705-15-7Relevant articles and documents
Kinetic ( 18 O and 14 C) and Magnetic ( 13 C) Isotope Effects in the Photo-Fries Rearrangement of 4-Methoxyphenyl Acetate
Shine, Henry J.,Subotkowski, Witold
, p. 3815 - 3821 (1987)
Kinetic isotope effects (KIE) were measured for the photorearrangement of 4-methoxyphenyl acetate (1) into 2-acetyl-4-methoxyphenol (2) in ethanol solution.The KIE for labeling the phenolic oxygen atom with 18 O was 1.0000+/-0.0023.The KIE for labeling with 14 C at the α-carbon atom of the acetyl group was measured in two ways: with recovered 1 (0.9988+/-0.0051) and with isolated 2 (1.007+/-0.008).Labeling with 13 C at the α-carbon atom led to a magnetic, inverse isotope effect (0.9511+/-0.0042).The results show that there is not a detectable activation barrier for breaking the ester bond and that 2 is formed by recombination of a caged radical pair which originates from an excited singlet state.Surprisingly, labeling of 1 with 14 C in the ortho position led to a KIE, measured with recovered 1, of 1.0286+/-0.0021.We attribute this to a reaction of 1, as yet unknown, which is not associated with rearrangement into 2.It is noteworthy that rearrangement is not the major reaction pathway.The larger part (over 60percent) of 1 is converted into polymeric material.The origin of the polymeric material lay in the scission product, 4-methoxyphenol (3), which was itself not obtained during the lengthy irradiations of the KIE work.Whether the KIE for ortho labeling is connected with polymer formation is not now known.
Anchimerically Assisted Selective Cleavage of Acid-Labile Aryl Alkyl Ethers by Aluminum Triiodide and N, N-Dimethylformamide Dimethyl Acetal
Sang, Dayong,Yue, Huaxin,Zhao, Zhengdong,Yang, Pengtao,Tian, Juan
, p. 6429 - 6440 (2020/07/14)
Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.
Design, synthesis and docking study of pyridine and thieno[2,3-b] pyridine derivatives as anticancer PIM-1 kinase inhibitors
Abdelaziz, Marwa E.,El-Miligy, Mostafa M.M.,Fahmy, Salwa M.,Mahran, Mona A.,Hazzaa, Aly A.
, p. 674 - 692 (2018/08/02)
A series of pyridine and thieno[2,3-b]pyridine derivatives have been designed and synthesized as anticancer PIM-1 kinase inhibitors. Thirty-seven compounds were selected by NCI to be tested initially at a single dose (10 μM) in the full NCI 60 cell line panel. Compound 5b showed potent anticancer activity and was tested twice in the five-dose assay which confirmed its potent antitumor activity (GI50 values 0.302–3.57 μM) against all tested tumor cell lines except six cell lines where they showed moderate sensitivity. This compound was sent to NCI biological evaluation committee and still under consideration for further testing. In addition, the most active anticancer compounds in each series, 5b, 8d, 10c, 13h, and 15e, were evaluated for their PIM-1 kinase inhibitory activity. Compound 8d was the most potent one with IC50 = 0.019 μM followed by 5b, 15e, 10c and 13h with IC50 values 0.044, 0.083, 0.128 and 0.479 μM respectively. Moreover, docking study of the most active compounds in PIM-1 kinase active site was consistent with the in vitro activity.