdown measures impacted upon the lives of nurses, midwives and personal care assistants caring for community-based patients during this time. The study involved nationwide surveys and in-depth interviews with 15 registered nurses employed in community settings, two community midwives and five personal care assistants. During the lockdown, nurses, midwives and personal care assistants working in the community showed considerable courage in answering their 'call to duty' by taking on heightened care responsibilities and going 'the extra mile' to help others. They faced significant risks to personal and professional relationships when they were required to take on additional and complex responsibilities for community-based patients. Despite the hypervigilant monitoring of their personal protective equipment (PPE), the need to safeguard family and community members generated considerable stress and anxiety. Many also faced personal isolation and loneliness as a result of lockdown restrictions. Moreover, the negative impacts of experiences during lockdown often continued to be felt once restrictions had been lifted, inflecting life during periods in which community transmission of COVID-19 was not occurring. This article makes five core service delivery and policy recommendations for supporting community-based nurses, midwives and personal care assistants in respiratory disease pandemics: acknowledging the crucial role played by community-based carers and the associated stress and anxiety they endured by championing respect and compassion; demystifying the 'heroism' or 'self-sacrifice' projected onto care workers; the timely provision of adequate protective equipment; improving remuneration, with adequate provision for time off; and regular counselling, peer support groups and education on work-life balance delivered by support workers in recognition of stressors arising from these complex and isolated working conditions., (© 2022 John Wiley & Sons Ltd.)

The first asymmetric synthesis of microgrewiapine C, a piperidine alkaloid isolated from Microcos paniculata , is reported. This synthesis prompted correction of the 1 H and 13 C NMR data for the natural sample of the alkaloid, which was achieved by reanalysis of the original spectra. The corrected data for the natural product were found to be identical to those of the synthetic sample prepared herein, thus confirming the structural and relative configurational assignment of microgrewiapine C. Although comparison of specific rotation values indicates that the (1 R ,2 S ,3 S ,6 S ) absolute configuration should be assigned to the alkaloid, consideration of potential common biosynthetic origins of microgrewiapine C and congeners suggests that further phytochemical investigations are warranted.

Despite much progress in developing better drugs, many patients with acute myeloid leukemia (AML) still die within a year of diagnosis. This is partly because it is difficult to identify therapeutic targets that are effective across multiple AML subtypes. One common factor across AML subtypes is the presence of a block in differentiation. Overcoming this block should allow for the identification of therapies that are not dependent on a specific mutation for their efficacy. Here, we used a phenotypic screen to identify compounds that stimulate differentiation in genetically diverse AML cell lines. Lead compounds were shown to decrease tumor burden and to increase survival in vivo . Using multiple complementary target deconvolution approaches, these compounds were revealed to be anti-mitotic tubulin disruptors that cause differentiation by inducing a G2-M mitotic arrest. Together, these results reveal a function for tubulin disruptors in causing differentiation of AML cells., Competing Interests: During the course of this study, A.O’M. was an employee of Eurofins Discovery. S.G.D, P.V., A.J.R. and T.A.M. are all founding shareholders of OxStem Oncology Limited (OSO), a subsidiary company of OxStem Limited. G.M.W. and G.C.T. are former employees of OxStem. G.C.T. is a current employee of Cambrian Biopharma. L.M.K. is an employee of Axis Bioservices Limited. T.A.M. is a consultant and shareholder of Dark Blue Therapeutics., (© 2022 The Author(s).)

The formation of O -acetyl microgrewiapine A is investigated. NMR data for the authentic sample derived from the natural product are corrected. Wholly synthetic samples, produced from reductive N -methylation of synthetic microcosamine A (to give synthetic microgrewiapine A) followed by O -acetylation, exhibit NMR data that are identical to those of the authentic sample. The previous report that this two-step transformation proceeds with epimerization at C-6 is thus shown to be in error: the purported sample of O -acetyl 6- epi -microgrewiapine A is structurally misassigned and is, in fact, O -acetyl microgrewiapine A. A plausible rationale for the structural misassignment is advanced.

Background: Women living with HIV in Indonesia encounter challenging obstacles to healthcare, which is exacerbated by COVID-19. Access is difficult as there are limited numbers of poorly supported healthcare providers. Women also face significant stigma when disclosing their HIV-status., Objectives: Our main purpose is to give a voice to disempowered women living with HIV, by normalising the discussion of HIV, to empower health professionals to better understand the issues faced by women living with HIV, and develop improved treatment practices., Design: Our project was guided by a Feminist Participatory Action Research (FPAR) framework. FPAR refers to 'a participatory and action-oriented approach to research that centres gender and women's experiences both theoretically and practically'. It creates meaningful participation for women throughout the research process, ensuring a collective critical consciousness that challenges oppressive attitudes, beliefs, and practices that may be deeply embedded in society., Method: Purposive sampling and a thematic analysis was applied to focus group discussions with 20 women living with HIV and 20 women without HIV in Palembang, South Sumatra., Results: When women living with HIV face a difficult decision, do they disclose their status knowing that they may face stigma and even a refusal to be treated; or do they conceal their status and face not receiving the right care? In this article, we explore the stories of women living with HIV as they seek medical treatment during the COVID-19 pandemic. We show that there is no optimal solution for women as they lose whether they disclose their HIV status or not., Conclusion: Women's stories around HIV and COVID-19 intersect with conditions such as poverty and discrimination, as well as embedded gender systems, creating overlapping barriers to treatment. Government must challenge this culture by introducing a comprehensive sex and HIV education programme. This would normalise discussions of HIV-related topics, leading to improved health outcomes., Competing Interests: Conflict of interest statement: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2021.)

Induction of differentiation is a promising therapeutic strategy against acute myeloid leukemia. However, current differentiation therapies are effective only to specific patient populations. To identify novel differentiation agents with wider efficacy, we developed a phenotypic high-throughput screen with a range of genetically diverse cell lines. From the resulting hits, one chemical scaffold was optimized in terms of activity and physicochemical properties to yield OXS007417, a proof-of-concept tool compound, which was also able to decrease tumor volume in a murine in vivo xenograft model.

Acute myeloid leukemia (AML) is the most aggressive type of blood cancer, and there is a continued need for new treatments that are well tolerated and improve long-term survival rates in patients. Induction of differentiation has emerged as a promising alternative to conventional cytotoxic chemotherapy, but known agents lack efficacy in genetically distinct patient populations. Previously, we established a phenotypic screen to identify small molecules that could stimulate differentiation in a range of AML cell lines. Utilising this strategy, a 1,5-dihydrobenzo[ e ][1,4]oxazepin-2(3 H )-one hit compound was identified. Herein, we report the hit validation in vitro, structure-activity relationship (SAR) studies and the pharmacokinetic profiles for selected compounds.

Duchenne muscular dystrophy is a fatal disease with no cure, caused by lack of the cytoskeletal protein dystrophin. Upregulation of utrophin, a dystrophin paralogue, offers a potential therapy independent of mutation type. The failure of first-in-class utrophin modulator ezutromid/SMT C1100 in Phase II clinical trials necessitates development of compounds with better efficacy, physicochemical and ADME properties and/or complementary mechanisms. We have discovered and performed a preliminary optimisation of a novel class of utrophin modulators using an improved phenotypic screen, where reporter expression is derived from the full genomic context of the utrophin promoter. We further demonstrate through target deconvolution studies, including expression analysis and chemical proteomics, that this compound series operates via a novel mechanism of action, distinct from that of ezutromid., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: R.J.F., S.G.D., A.J.R. and K.E.D are minor shareholders of Summit Therapeutics plc., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)

Enantiorecognition between a racemic reagent and a racemic substrate can be a valuable process in organic synthesis. This review highlights representative examples of this phenomenon and the use of mutual kinetic resolution as a method for screening of kinetic and/or parallel kinetic resolutions.

