- Molecular recognition in ternary complexes of γ-cyclodextrin with naphthalenedicarboxylate ions and a space-regulator ion
-
Complexation of γ-cyclodextrin (γ-CD) with the 2,6- naphthalenedicarboxylate ion (2,6-NDC) in alkaline D2O was greatly enhanced by the addition of 2,6-bis(1-pyridiniomethyl)naphthalene dibromide (2,6-PMN) as a space-regulator. Formation of a ternary 1:1:1 complex between γ-CD, 2,6-NDC, and 2,6-PMN was confirmed by means of 1H NMR spectroscopy, together with the measurements of induced circular dichroism spectra and UV absorption spectra. Changes in chemical shifts (δ) of the γ-CD protons in the presence of an excess amount of 2,6-PMN with the addition of NDC regioisomers were analyzed by a curve-fitting procedure to give binding constants (K6) for complexation of NDC's with a γ-CD-2,6-PMN binary complex. The K6 values increased in the order of 1,5-NDC 1,4-NDC 1,8-NDC 1,3-NDC 1,6-NDC 2,3-NDC 2,7-NDC 2,6-NDC, indicating that a binary complex of γ-CD with 2,6-PMN is able to recognize the molecular structures of NDC's. The open space between the γ-CD cavity and 2,6-PMN will be favorable for the accommodation of a slender molecule such as 2,6-NDC, but unfavorable for the accommodation of a bulky molecule such as 1,5-NDC.
- Tan, Wei Hua,Ishikura, Takahiro,Maruta, Aya,Yamamoto, Tatsuyuki,Matsui, Yoshihisa
-
-
Read Online
- Preparation and conformational properties of 1,8-bridged fluorenophanes
-
Novel 1,8-bridged fluorenophanes consisting of benzene, benzoquinone, or naphthalene ring have been prepared. Their conformational properties are clarified by the NMR spectra and the X-ray analysis, especially in terms of a shielding effect on 9-protons of the fluorene unit. The dynamic structure was also examined by the variable-temperature NMR spectroscopy.
- Tsuge, Akihiko,Araki, Tadashi,Noguchi, Yuji,Yasutake, Mikio,Moriguchi, Tetsuji,Sakata, Kazunori
-
-
Read Online
- Design, synthesis and biological evaluation of low molecular weight CXCR4 ligands
-
The chemokine receptor CXCR4/stromal cell-derived factor-1 (SDF-1: CXCL12) signaling axis represents a crucial drug target due to its relevance to several diseases such as HIV-1 infection, cancer, leukemia, and rheumatoid arthritis. With the aim of enhancing the binding affinity and anti-HIV activity of a potent CXCR4 ligand as a lead, 23 low molecular weight compounds containing dipicolylamine (Dpa) and cyclam cationic moieties with varying spacers and spatial positioning were designed, synthesized and biologically evaluated. All of the synthesized compounds screened at 1.0 μM in the NanoBRET assay system exhibited >70% inhibition of the binding of a competitive probe TAMRA-Ac-TZ14011 (10 nM) to CXCR4 in the presence of zinc (II) ion. Furthermore, selected compounds 3, 8, 9, 19 and 21 with spatial distances between the next carbon to Dpa and the next carbon to cyclam within the range of 6.5–7.5 ? showed potent binding affinity selective for CXCR4 with IC50 values of 1.6, 7.9, 5.7, 3.5 and 4.5 nM, respectively, with corresponding high anti-HIV activity with EC50s of 28, 13, 21, 28 and 61 nM, respectively, in the presence of zinc (II) ion. Some compounds with remarkably more potent CXCR4-binding affinity than that of an initial lead were obtained. These compounds interact with different but overlapping amino acid residues of CXCR4. The present studies have developed new low molecular weight CXCR4 ligands with high CXCR4-binding and anti-HIV activities, which open avenue into the development of more potent CXCR4 ligands.
