- Substituents Have a Large Effect on Photochemical Generation of Benzyl Cations and DNA Cross-Linking
-
Photoactivated DNA interstrand cross-linking agents have a wide range of biological applications. Recently, several aryl boronates have been reported to induce DNA interstrand cross-link (ICL) formation via carbocations upon photoirradiation. Herein, we synthesized a series of new bifunctional phenyl compounds to test the generality of such a mechanism, and to understand how the chemical structure influences carbocation formation and the DNA cross-linking process. These compounds efficiently form DNA ICLs via generated benzyl cations upon 350 nm irradiation. The DNA cross-linking efficiency and the pathway for carbocation generation depend on both the aromatic substituents and the leaving groups. Bromine as a leaving group facilitates the DNA cross-linking process in comparison with trimethyl ammonium salt. Both electron-donating and -withdrawing substituents induce bathochromic shifts, which favor photoinduced DNA ICL formation. For the bromides, the benzyl cation intermediates were generated through oxidation of the corresponding benzyl radicals. However, for the ammonia salts, the benzyl cations were formed through two pathways: either through oxidation of the benzyl radicals or by direct heterolysis of the C?N bond. Photoinduced C?N homolysis to form benzyl radicals occurred with compounds having donating substituents, whereas direct heterolysis of the C?N bond occurred with those bearing withdrawing substituents. The adducts formed between 1 a and four natural nucleosides were characterized, indicating that the alkylation sites for the photogenerated benzyl cations are dG, dA, and dC.
- Fan, Heli,Sun, Huabing,Peng, Xiaohua
-
p. 7671 - 7682
(2018/05/14)
-
- Highly Selective Carbon Dioxide Capture and Cooperative Catalysis of a Water-Stable Acylamide-Functionalized Metal–Organic Framework
-
Incorporation of specific functionalities within the framework offers a significant opportunity to produce high-performance gas storage/separation and catalysis MOF materials. In this work, multifunctionalities, including hydrophobic methoxy groups, polar acylamide functionalities, and open copper(II) sites, have been successfully integrated into a twofold interpenetrated microporous MOF (HNUST-6, HNUST represents Hunan University of Science and Technology). HNUST-6 possesses permanent porosity, with a moderate BET surface area of 1093 m2 g–1 and high CO2 adsorption capacity (111 cm3 g–1 at 1 bar), with good selectivity for CO2 over CH4 (6.6) and N2 (30.3) at 273 K. Remarkably, this MOF material exhibits excellent water stability and its framework structure is retained after being immersed in boiling water. In addition, HNUST-6 demonstrates efficient catalytic activity as a cooperative catalyst in a tandem one-pot deacetalization Knoevenagel condensation reaction.
- Wang, Zhaoxu,Luo, Xin,Zheng, Baishu,Huang, Lu,Hang, Cheng,Jiao, Yinchun,Cao, Xiyang,Zeng, Wenjiang,Yun, Ruirui
-
p. 1309 - 1314
(2018/04/02)
-
- Self-Exfoliated Metal-Organic Nanosheets through Hydrolytic Unfolding of Metal-Organic Polyhedra
-
Few-layers thick metal-organic nanosheets have been synthesized using water-assisted solid-state transformation through a combined top-down and bottom-up approach. The metal-organic polyhedra (MOPs) convert into metal-organic frameworks (MOFs) which subse
- Garai, Bikash,Mallick, Arijit,Das, Anuja,Mukherjee, Rabibrata,Banerjee, Rahul
-
supporting information
p. 7361 - 7366
(2017/05/31)
-
- Coordination polymers of 5-substituted isophthalic acid
-
The synthesis and characterisation of five coordination polymers - Ni2(mip)2(H2O)8·2H2O (1), Zn6(mip)5(OH)2(H2O)4·7.4H2O (2), Zn6
- McCormick, Laura J.,Morris, Samuel A.,Slawin, Alexandra M. Z.,Teat, Simon J.,Morris, Russell E.