Indonesia's 2014 health reforms advocated for universal health coverage for all Indonesians. The reforms made provision for integrated human immunodeficiency virus (HIV) programmes, with testing available at community health centres and hospitals for pregnant women and women of childbearing age. The question remains, though, as to whether testing has been effective. This article focuses on barriers women face accessing HIV testing and presents findings from the experiences of 18 HIV-positive women. To triangulate findings, interviews were conducted with 26 health workers, 9 non-governmental organisation workers and 12 HIV stakeholders. The article examines barriers to pregnant women's access to HIV tests, showing that barriers relate to women not having reproductive health rights. It highlights reproductive rights noted in the Respectful Maternity Care Charter, and violations to them relevant to HIV testing in pregnancy. Five reported rights violations include: women being unable to access information; being unable to make informed decisions; having no right to confidentiality and privacy; experiencing ongoing discrimination; and having no right to timely HIV testing. The failure of Indonesia to protect these rights contributes to women being denied HIV testing. Findings show the need for increased HIV testing services for pregnant women and assert that health personnel and programme policy-makers need to be held accountable for the protection and fulfilment of women's rights in respect of HIV testing. The findings show that policy makers must make changes to ensure health services improve, health professionals must be better trained, and women's socio-cultural and political contexts must be considered.

In 2014, Indonesia reinvigorated its commitment to the provision of a universal health care system by introducing the National Health Insurance Program ( Jaminan Kesehatan Nasional , JKN), with the aim of increasing access to health care for all sectors of society. A key question that emerges in the current climate is: how can Indonesia ensure people can access HIV health care? This question is critically important given Indonesia is on the verge of passing a law criminalising all sex outside of marriage. If passed, anyone presenting with HIV will be suspected ipso facto of involvement in criminal activity (e.g. them or their partner having sex outside of marriage and/or using intravenous drugs). In this environment, preventing transmission of HIV from mother to child becomes more difficult. In exploring these issues, we argue that, in a time of populist morality, Indonesia must give significant attention to how universal health coverage can prevent HIV transmission, particularly from mother to child. We offer three key strategies for Indonesia to implement in this regard: removing health care provision from a moral framework; de-idealising the category of woman; and repositioning shame and stigma around HIV.

We have previously reported the discovery of a series of rhodanine-based inhibitors of the PIM family of serine/threonine kinases. Here we described the optimisation of those compounds to improve their physicochemical and ADME properties as well as reducing their off-targets activities against other kinases. Through molecular modeling and systematic structure activity relationship (SAR) studies, advanced molecules with high inhibitory potency, reduced off-target activity and minimal efflux were identified as new pan-PIM inhibitors. One example of an early lead, OX01401, was found to inhibit PIMs with nanomolar potency (15 nM for PIM1), inhibit proliferation of two PIM-expressing leukaemic cancer cell lines, MV4-11 and K562, and to reduce intracellular phosphorylation of a PIM substrate in a concentration dependent manner., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Utrophin modulation is a disease-modifying therapeutic strategy for Duchenne muscular dystrophy that would be applicable to all patient populations. To improve the suboptimal profile of ezutromid, the first-in-class clinical candidate, a second generation of utrophin modulators bearing a phosphinate ester moiety was developed. This modification significantly improved the physicochemical and ADME properties, but one of the main lead molecules was found to have dose-limiting hepatotoxicity. In this work we describe how less lipophilic analogues retained utrophin modulatory activity in a reporter gene assay, upregulated utrophin protein in dystrophic mouse muscle cells, but also had improved physicochemical and ADME properties. Notably, ClogP was found to directly correlate with pIC 50 in HepG2 cells, hence leading to a potentially safer toxicological profiles in this series. Compound 21 showed a balanced profile (H2K EC 50 : 4.17 μM, solubility: 477 μM, mouse hepatocyte T 1/2 > 240 min) and increased utrophin protein 1.6-fold in a Western blot assay., Competing Interests: The authors declare the following competing financial interest(s): S.H. and F.X.W. are or were Summit Therapeutics plc employees or consultants at the time that the work was conducted. K.E.D., S.G.D. and A.J.R. are minor shareholders of Summit Therapeutics plc., (© 2020 American Chemical Society.)

Utrophin modulation is a promising therapeutic strategy for Duchenne muscular dystrophy (DMD), which should be applicable to all patient populations. Following on from ezutromid, the first-generation utrophin modulator, we describe the development of a second generation of utrophin modulators, based on the bioisosteric replacement of the sulfone group with a phosphinate ester and substitution of the metabolically labile naphthalene with a haloaryl substituent. The improved physicochemical and absorption, distribution, metabolism, and excretion (ADME) properties, further reflected in the enhanced pharmacokinetic profile of the most advanced compounds, 30 and 27 , led to significantly better in vivo exposure compared to ezutromid and alleviation of the dystrophic phenotype in mdx mice. While 30 was found to have dose-limiting hepatotoxicity, 27 and its enantiomers exhibited limited off-target effects, resulting in a safe profile and highlighting their potential utility as next-generation utrophin modulators suitable for progression toward a future DMD therapy.

Purpose: Age-related macular degeneration leads to retinal pigment epithelium (RPE) cell death and loss of central vision. In vivo studies have shown that the RPE layer has an innate, but limited, ability to repopulate atrophic areas. We aimed to establish a semiautomated, in vitro , wound healing assay workflow for targeted screening of compounds able to influence RPE wound healing. Methods: The ARPE-19 phenotype was evaluated using bright-field microscopy, immunocytochemistry, and quantitative real-time polymerase chain reaction. ARPE-19 monolayers were simultaneously scratched in a 96-well format and treated with Hoechst-33342 and an array of compounds. Initial wound dimensions and wound healing were subsequently evaluated using the EVOS FL Auto 2.0 imaging platform combined with automated image analyses. Results: Long-term cultured ARPE-19 cells displayed a more in vivo RPE-like phenotype compared with recently seeded or short-term cultured cells. No statistical difference of initial scratch width was observed between short-term and long-term cultured cells, but more wells were excluded from analyses in total in the latter case due to scratch width, scratch smoothness, and imaging errors. Furthermore, the previous time spent in continuous culture had an effect on the observation of an altered wound healing response to different treatment conditions. Conclusions: We have established a semiautomated, 96-well format, in vitro wound healing assay with a reproducible workflow. This would enable screening of a significant number of compounds and greatly advances the potential of identifying novel therapeutics that may enhance the innate ability of RPE cells to repopulate atrophic areas.

5-(Ethylsulfonyl)-2-(naphthalen-2-yl)benzo[ d ]oxazole (ezutromid, 1 ) is a first-in-class utrophin modulator that has been evaluated in a phase 2 clinical study for the treatment of Duchenne muscular dystrophy (DMD). Ezutromid was found to undergo hepatic oxidation of its 2-naphthyl substituent to produce two regioisomeric 1,2-dihydronaphthalene-1,2-diols, DHD1 and DHD3, as the major metabolites after oral administration in humans and rodents. In many patients, plasma levels of the DHD metabolites were found to exceed those of ezutromid. Herein, we describe the structural elucidation of the main metabolites of ezutromid, the regio- and relative stereochemical assignments of DHD1 and DHD3, their de novo chemical synthesis, and their production in systems in vitro. We further elucidate the likely metabolic pathway and CYP isoforms responsible for DHD1 and DHD3 production and characterize their physicochemical, ADME, and pharmacological properties and their preliminary toxicological profiles.

Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disease arising from mutations in the dystrophin gene. Upregulation of utrophin to compensate for the missing dystrophin offers a potential therapy independent of patient genotype. The first-in-class utrophin modulator ezutromid/SMT C1100 was developed from a phenotypic screen through to a Phase 2 clinical trial. Promising efficacy and evidence of target engagement was observed in DMD patients after 24 weeks of treatment, however trial endpoints were not met after 48 weeks. The objective of this study was to understand the mechanism of action of ezutromid which could explain the lack of sustained efficacy and help development of new generations of utrophin modulators. Using chemical proteomics and phenotypic profiling we show that the aryl hydrocarbon receptor (AhR) is a target of ezutromid. Several lines of evidence demonstrate that ezutromid binds AhR with an apparent K D of 50 nm and behaves as an AhR antagonist. Furthermore, other reported AhR antagonists also upregulate utrophin, showing that this pathway, which is currently being explored in other clinical applications including oncology and rheumatoid arthritis, could also be exploited in future DMD therapies., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Following on from ezutromid, the first-in-class benzoxazole utrophin modulator that progressed to Phase 2 clinical trials for the treatment of Duchenne muscular dystrophy, a new chemotype was designed to optimise its physicochemical and ADME profile. Herein we report the synthesis of SMT022357, a second generation utrophin modulator preclinical candidate, and an asymmetric synthesis of its constituent enantiomers. The pharmacological properties of both enantiomers were evaluated in vitro and in vivo . No significant difference in the activity or efficacy was observed between the two enantiomers; activity was found to be comparable to the racemic mixture., (© 2019 The Authors.)

Colossal permittivity materials exhibit extreme polarization in an applied electric field, providing applications in electronics and energy transmission. Understanding the atomic-scale mechanism behind colossal permittivity remains a challenging task and is key to optimizing materials with this property. The fundamental mechanism of colossal permittivity is reported and, using CaCu 3 Ti 4 O 12 as an example, it is attributed to the formation of an unusual metallic interface between the grain and grain boundary materials (CaCu 3 Ti 4 O 12 and Cu x O (x = 1, 2), respectively), not created by oxygen vacancies as is normally the case in oxide materials. This metallic layer around the grain forms confined shells of charge that pool on one side when under an applied field, which results in colossal permittivity. A route towards enhancing colossal permittivity is explained by means of manipulating the interface properties, as well as altering sample geometries. A methodology to artificially engineer colossal permittivity metamaterials is also shown., (© 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A method to enable the synthesis of conduramines and their N -substituted derivatives (enantiopure or racemic form) in six steps (five steps for N -substituted derivatives) from cyclohexa-1,4-diene is reported. Key features of this reaction sequence include a preparation of benzene oxide that is amenable to multigram scale, and its efficient ring-opening upon treatment with a primary amine. Epoxidation of the resultant amino alcohols (40% aq HBF 4 then m -CPBA) is accompanied by hydrolytic ring-opening in situ to give the corresponding N -substituted conduramine derivatives directly. These may undergo subsequent N -deprotection to give the parent conduramines, as demonstrated by the preparation of enantiopure (-)-conduramine A1, (-)-conduramine A2, and (-)-conduramine E2 (the latter two for the first time). The selectivity of the epoxidation reaction is proposed to be the result of competitive ammonium-directed and hydroxyl-directed epoxidation processes, followed by either direct (S N 2-type) or conjugate (S N 2'-type) ring-openings of the intermediate epoxides.

The reported characterization data for the allocolchicinoid alkaloid suhailamine, isolated from Colchicum decaisnei and known to have an erroneous structure, have been reanalyzed. This analysis has led to the current proposal that suhailamine has the same structure as N -acetylcolchinol methyl ether (NCME), an assertion that is supported by comparison with previously reported data for NCME. Suhailamine is therefore a phantom natural product, while NCME represents a naturally occurring allocolchicinoid rather than a purely synthetic entity.

The SuperQuat (4-substituted 5,5-dimethyloxazolidine-2-one) family of chiral auxiliaries was first developed by us in the 1990s to address the shortcomings of the Evans (4-substituted oxazolidin-2-one) family of chiral auxiliaries. The incorporation of geminal dimethyl substitution at C(5) has two effects: (i) it induces a conformational bias on an adjacent, otherwise conformationally labile C(4)-substituent so that it projects towards the N-acyl fragment, thus offering superior diastereofacial selectivity in a range of transformations; and (ii) it hinders nucleophilic attack at the endocyclic carbonyl group, facilitating recovery and recyclability of the auxiliary, with enhanced cleavage properties. This review summarises the development and some of the most common uses of the SuperQuat family of chiral auxiliaries, particularly in the synthesis of natural products or other targets having bioloigcal interest. Where possible, comparisons with the performances of the corresponding Evans auxiliaries are presented.

The asymmetric syntheses of all members of the Hancock alkaloid family based upon a 2-substituted N-methyl-1,2,3,4-tetrahydroquinoline core are delineated. The conjugate addition of enantiopure lithium N-benzyl- N-(α-methyl- p-methoxybenzyl)amide to 5-( o-bromophenyl)- N-methoxy- N-methylpent-2-enamide is used to generate the requisite C-2 stereogenic center of the targets, while an intramolecular Buchwald-Hartwig coupling is used to form the 1,2,3,4-tetrahydroquinoline ring. Late-stage diversification completes construction of the C-2 side chains. Thus, (-)-cuspareine, (-)-galipinine, (-)-galipeine, and (-)-angustureine were prepared in overall yields of 30%, 28%, 15%, and 39%, respectively, in nine steps from commercially available 3-( o-bromophenyl)propanoic acid in all cases. Unambiguously corrected 1 H and 13 C NMR data for the originally isolated samples of (-)-cuspareine, (-)-galipinine, and (-)-angustureine are also reported, representing a valuable reference resource for these popular synthetic targets.

Epoxidations (40% aq HBF 4 then m-CPBA) of racemic cis-2-( N-benzylamino)cyclohex-3-en-1-ol and racemic cis-2-( N, N-dibenzylamino)cyclohex-3-en-1-ol proceed with very high levels of diastereoselectivity (>95:5 dr). The latter is in direct contrast to the epoxidation of the corresponding trans-diastereoisomer (which proceeds with essentially no selectivity), showing that the relative configuration of the substrate dramatically influences the diastereoselectivity in these instances. Meanwhile, epoxidations of enantiopure (1 R,2 S,α R)-2-[( N-α-methylbenzyl)amino]cyclohex-3-en-1-ol and (1 S,2 R,α R)-2-[( N-α-methylbenzyl)amino]cyclohex-3-en-1-ol [surrogates for the enantiomers of cis-2-( N-benzylamino)cyclohex-3-en-1-ol] proceed with complete diastereoselectivity (>95:5 dr) under the same conditions, showing that neither the presence of the α-methyl group nor the relative configuration of the α-methylbenzyl stereocenter have an effect upon the established level of diastereoslectivity in these cases. In contrast, epoxidations of enantiopure (1 R,2 S,α R)-2-[ N-benzyl- N-(α-methylbenzyl)amino]cyclohex-3-en-1-ol and (1 S,2 R,α R)-2-[ N-benzyl- N-(α-methylbenzyl)amino]cyclohex-3-en-1-ol [surrogates for the enantiomers of cis-2-( N, N-dibenzylamino)cyclohex-3-en-1-ol] proceed with lower diastereoselectivity (∼70:30 dr). Thus, the presence of the α-methyl group has a detrimental effect on the established level of diastereoselectivity in these cases (although again the relative configuration of the α-methylbenzyl stereocenter is unimportant). The diastereoselective epoxidation pathway is used to enable the asymmetric syntheses of six hitherto unknown, enantiopure dihydroconduramines (+)-C-2, (-)-C-2, (+)-D-2, (+)-E-2, (+)-F-2, and (-)-F-2 (>99% ee in each case).

Two synthetic routes have been developed for the asymmetric syntheses of (2 R,3 S)- and (2 S,3 S)-3-hydroxyproline. The key synthetic step in each of these strategies is the conversion of protected α,δ-dihydroxy-β-amino esters (either 2,3- anti- or 2,3- syn-configured) into β,δ-dihydroxy-α-amino esters (protected forms thereof), via the intermediacy of the corresponding aziridinium ions. The products of these stereospecific rearrangements were then cyclized and deprotected to afford (2 R,3 S)-3-hydroxyproline and (2 S,3 S)-3-hydroxyproline as single diastereoisomers (>99:1 dr) in >26% overall yield.

