The carbohydrate subunits carrying an N-O-interglycosidic bond play a very important role in the biological activity of the enediyne antibiotics. Condensation of O-(alpha- and beta-D-glucopyranosyl)hydroxylamine (5a and 5b) with the hex-3-ulopyranoside (6) furnished methyl 4,6-O-benzylidene-2,3-dideoxy-3-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyloxy)imino-alpha- and beta-D-erythro-hexopyranoside (7a and 7b). Stereoselective reduction of the Cz.dbnd6;N bond of 7a and 7b with sodium cyanoborohydride resulted in the formation of the required protected N-O-interglycosidic disaccharides (8a and 8b). Finally, catalytic hydrogenation of 8a afforded methyl 2,3-dideoxy-3-(alpha-D-glucopyranosyloxy)amino-alpha-D-ribo-hexopyranoside (9a). Under similar conditions the beta anomer 8b underwent decomposition.
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http://dx.doi.org/10.1016/s0008-6215(03)00270-2 | DOI Listing |
Plant Cell Rep
January 2025
State Key Laboratory of Crop Genetics and Germplasm Enhancement, Saya Institute of Nanjing Agricultural University, Nanjing Agricultural University, Nanjing, 211800, China.
This study indicated that the CCHC-type zinc finger protein PbrZFP719 involves into self-incompatibility by affecting the levels of reactive oxygen species and cellulose content at the tips of pollen tubes. S-RNase-based self-incompatibility (SI) facilitates cross-pollination and prevents self-pollination, which in turn increases the costs associated with artificial pollination in fruit crops. Self S-RNase exerts its inhibitory effects on pollen tube growth by altering cell structures and components, including reactive oxygen species (ROS) level and cellulose content.
View Article and Find Full Text PDFCancer Biol Ther
December 2025
Department of Pharmacology, Physiology, and Cancer Biology, Thomas Jefferson University, Philadelphia, PA, USA.
Adaptive immune resistance in cancer describes the various mechanisms by which tumors adapt to evade anti-tumor immune responses. IFN-γ induction of programmed death-ligand 1 (PD-L1) was the first defined and validated adaptive immune resistance mechanism. The endoplasmic reticulum (ER) is central to adaptive immune resistance as immune modulatory secreted and integral membrane proteins are dependent on ER.
View Article and Find Full Text PDFMol Ther
January 2025
Department of Orthopaedic surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. Electronic address:
Tumor necrosis factor receptor-associated factor 1 (TRAF1) is a crucial signaling adaptor involved in multiple cellular events. However, its role in regulating osteoclastogenesis and energy metabolism remains unclear. Here, we report that TRAF1 promotes osteoclastogenesis and oxidative phosphorylation (OXPHOS).
View Article and Find Full Text PDFLipids Health Dis
January 2025
Department of Neurosurgery, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu, 213000, China.
Background: Stroke has emerged as an escalating public health challenge among middle-aged and older individuals in China, closely linked to glycolipid metabolic abnormalities. The Hemoglobin A1c/High-Density Lipoprotein Cholesterol (HbA1c/HDL-C) ratio, an integrated marker of glycolipid homeostasis, may serve as a novel predictor of stroke risk.
Methods: Our investigation utilized data from the China Health and Retirement Longitudinal Study cohort (2011-2018).
Cell Commun Signal
January 2025
Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, 100191, China.
Background: Ovarian cancer (OC), particularly high-grade serous ovarian carcinoma (HGSOC), is the leading cause of mortality from gynecological malignancies worldwide. Despite the initial effectiveness of treatment, acquired resistance to poly(ADP-ribose) polymerase inhibitors (PARPis) represents a major challenge for the clinical management of HGSOC, highlighting the necessity for the development of novel therapeutic strategies. This study investigated the role of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a pivotal regulator of glycolysis, in PARPi resistance and explored its potential as a therapeutic target to overcome PARPi resistance.
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