1023-94-5Relevant academic research and scientific papers
Grignard reagents: Alkoxide-directed iodine-magnesium exchange at sp 3 centers
Fleming, Fraser F.,Gudipati, Subrahmanyam,Vu, Viet Anh,Mycka, Robert J.,Knochel, Paul
, p. 4507 - 4509 (2007)
(Chemical Equation Presented) Sequential addition of i-PrMgCl and BuLi to sp3 hybridized iodoalcohols triggers a facile iodine-metal exchange. Intercepting the resulting cyclic Grignard reagents with a slight excess of an electrophile leads to a diverse range of substituted alcohols. The iodine-magnesium exchange strategy is effective with 3-carbon iodoalcohols bearing alkyl substitutents on the carbinol or adjacent carbons and with the chain-extended homolog 4-iodobutan-1-ol.
Fluspirilene Analogs Activate the 20S Proteasome and Overcome Proteasome Impairment by Intrinsically Disordered Protein Oligomers
Fiolek, Taylor J.,Keel, Katarina L.,Tepe, Jetze J.
, p. 1438 - 1448 (2021/05/04)
Oligomerization of aggregation-prone intrinsically disordered proteins (IDPs), such as α-synuclein, amyloid β, and tau, has been shown to be associated with the pathogenesis of several neurodegenerative diseases, including Parkinson's and Alzheimer's disease. The proteasome is charged with regulating cellular levels of IDPs, but this degradation pathway can become dysregulated leading to their accumulation and subsequent aggregation. Although the pathogenesis of these neurodegenerative diseases is still under intense investigation, it has been shown that the oligomeric forms of IDPs, including α-synuclein and amyloid β, can impair proteasome function. This leads to additional accumulation of the IDPs, further promoting disease progression. Herein, we report the use of small molecule activators of the 20S subcomplex of the proteasome to restore impaired 20S proteasome activity and prevent IDP accumulation and oligomerization. We found that fluspirilene and its new synthetic analog (16) show strong 20S proteasome enhancement (doubling 20S proteolytic activity at μ2 μM, with maximum fold enhancement of μ1000%), overcome impaired proteasome function, and prevent the accumulation of pathogenic IDPs. These findings provide support for the use of 20S enhancers as a possible therapeutic strategy to combat neurodegenerative diseases.
DMSO-Enabled Selective Radical O?H Activation of 1,3(4)-Diols
Han, Bing,Jiao, Ning,Jin, Rui,Liu, Guoquan,Liu, Jianzhong,Zhang, Ziyao,Zhu, Yuchao
supporting information, p. 19851 - 19856 (2020/09/04)
Control of selectivity is one of the central topics in organic chemistry. Although unprecedented alkoxyl-radical-induced transformations have drawn a lot of attention, compared to selective C?H activation, selective radical O?H activation remains less explored. Herein, we report a novel selective radical O?H activation strategy of diols by combining spatial effects with proton-coupled electron transfer (PCET). It was found that DMSO is an essential reagent that enables the regioselective transformation of diols. Mechanistic studies indicated the existence of the alkoxyl radical and the selective interaction between DMSO and hydroxyl groups. Moreover, the distal C?C cleavage was realized by this selective alkoxyl-radical-initiation protocol.
Heterocyclization involving benzylic C(sp3)-H functionalization enabled by visible light photoredox catalysis
Pandey, Ganesh,Laha, Ramkrishna,Mondal, Pradip Kumar
, p. 9689 - 9692 (2019/08/15)
A general and efficient method for heterocyclization involving benzylic C(sp3)-H functionalization enabled by visible light photoredox catalysis to access a wide range of structurally diverse oxygen as well as nitrogen heterocycles up to a gram scale is reported. The potential application of this new methodology is demonstrated by the total synthesis of (-)-codonopsinine and (+)-centrolobine. Herein it is proposed that selectfluor, unlike a fluorinating reagent, acts as an oxidative quencher and a hydrogen radical acceptor.
