20357-25-9Relevant articles and documents
Highly Efficient Supramolecular Catalysis by Endowing the Reaction Intermediate with Adaptive Reactivity
Jiao, Yang,Tang, Bohan,Zhang, Yucheng,Xu, Jiang-Fei,Wang, Zhiqiang,Zhang, Xi
, p. 6077 - 6081 (2018)
A new strategy of highly efficient supramolecular catalysis is developed by endowing the reaction intermediate with adaptive reactivity. The supramolecular catalyst, prepared by host–guest complexation between 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO) and cucurbit[7]uril (CB[7]), was used for biphasic oxidation of alcohols. Cationic TEMPO+, the key intermediate, was stabilized by the electrostatic effect of CB[7] in aqueous phase, thus promoting the formation of TEMPO+ and inhibiting side reactions. Moreover, through the migration into the organic phase, TEMPO+ was separated from CB[7] and recovered the high reactivity to drive a fast oxidation of substrates. The adaptive reactivity of TEMPO+ induced an integral optimization of the catalytic cycle and greatly improved the conversion of the reaction. This work highlights the unique advantages of dynamic noncovalent interactions on modulating the activity of reaction intermediates, which may open new horizons for supramolecular catalysis.
Polymer-supported IBX-amide reagents: Significant role of spacer and additive in alcohol oxidation
Chung, Woo-Jae,Kim, Duk-Ki,Lee, Yoon-Sik
, p. 2175 - 2178 (2005)
We found that the spacer and additive play a significant role in the oxidation of alkyl alcohols using polymer-supported IBX-amide reagents. The introduction of the spacer between the polymer support and IBX-amide group improved the initial conversion rate (up to 60% conversion). Furthermore, various alcohol compounds, when reacted with IBX-amide resin in the presence of BF3·OEt2, were effectively converted into the corresponding aldehydes or ketones within 5-30 minutes in high purities (>94%) at room temperature. Georg Thieme Verlag Stuttgart.
Non-alkylator anti-glioblastoma agents induced cell cycle G2/M arrest and apoptosis: Design, in silico physicochemical and SAR studies of 2-aminoquinoline-3-carboxamides
Gu, Xiangyu,Liu, Jianwen,Ni, Xintong,Qi, Yingxue,Qian, Xuhong,Shao, Xusheng,Xu, Xiaoyong,Yuan, Pengtao
supporting information, (2021/09/22)
Malignant gliomas are the most common brain tumors, with generally dismal prognosis, early clinical deterioration and high mortality. Recently, 2-aminoquinoline scaffold derivatives have shown pronounced activity in central nervous system disorders. We herein reported a series of 2-aminoquinoline-3-carboxamides as novel non-alkylator anti-glioblastoma agents. The synthesized compounds showed comparable activity to cisplatin against glioblastoma cell line U87 MG in vitro. Among them, we found that 6a displayed good inhibitory activity against A172 and U118 MG glioblastoma cell lines and induced cell cycle arrest in the G2/M phase and apoptosis in U87 MG by flow cytometry analysis. Additionally, 6a displayed low cytotoxicity to several normal human cell lines. In silico study showed 6a had promising physicochemical properties and was predicted to cross the blood–brain barrier. Moreover, preliminary structure–activity relationships are also investigated, shedding light on further modifications towards more potent agents on this series of compounds. Our results suggest this compound has a promising potential as an anti-glioblastoma agent with a differential effect between tumor and non-malignant cells.
Synthesis and photochemical studies of 2-nitrobenzyl-caged N-hydroxysulfonamides
Zhou, Yang,Bharadwaj, Vinay,Rahman, Mohammad S.,Sampson, Paul,Brasch, Nicola E.,Seed, Alexander J.
, (2019/09/09)
Recently, N-hydroxysulfonamides (RSO2NHOH) caged by photolabile protecting groups have attracted significant interest as potential photoactive nitroxyl (HNO) donors. The selectivity of the desired HNO generation pathway from photocaged N-hydroxysulfonamides versus a competing pathway involving O-N bond cleavage is dependent on the specific photodeprotection mechanism of the phototrigger. We present a new class of photocaged N-hydroxysulfonamides incorporating the well-established o-nitrobenzyl photoprotecting group, including a derivative incorporating an additional carbonate linker. Photodecomposition of o-NO2Bn-ON(H)SO2CF3 and the corresponding 2-nitro-4,5-dimethoxybenzyl analog generated the desired HNO and CF3SO2- as a minor pathway, with competing photoinduced O-N bond cleavage to release CF3SO2NH2 as the major photodecomposition pathway. Photolysis of the corresponding -SO2CH3 analogs resulted in O-N bond cleavage only. The presence of the o-nitro substituent was shown to be essential for photoactivity. Photorelease of the parent HNO donor CH3SO2NHOH was observed as the major product upon irradiation of o-NO2Bn-OC(O)ON(H)SO2CH3, with the desired HNO release and O-N bond cleavage occurring as minor pathways. Photoproduct quantum yields for each species have been determined by actinometry. The effect of solvent, pH and air on the mechanism of photodecomposition was studied for o-NO2Bn-ON(H)SO2CH3. The ratio of the solvents in the solvent mixture (CH3CN and phosphate buffer, pH 7.0), the pH of the aqueous component of the buffer, and the presence of oxygen did not affect the amount of each photoproduct and the observed rate constant for O-N bond cleavage. Possible mechanisms for the various pathways are proposed.