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Herein, we report an efficient three-component one-pot cascade protocol for the synthesis of pyrimidinone thiazole bifunctional hybrids in good yields. This transformation presumably occurs via in situ cyclocondensation of the 5-amino-pyrimidinones, a variety of aldehydes and thioglycolic acid. The optimized procedures are simple to operate, mild, and successful with a wide range of substrates. [ABSTRACT FROM AUTHOR]

Background: Measuring students' self‐regulation skills is essential to understand how they approach their learning tasks in order to identify areas where they might need additional support. Traditionally, self‐report questionnaires and think aloud protocols have been used to measure self‐regulated learning skills (SRL). However, these methods are based on students' interpretation, so they are prone to potential inaccuracy. Recently, there has been a growing interest in utilizing learning analytics (LA) to capture students' self‐regulated learning (SRL) by extracting indicators from their online trace data. Objectives: This paper aims to identify the indicators and metrics employed by previous studies to measure SRL in higher education. Additionally, the study examined how these measurements were validated. Methods: Following the protocol of Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA), this study conducted an analysis of 25 articles, published between 2015 and 2022, and sourced from major databases. Results and Conclusions: The results showed that previous research used a variety of indicators to capture learners' SRL. Most of these indicators are related to time management skills, such as indicators of engagement, regularity, and anti‐procrastination. Furthermore, the study found that the majority of the reviewed studies did not validate the proposed measurements based on any theoretical models. This highlights the importance of fostering closer collaboration between learning analytics and learning science to ensure the extracted indicators accurately represent students' learning processes. Moreover, this collaboration can enhance the validity and reliability of data‐driven approaches, ultimately leading to more meaningful and impactful educational interventions. Lay Description: What is already known about this topic?: Measuring students' self‐regulation skills is essential for understanding their learning approaches and identifying areas requiring further support.Traditionally, questionnaires and interviews have been used to measure learners' self‐regulation; however, these methods rely on students' own views, which can sometimes be unreliable.Recently, there has been more interest in using learning analytics to measure students' self‐regulation based on data extracted from their online activities. What this paper adds?: This paper systematically analyses how previous studies used learning analytics to measure students' self‐regulation in higher education.It examines how these measurements were validated. Implications for practise and/or policy: More collaboration is needed between researcher in learning science and learning analytics is essential to ensure that the metrics and methods developed are not only theoretically sound but also practically relevant. This collaboration ultimately contributes to the design of enhanced learning experiences and outcomes. [ABSTRACT FROM AUTHOR]

Alantolactone and isoalantolactone are two isomeric sesquiterpene lactones that were isolated from Innula recemosa. Here, we are used for the semisynthesis of novel isoxazolidine hybrids of alantolactone and isoalantolactone through a two-step process: nitrone synthesis followed by nitrone 1,3-dipolar cycloaddition. The formation of the cycloadduct was well characterized via modern spectroscopic techniques such as HRMS, 1 H NMR, 13 C NMR, DEPT-90, DEPT-135, and 2D NMR. This study also includes the synthesis of dinitrone with glyoxal and terephthalaldehyde, which is used for the dinitrone cycloadduct of alantolactone and isoalantolactone. Both nitrone cycloaddition and dinitrone cycloaddition proceed with high regio- and diastereoselectivity, resulting in the formation of only one isomer. The formation of the α-cycloadducts and the absolute configuration were established through 2D NMR and single-crystal X-ray diffraction analysis. The antimicrobial activity of all synthesized compounds was evaluated against a panel of Gram-positive and Gram-negative pathogens. Compounds 3f and 4f exhibited potential antimicrobial activity against drug-sensitive and -resistant Staphylococcus aureus strains, with minimum inhibitory concentrations ranging from 6 to 10 µM. A time-kill kinetics assay suggested that compounds 3f and 4f are bacteriostatic. Furthermore, scanning electron microscopy analysis confirmed that compounds 3f and 4f cause significant morphological alternations and exert potent antibacterial effects by causing substantial cellular damage., Competing Interests: Declaration of competing interest 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., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Toona ciliata , a member of the Meliaceae family, is valued for its high-quality timber and medicinal potential in treating various ailments. In this study, two triterpene isomers were isolated and characterised as an inseparable mixture from its chloroform extract using chromatography and spectroscopic techniques. Despite rigorous/extensive attempts to separate these isomers, they co-crystallised in a consistent 67:33 ratio, as verified by X-ray crystallography. The structure was further confirmed by ESI-MS, HRMS, 1 H NMR, 13 C NMR, DEPT 90, DEPT 135, COSY, NOESY, HSQC, and HMBC. Additionally, four more compounds were isolated successfully, out of that lutein and dyscusin C found for the first time from this plant.