-
p. 1123 - 1132
(2016/02/18)
-
- Coordination polymers of ZnII and 5-methoxy isophthalate
-
Solvothermal reaction of Zn(OAc)2 and 5-methoxy isophthalic acid (H2MeOip) in aqueous alcohols ROH (R = H, Me, Et, or iPr) affords four different novel coordination polymers. Zn2(HMeOip)(MeOip)(OAc) (1) forms as a 1D 'ribbon of rings' polymer. Zn6(MeOip)4.5(HMeOip)(OH)2(H2O)2·5.5H2O (2) crystallises as a complex 3D framework. Zn(MeOip)(H2O)2 H2O (3) is a 1D coordination polymer that contains almost planar strips of Zn(MeOip). compound 4, Zn5(MeOip)4(OH)2(H2O)4·H2O, obtained from aqueous iPrOH, crystallises as a 2D polymer containing two crystallographically distinct Zn5(OH)2 clusters. Preliminary nitric oxide release experiments have been conducted.
- McCormick, Laura J.,Morris, Samuel A.,Teat, Simon J.,McPherson, Matthew J.,Slawin, Alexandra M. Z.,Morris, Russell E.
-
p. 17686 - 17695
(2015/10/19)
-
- Bispyrrolylbenzene anion receptor: From supramolecular switch to molecular logic gate
-
We have designed anion receptor 4 based on a conformationally labile bispyrrolylbenzene framework, the conformation of which can be changed by appropriate anionic stimuli. In the absence of fluoride anion, the pyrrole moieties rotate freely at room temperature. However, when the concentration of fluoride anion exceeds 2 equivalents, the rotation of the pyrrole units slows down and the conformation of the receptor changes to anti-anti. DFT calculations have shown that this change is due to binding of a third fluoride anion through C-H interaction. Anion receptor 4 can also serve as a molecular logic gate. Anionic inputs such as fluoride and dihydrogenphosphate allow the realization of INHIBIT and NAND logic gate functions with absorption and fluorescence as readouts, respectively.
- Granda, Jaroslaw M.,Staszewska-Krajewska, Olga,Jurczak, Janusz
-
supporting information
p. 12790 - 12795
(2015/03/30)
-
- Birch Reductive Alkylation of Methyl m-(Hydroxymethyl)benzoate Derivatives and the Behavior of o- and p-(Hydroxymethyl)benzoates under Reductive Alkylation Conditions
-
Birch reductive alkylation of methyl m-(hydroxymethyl)benzoate derivatives, using lithium in ammonia-tetrahydrofuran in the presence of tertbutyl alcohol, can be achieved without significant loss of benzylic oxygen substituents. Similar treatment of o- and p-(hydroxymethyl)benzoate derivatives results largely in loss of benzylic oxygen substituents. The results are rationalized by computations describing electron density patterns in the putative radical anion intermediate involved in these reactions.
- Fretz, Samuel J.,Hadad, Christopher M.,Hart, David J.,Vyas, Shubham,Yang, Dexi
-
-
- Polycyanurate networks with enhanced segmental flexibility and outstanding thermochemical stability
-
The synthesis and physical properties of cyanurate networks formed from two new tricyanate monomers, 1,3,5-tris[(4-cyanatophenylmethyl]benzene and 3,5-bis[(4-cyanatophenylmethyl)]phenylcyanate, are reported and compared to those of 1,1,1-tris[(4-cyanatoph
- Guenthner, Andrew J.,Davis, Matthew C.,Ford, Michael D.,Reams, Josiah T.,Groshens, Thomas J.,Baldwin, Lawrence C.,Lubin, Lisa M.,Mabry, Joseph M.
-
p. 9707 - 9718
(2013/03/13)
-
- DABCO-directed self-assembly of bisporphyrins (DABCO = 1,4-diazabicyclo[2. 2.2]octane)
-
Three isomeric zinc bisporphyrins have been prepared by covalently linking together two aminoporphyrins with an isophthalic acid derivative. The porphyrins differ in the substitution pattern on the meso phenyl groups, that is, ortho, meta, or para. Titrations carried out by UV-visible and 1H NMR spectroscopy have been used to map out the stabilities and the stoichiometries of the complexes formed with 1,4-diazabicyclo[2.2.2]octane (DABCO) in chloroform. The ortho-and meta-substituted bisporphyrins form 1:1 intramolecular sandwich complexes. The para-substituted bisporphyrin cannot adopt the cofacial conformation required for this type of complex and forms a higher order 2:2 intermolecular assembly, which is stable over a wide range of DABCO concentrations.
- Ballester, Pablo,Costa, Antoni,Castilla, Ana M.,Deya, Pere M.,Frontera, Antonio,Gomila, Rosa M.,Hunter, Christopher A.
-
p. 2196 - 2206
(2007/10/03)
-
- Heteropolycyclic compounds and their use as metabotropic glutamate receptor antagonists
-
The present invention provides compounds and pharmaceutical compositions that act as antagonists at metabotropic glutamate receptors, and that are useful for treating neurological diseases and disorders. Methods of preparing the compounds also are disclosed.
- -
-
-
- Aromatic analogs of arcaine inhibit MK-801 binding to the NMDA receptor
-
Aromatic analogs of arcaine were shown to have inhibitory effects on the binding of the channel blocking drug [3H]MK-801 to the NMDA receptor complex. The most potent compound of the series was an N,N - bis(propyl)guanidinium which inhibited [3H]MK-801 binding with an IC50 of 0.58 μM and an IC50 of 12.17 μM upon addition of 100 μM spermidine. The increase in IC50 upon addition of spermidine suggests competitive antagonism between the inhibitor and spermidine at the arcaine-sensitive polyamine site of the NMDA receptor complex.
- Sharma, Terre A.,Carr, Andrew J.,Davis, Rebecca S.,Reynolds, Ian J.,Hamilton, Andrew D.
-
p. 3459 - 3464
(2007/10/03)
-
- A new water-soluble bowl-shaped host by metal-induced self-assembly
-
A water-soluble bowl-shaped host, M3M, which possesses a hydrophobic binding cavity for apolar guests was prepared by metal-induced self-assembly through complexation of L-serine derived hydroxy acid groups with metals. Compound S without a xylenic linker
- Lee, Sang Bok,Hong, Jong-In
-
p. 4317 - 4320
(2007/10/03)
-
- 2-Methoxy-4,6-bis(trifluoromethyl)phenyllithium: A new stable aryllithium useful as an intermediate to bis(trifluoromethyl)aromatics
-
A method for the preparation of 3,5-bis(trifluoromethyl)anisole (3) has been developed. Lithiation of 3 occurred exclusively at the position ortho to the CH3O group to give a thermally stable lithium derivative 6 which readily undergoes conventional reactions with a number of electrophiles. Formylation and carboxylation of 6 gave bis(trifluoromethyl) derivatives of salicylic aldehyde and salicylic acid 9-12 in good yields.
- Dmowski, Wojciech,Piasecka-Maciejewska, Krystyna
-
-
- An Efficient and Practical Synthesis of Bicyclononane-2,4-diones
-
Cyclohexane-1,3-dicarboxylic anhydrides (IVa-c), prepared from isophthalic acids in several steps, were treated with diethyl magnesiomalonate and triethylamine to give 3-di(ethoxycarbonyl)acetylcyclohexanecarboxylic acids (Va-c) in good yields.Compounds V
- Yamazaki, Takao,Matoba, Katsuhide,Itooka, Toshiyuki,Chintani, Masaru,Momose, Takefumi,Muraoka, Osamu
-
p. 3453 - 3459
(2007/10/02)
-