نتایج جستجو برای: hydroxy groups protection
تعداد نتایج: 924287 فیلتر نتایج به سال:
The ability to specifically engineer metal binding sites into target proteins has far-reaching consequences ranging from the development of new biocatalysts and imaging reagents to the production of proteins with increased stability. We report the efficient tRNA-mediated incorporation of the hydroxamate containing amino acid, N(ε)-acetyl-N(ε)-hydroxy-L-lysine, into a transcription factor (TFIII...
Here, we describe the chemical synthesis of the complete sets of 18 novel 3- and 21-monosulfates and their double-conjugated form of tetrahydrocortisol (THF), tetrahydro-11-deoxycortisol (THS), and tetrahydrocortisone (THE) in the 5alpha- and 5beta-series. The principal reactions involved are: (1) selective protection of a specific hydroxy group in substrates; (2) catalytic hydrogenation at C-5...
OBJECTIVES Non-alcoholic steatohepatitis (NASH), is an important component of Non-alcoholic fatty liver disease (NAFLD) spectrum, which progresses to the end stage liver disease, if not diagnosed and treated properly. The disproportionate production of pro- and anti-inflammatory adipokines secreted from fat contributes to the pathogenesis of NASH. In this study, the comparative effect of piogli...
The review describes chemical transformations of multifunctional compounds (amino acids and peptides, amino alcohols, amino thiols, hydroxy acids, oxo acids, oxo alcohols, compounds containing simultaneously three or more different groups etc.) by using step-wise or one-step modification or protection of functional groups. Some chemical aspects of mixed derivatization performed for improving th...
Chemical investigation of the methanol crude extract dried flower buds Syzygium aromaticum (Myrtaceae) resulted in isolation seven known compounds; oleanolic acid (1), lignoceric (2), β-sitosterol (3), heneicosanoic (4), 5-hydroxy-7-methoxy-2-methylchromone (5), 5-hydroxy-7-methoxy-2,8-dimethylchromone (6) and vanillin (7). Their structures were elucidated using one-dimensional NMR spectroscopy...
The preparation of cyclic 10-membered tetrahydroxy enediynes is reported. The synthesis starts from tartaric acid and allows the control of the relative stereochemistry. Acetal protection of the 2,3-hydroxy groups stabilizes the enediyne during synthesis. Removal of the cyclic protecting group with EtSH/TFA transforms the stable compounds into reactive enediynes, and the rate constants of their...
We completed a new and efficient synthesis of D-chalcose (I) and the first synthesis of its C-3 epimer (I') in nine steps with overall yields of 23% and 24%, respectively. The key steps in the sequence were the formation of the stereocenter on C3 via Grignard reaction, the introduction of the stereogenic center on C2 by Sharpless asymmetric dihydroxylation, the protection of the C1 and C2 hydro...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید