Application of 2-pyridinyl thermolabile protecting groups (2-PyTPGs) for protection of hydroxyl, phosphate, and carboxyl functions is presented in this unit. Their characteristic feature is a unique removal process following the intramolecular cyclization mechanism and induced only by temperature rise. Deprotection rate of 2-PyTPGs is dependent on certain parameters, such as solvent (aqueous or non-aqueous medium), pH values, and electron distribution in a pyridine ring. The presented approach pertains not only to protecting groups but also to an advanced system of controlling certain properties of 2-pyridinyl derivatives. We improved the "chemical switch" method, allowing us to regulate the protecting group stability by inversing the electron distribution in 2-PyTPG. Together with pH values manipulation, this allows us to regulate the protecting group stability. Moreover, phosphite cyclization to oxazaphospholidine provides a very stable but easily reversible tool for phosphate protection/modifications. For all TPGs we confirmed their utility in a system of protecting groups. This concept can contribute to designing the general protecting group that could be useful in bioorganic chemistry. © 2017 by John Wiley & Sons, Inc.
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http://dx.doi.org/10.1002/cpnc.26 | DOI Listing |
Stroke
January 2025
Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China. (X.X., X.L., Y.P., Yufei Wei, Y.J., M.W., J.J., X.M., Yilong Wang, Yongjun Wang, L.L.).
Background: We performed a prespecified subgroup analysis of the CATIS-2 trial (China Antihypertensive Trial in Acute Ischemic Stroke II) to compare the effect of early versus delayed antihypertensive treatment on death and disability in patients with and without medical history of hypertension.
Methods: CATIS-2 is a multicenter randomized clinical trial conducted in 106 hospitals in China. The trial randomized 4810 patients with acute ischemic stroke within 24 to 48 hours of symptom onset and elevated systolic blood pressure between 140 and <220 mm Hg to receive antihypertensive treatment immediately after randomization or to discontinue antihypertensive medications for 7 days and then receive treatment on day 8.
Food Funct
January 2025
Nutrition Innovation Centre for Food and Health (NICHE), Ulster University, Coleraine, UK.
Impairment of gut barrier integrity is associated with the pathogenesis of gastrointestinal diseases, including inflammatory bowel disease, colorectal cancer, and coeliac disease. While many aspects of diet have been linked to improved barrier function, (poly)phenols, a broad group of bioactive phytochemicals, are of potential interest. The (poly)phenolic sub-class, flavan-3-ols, have been investigated in some detail owing to their abundance in commonly consumed foods, including grapes, tea, apples, cocoa, berries, and nuts.
View Article and Find Full Text PDFVet Res Forum
November 2024
Department of Comparative Biosciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Pulmonary fibrosis (PF) is a chronic interstitial lung disease with a progressive damage to the air sacs and deposition of collagen fibers in the lung tissue. The study aimed to explore the effects of oil (NSO) or thymoquinone (TQ), alone or in combination with dexamethasone (DEX), on the development of bleomycin (BLM)-induced PF. Forty-two male rats were divided into seven groups: Control (CTRL); BLM, received a single dose of BLM on day 0, intratracheally; all remaining groups received BLM, as well.
View Article and Find Full Text PDFJ Tradit Complement Med
January 2025
Immunomodulation of Natural Products Research Unit, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok 10330, Thailand.
Background And Aim: A critical causative factor of oxidative stress and inflammation leading to several skin complications is ultraviolet-B (UVB) irradiation. (LR), or tiger milk mushroom, is native to Southeast Asia. Cold water extract of an LR cultivar, TM02® (xLr®) is a promising anti-oxidant and anti-inflammatory source.
View Article and Find Full Text PDFJ Soc Cardiovasc Angiogr Interv
December 2024
Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
Background: Advancements in cardiac catheterization have improved survival for pediatric congenital heart disease patients, but the associated ionizing radiation risks necessitate ethical consideration.
Methods: This study presents an empirical model, developed from 3131 unique pediatric procedures, to establish alert levels based on a patient's lateral thickness of the thorax for various procedural categories during diagnostic or interventional cardiac catheterization. The model uses linear regression of logarithmic reference air kinetic energy released per unit mass (KERMA) and air KERMA area product, also referred to as dose area product, to set alert levels at the top 95% and 99% of patient data.
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