- Cyclopropylidenemethanone: A Quasi-Symmetrical Molecule
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The structure of cyclopropylidenemethanone has been investigated via microwave spectroscopy.Analysis of the spectra of the ground and nine excited vibrational states has revealed the form of two bending potentials involving motion of the methanone group relative to the cyclopropylidene ring.The vibration perpendicular to the plane containing the ring carbon atoms has a double-minimum potential with the ground state lying just 2 cm-1 below the 29 cm-1 high central barrier.Analysis of this motion using the rigid bender method shows that the two potential minima lie 17.5 deg away from the ring plane.The proximity of the ground state to the top of the barrier leads to the designation of the molecule as quasi-symmetric, being close to C2ν, despite its less symmetric Cs equilibrium structure.The vibration in the plane of the ring has a near harmonic potential, with a fundamental of 154 cm-1.Analysis of the Stark effect indicates a dipole moment of 2.60(1) D.
- Brown, Ronald D.,Godfrey, Peter D.,Kleiboemer, Burkhard,Champion, Robert,Elmes, Patricia S.
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- Preparation method and application of compound containing zinc-bound and quinoline skeleton
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The invention relates to the field of pharmaceutical chemistry, in particular to a novel zinc-containing binding group-containing quinoline compound. A geometric isomer, a pharmaceutically acceptable salt, solvate or prodrug thereof, a preparation method and thereof, and a pharmaceutical composition containing the compound. The invention also relates to an application of the compound in preparation of drugs for treating and/or preventing diseases mediated by c-Met tyrosine kinase and HDAC. The quinoline compounds, geometric isomers and pharmaceutically acceptable salts, solvates and prodrugs thereof are shown in the specification, and R. 1 , m, Q, X, As described in the claims and the description.
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Paragraph 0139-0142
(2021/11/10)
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- Inherent Reactivity of Spiro-Activated Electrophilic Cyclopropanes
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The kinetics of the ring-opening reactions of thiophenolates with geminal bis(acceptor)-substituted cyclopropanes in DMSO at 20 °C was monitored by photometric methods. The determined second-order rate constants of the SN2 reactions followed linear relationships with Mayr nucleophilicity parameters (N/sN) and Br?nsted basicities (pKaH) of the thiophenolates as well as with Hammett substituent parameters (σ) for groups attached to the thiophenolates. Phenyl-substituted cyclopropanes reacted by up to a factor of 15 faster than their unsubstituted analogues, in accord with the known activating effect of adjacent π-systems in SN2 reactions. Variation of the electronic properties of substituents at the phenyl groups of the cyclopropanes gave rise to parabolic Hammett relationships. Thus, the inherent SN2 reactivity of electrophilic cyclopropanes is activated by electron-rich π-systems because of the more advanced C1?C2 bond polarization in the transition state. On the other hand, electron-poor π-systems also lower the energetic barriers for the attack of anionic nucleophiles owing to attractive electrostatic interactions.
- Jüstel, Patrick M.,Ofial, Armin R.,Pignot, Cedric D.,Stan, Alexandra
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supporting information
p. 15928 - 15935
(2021/10/25)
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- Discovery of novel dual c-Met/HDAC inhibitors as a promising strategy for cancer therapy
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Owing to the low efficacy and acquired resistance in clinical trials of c-Met inhibitors, based on the synergistic effects between c-Met and HDAC, novel c-Met and HDAC dual inhibitors were designed and synthesized. We introduced 2-pyrrolidinone to form the 5-atoms linker for c-Met inhibitor and hydroxamic acid as a zinc binding motif for HDAC inhibitor. The highly active dual inhibitor 15f showed excellent and balanced activity against both c-Met (IC50 = 12.50 nM) and HDAC1 (IC50 = 26.97 nM). In those tested tumor cell lines, 15f exhibits efficient antiproliferative activity with greater potency than Vorinostat (SAHA) and Cabozantinib (XL184). However, by comparing with an equimolar mixture of SAHA and Foretinib, we did not observe the compounds showed clearly synergistic antiproliferative effect. Nevertheless, compound 15f was found to induce apoptosis and cause cell cycle arrest in G2/M phase. This proof-of-concept study provides an efficient strategy for discovery of multitarget antitumor drugs.
- Chen, Fei,Dong, Yuhong,Gong, Ping,Hu, Hao,Liu, Yajing
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- An efficient method for the synthesis of 2′,3′-nonsubstituted cycloalkane-1,3-dione-2-spirocyclopropanes using (2-bromoethyl)-diphenylsulfonium trifluoromethanesulfonate
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An efficient and practical synthesis of 2′,3′-nonsubstituted cyclohexane-1,3-dione-2-spirocyclopropanes using a sulfonium salt was achieved. The reaction of 1,3-cyclohexanediones and (2-bromoethyl)diphenylsulfonium trifluoromethanesulfonate with powdered K2CO3 in EtOAc at room temperature (r.t.) provided the corresponding spirocyclopropanes in high yields. The synthetic method was also applied to 1,3-cyclopentanedione, 1,3-cycloheptanedione, 1,3-indanedione, acyclic 1,3-diones, ethyl acetoacetate, and Meldrum's acid.
- Nambu, Hisanori,Ono, Naoki,Hirota, Wataru,Fukumoto, Masahiro,Yakura, Takayuki
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p. 1763 - 1768
(2016/12/09)
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- Synthesis of 5-(2-chloroalkyl)-2,2-dimethyl-1,3-dioxane-4,6-diones
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A method has been worked out to synthetize hitherto unknown 5-(2-chloroalkyl) Meldrum's acids 4 starting from easily accessible 2-chlorocarboxylic acid chlorides 1 in a two-step reaction. Reactions of dihaloethane and Meldrum's acid in the presence of potassium carbonate and the usefulness of compounds 4 are also presented.
- Toth, Gyoergy,Tamas, Tivadar,Borbely, Ildiko
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p. 3659 - 3665
(2007/10/03)
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- A novel synthesis of 1-aminocyclopropane-1-carboxylic acid (ACC)
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A novel synthetic route of 1-aminocyclopropane-1-carboxylic acid (ACC) has been built via cyclopropanedicarboxylic acid monohydrazide II in moderation to good yield.
- Zhu, Xuxiang,Gan, Ping
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p. 3159 - 3162
(2007/10/03)
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