Analogs of penfluridol as chemotherapeutic agents with reduced central nervous system activity
Ashraf-Uz-Zaman, Md,Sajib, Md Sanaullah,Cucullo, Luca,Mikelis, Constantinos M.,German, Nadezhda A.
supporting information, p. 3652 - 3657 (2018/11/03)
Several recent reports have highlighted the feasibility of the use of penfluridol, a well-known antipsychotic agent, as a chemotherapeutic agent. In vivo experiments have confirmed the cytotoxic activity of penfluridol in triple-negative breast cancer model, lung cancer model, and further studies have been proposed to assess its anticancer activity and viability for the treatment of glioblastomas. However, penfluridol anticancer activity was observed at a dosage significantly higher than that administered in antipsychotic therapy, thus raising the concern for the potential onset of CNS side effects in patients undergoing intensive pharmacological treatment. In this study, we evaluate the potential CNS toxicity of penfluridol side by side with a set of analogs.
Copper-catalyzed aerobic C-C bond cleavage of lactols with N-hydroxy phthalimide for synthesis of lactones
Tnay, Ya Lin,Chiba, Shunsuke
supporting information, p. 873 - 877 (2015/04/14)
The transformation of cyclic hemiacetals (lactols) into lactones has been achieved by Cu-catalyzed aerobic C-C bond cleavage in the presence of N-hydroxy phthalimide (NHPI). The present process is composed of a multistep sequence including a) formation of exo-cyclic enol ethers by dehydration; b) addition of phthalimide N-oxyl radical to the enol ethers followed by trapping of the resulting C-radicals with molecular oxygen to form peroxy radicals; c) reductive generation of oxy radicals and subsequent β-radical fragmentation to generate lactones.
Concise, stereodivergent and highly stereoselective synthesis of cis-and trans-2-substituted 3-hydroxypiperidines-development of a phosphite-driven cyclodehydration
Huy, Peter H.,Westphal, Julia C.,Koskinen, Ari M.P.
supporting information, p. 369 - 383 (2014/03/21)
A concise (5 to 6 steps), stereodivergent, highly diastereoselective (dr up to >19:1 for both stereoisomers) and scalable synthesis (up to 14 g) of cis- and trans-2-substituted 3-piperidinols, a core motif in numerous bioactive compounds, is presented. This sequence allowed an efficient synthesis of the NK-1 inhibitor L-733,060 in 8 steps. Additionally, a cyclodehydration-realizing simple triethylphosphite as a substitute for triphenylphosphine is developed. Here the stoichiometric oxidized P(V)-byproduct (triethylphosphate) is easily removed during the work up through saponification overcoming separation difficulties usually associated to triphenylphosphine oxide.
Efficient, stereodivergent access to 3-piperidinols by traceless P(OEt)3 cyclodehydration
Huy, Peter H.,Koskinen, Ari M. P.
supporting information, p. 5178 - 5181 (2013/11/06)
A stereodivergent and highly diastereoselective (dr up to >19:1 for both isomers), step economic (5-6 steps), and scalable synthesis (up to 14 g) of cis- and trans-2-substituted 3-piperidinols, the core motif of numerous bioactive compounds, providing efficient access to the NK-1 inhibitor L-733,060 is presented. Additionally, a "traceless" (referring to the simplified byproduct separation) cyclodehydration realizing simple P(OEt)3 as a substitute for PPh3 is developed.
Chiral phosphoric acid-catalyzed enantioselective and diastereoselective spiroketalizations
Sun, Zhankui,Winschel, Grace A.,Borovika, Alina,Nagorny, Pavel
supporting information; experimental part, p. 8074 - 8077 (2012/07/14)
Catalytic enantioselective and diastereoselective spiroketalizations with BINOL-derived chiral phosphoric acids are reported. The chiral catalyst can override the inherent preference for the formation of thermodynamic spiroketals, and highly selective formation of nonthermodynamic spiroketals could be achieved under the reaction conditions.
Synthesis and SAR study of diphenylbutylpiperidines as cell autophagy inducers
Chen, Gang,Xia, Hongguang,Cai, Yu,Ma, Dawei,Yuan, Junying,Yuan, Chengye
scheme or table, p. 234 - 239 (2011/02/26)
A novel series of diphenylbutylpiperidines as autophagy inducers was described and extensive SAR studies resulted in derivatives (15d-e, 15i-j) with 10-fold greater activity than the lead compounds 1 and 2. Meanwhile, a new synthetic route to diphenylbutyl bromide (6) from bromobenzene and γ-butyrolactone was also reported here.