The asymmetric syntheses of a range of N- and O-protected 3-deoxy-3-aminosphingoid bases have been achieved using two complementary approaches. dl-Serine was converted to a racemic N,N-dibenzyl-protected γ-amino-α,β-unsaturated ester which was resolved using a parallel kinetic resolution (PKR) strategy upon reaction with a pseudoenantiomeric mixture of lithium (R)-N-benzyl-N-(α-methylbenzyl)amide and lithium (S)-N-3,4-dimethoxybenzyl-N-(α-methylbenzyl)amide, giving the corresponding enantio- and diastereoisomerically pure β,γ-diamino esters. Alternatively, elaboration of l-serine gave the corresponding enantiopure N,N-dibenzyl-protected γ-amino-α,β-unsaturated ester, and doubly diastereoselective conjugate addition of the antipodes of lithium N-benzyl-N-(α-methylbenzyl)amide was found to proceed under the dominant stereocontrol of the lithium amide reagent in both cases, thus augmenting the accessible range of β,γ-diamino esters. Both of these protocols were expanded to include in situ oxidation of the enolate formed upon conjugate addition, giving access to the corresponding α-hydroxy-β,γ-diamino esters. Elaboration of these β,γ-diamino and α-hydroxy-β,γ-diamino esters gave the protected forms of the 3-deoxy-3-aminosphingoid base targets.

The 1 H and 13 C NMR data of synthetic samples of (S)-N(1)-methyl-2-[2'-(3″-hydroxy-4″-methoxyphenyl)ethyl]-1,2,3,4-tetrahydroquinoline, the originally proposed structure of the Hancock alkaloid (-)-galipeine, do not match those of the natural product. Herein, the preparation of the regioisomer (S)-N(1)-methyl-2-[2'-(3″-methoxy-4″-hydroxyphenyl)ethyl]-1,2,3,4-tetrahydroquinoline is reported, the 1 H and 13 C NMR data of which are in excellent agreement with those of (-)-galipeine. Comparison of specific rotation data enables assignment of the absolute (S)-configuration of the alkaloid, and together, these data engender the structural revision of (-)-galipeine to (S)-N(1)-methyl-2-[2'-(3″-methoxy-4″-hydroxyphenyl)ethyl]-1,2,3,4-tetrahydroquinoline.

The diastereoselectivities and rates of epoxidation (upon treatment with Cl 3 CCO 2 H then m-CPBA) of a range of cis- and trans-4-aminocycloalk-2-en-1-ol derivatives (containing five-, six-, and seven-membered rings) have been investigated. In all cases where the two potential directing groups can promote epoxidation on opposite faces of the ring scaffold, evidence of competitive epoxidation pathways, promoted by hydrogen-bonding to either the in situ formed ammonium moiety or the hydroxyl group, was observed. In contrast to the relative directing group abilities already established for the six-membered ring system (NHBn ≫ OH > NBn 2 ), an N,N-dibenzylammonium moiety appeared more proficient than a hydroxyl group at directing the stereochemical course of the epoxidation reaction in a five- or seven-membered system. In the former case, this was rationalized by the drive to minimize torsional strain in the transition state being coupled with assistance from hydrogen-bonding to the ammonium moiety. In the latter case, this was ascribed to the steric bulk of the ammonium moiety disfavoring conformations in which hydrogen-bonding to the hydroxyl group results in direction of the epoxidation to the syn face. In cases where the two potential directing groups can promote epoxidation on the same face of the ring scaffold, an enhancement of epoxidation diastereoselectivity was not observed, while introduction of a second, allylic heteroatom to the substrate results in diminishment of the rate of epoxidation in all cases. Presumably, reduction of the nucleophilicity of the olefin by the second, inductively electron-withdrawing heteroatom is the dominant factor, and any assistance to the epoxidation reaction by the potential to form hydrogen-bonds to two directing groups rather than one is clearly unable to overwhelm it.