A mild and stereoconvergent synthesis of 1alpha,25-dihydroxyvitamin D(3) (calcitriol, 1a) is described. The key step is a cascade process consisting of two consecutive transformations: An initial palladium-catalyzed 6-exo-cyclocarbopalladation of vinyl triflate 4 followed by a Negishi cross-coupling reaction with alkenyl zinc 3. This approach is of interest for the rapid synthesis of a variety of new vitamin D(3) analogues of therapeutic potential, especially those modified at the triene and ring-A. The mildness of the method also allows the preparation of thermal sensitive vitamin D(3) analogues.
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http://dx.doi.org/10.1016/j.jsbmb.2006.12.026 | DOI Listing |
Free Radic Res
January 2025
Department of Biochemistry, Faculty of Medicine, Marmara University, 34854, Istanbul, Turkiye.
Naturally occurring vitamin E is a lipophilic plant-derived molecule corresponding to the 2R forms of alpha-tocopherol. A series of natural analogs or tocochromanols are present in nature, including β-, γ- and δ-tocopherol (βT, γT, δT), the corresponding tocotrienols (αTE, βTE, γTE, δTE) and tocomonoenols. Differences between these analogs as lipophilic antioxidants and modulators of molecular processes suggest specific therapeutic properties against various disorders associated with acute and chronic inflammation.
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February 2025
Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA.
Cellular metabolism is inextricably linked to transmembrane levels of proton (H), sodium (Na), and potassium (K) ions. Although reduced sodium-potassium pump (Na-K ATPase) activity in tumors directly disturbs transmembrane Na and K levels, this dysfunction is a result of upregulated aerobic glycolysis generating excessive cytosolic H (and lactate) which are extruded to acidify the interstitial space. These oncogene-directed metabolic changes, affecting intracellular Na and H, can be further exacerbated by upregulation of ion exchangers/transporters.
View Article and Find Full Text PDFBiochemistry
January 2025
Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States.
1-Deoxy-d-xylulose 5-phosphate synthase (DXPS) is a unique thiamin diphosphate (ThDP)-dependent enzyme that catalyzes the formation of DXP, a branchpoint metabolite required for the biosynthesis of vitamins and isoprenoids in bacterial pathogens. DXPS has relaxed substrate specificity and utilizes a gated mechanism, equipping DXPS to sense and respond to diverse substrates. We speculate that pathogens utilize this distinct gated mechanism in different ways to support metabolic adaptation during infection.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Sports Medical Science, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Postoperative adhesion around nerves sometimes results in sensory and motor dysfunctions. To prevent these disorders, we have developed an electrospun nanofiber sheet incorporating methylcobalamin (MeCbl), an active form of vitamin B12 with anti-inflammatory and neuroregenerative effects. This study aimed to investigate the neuroprotective effects of MeCbl sheets against postoperative adhesion and to compare the effects of MeCbl sheets with those of porcine small intestinal submucosa (SIS) sheets using a rat sciatic nerve adhesion model.
View Article and Find Full Text PDFSAGE Open Med Case Rep
January 2025
Memorial University of Newfoundland, St. John's, NL, Canada.
Erosive pustular dermatosis is a rare and chronic inflammatory condition of the scalp which can be mistaken for cutaneous malignancy, precancerous lesions, dermatitis or pyoderma gangrenosum. The recurrent and resistant characteristics of erosive pustular dermatosis of the scalp pose a challenge to successful management and remission of the condition. The purpose of this case report is to provide management options and treatment recommendations for refractory cases of erosive pustular dermatosis of the scalp.
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