- Sakyiamah, Maxwell M.,Kobayakawa, Takuya,Fujino, Masayuki,Konno, Makoto,Narumi, Tetsuo,Tanaka, Tomohiro,Nomura, Wataru,Yamamoto, Naoki,Murakami, Tsutomu,Tamamura, Hirokazu
-
supporting information
p. 1130 - 1138
(2019/02/16)
-
- Facile synthesis of fluorescent distyrylnaphthalene derivatives for bioapplications
-
A series of novel 2,6-bis(4-aminostyryl)naphthalene based derivatives were synthesized and their spectroscopic properties investigated. Due to their low cytotoxicity, suitable optical properties and potential affinity towards biological structures these d
- ?ukasik, Beata,Milczarek, Justyna,Pawlowska, Roza,Zurawiński, Remigiusz,Chworos, Arkadiusz
-
supporting information
p. 6977 - 6980
(2017/08/01)
-
- Electronic Coupling between Two Covalently Bonded Dimolybdenum Units Bridged by a Naphthalene Group
-
Using 2,6-naphthalenedicarboxylate and its thiolated derivatives as bridging ligands, three Mo2 dimers of the type [Mo2(DAniF)3](E2CC10H6CE2)[Mo2(DAniF)3] (DAniF = N,N′-di-p-anisylformamidinate; E = O, S) have been synthesized and characterized by X-ray diffraction. These compounds can be generally formulated as [Mo2]-naph-[Mo2], where the complex unit [Mo2] ([Mo2(DAniF)3(μ-E2C)]) functions as an electron donor (acceptor) and the naphthalene (naph) group is the bridge. The mixed-valence (MV) complexes, generated by one-electron oxidation of the neutral precursors, display weak, very broad intervalence charge-transfer absorption bands in the near-to-mid-IR regions. The electronic coupling matrix elements for the MV complexes, Hab = 390-570 cm-1, are calculated from the Mulliken-Hush equation, which fall between those for the phenyl (ph) and biphenyl (biph) analogues reported previously. The three series consisting of three complexes with the same [Mo2] units exhibit exponential decay of Hab as the bridge changes from ph to biph via naph, with decay factors of 0.21-0.17 ?-1. Therefore, it is evidenced that while the extent of the bridge conjugacy varies, the electronic coupling between the two [Mo2] units is dominated by the Mo2···Mo2 separation. The absorption band energies for metal-to-ligand charge transfer are in the middle of those for the ph and biph analogues, which is consistent with variation of the HOMO-LUMO energy gaps for the complex series. These results indicate that the interplay of the bridge length and conjugacy is to affect the enegy for charge transfer crossing the intervening moiety, in accordance with a superechange mechanism.
- Zhu, Guang Yuan,Meng, Miao,Tan, Ying Ning,Xiao, Xuan,Liu, Chun Y.
-
supporting information
p. 6315 - 6322
(2016/07/06)
-
- Gold(I) styrylbenzene, distyrylbenzene, and distyrylnaphthalene complexes: High emission quantum yields at room temperature
-
One gold(I)-substituted styrylbenzene, six digold(I) distyrylbenzenes, one tetragold distyrylbenzene, and four digold distyrylnaphthalene complexes were synthesized using base-promoted auration, alkynylation, triazolate formation, and Horner-Wadsworth-Emmons reactions. The gold(I) fragments are either σ-bonded to the aromatic system, or they are attached through an alkynyl or triazolate spacer. Product formation was monitored using 31P{ 1H} NMR spectroscopy. Systems in which gold(I) binds to the central benzene ring or the terminal phenyl rings were designed. All of these complexes have strong ultraviolet absorptions and emit blue light. The position of the gold(I) attachment influences the luminescence efficiency. Complexes with two gold(I) fragments attached to the ends of the conjugated system have fluorescence quantum yields up to 0.94, when using 7-diethylamino-4- methylcoumarin as the emission standard. Density-functional theory calculations on three high-yielding emitters suggest that luminescence originates from the distyrylbenzene or -naphthalene bridge. Copyright
- Gao, Lei,Niedzwiecki, Daniel S.,Deligonul, Nihal,Zeller, Matthias,Hunter, Allen D.,Gray, Thomas G.
-
scheme or table
p. 6316 - 6327
(2012/06/30)
-
- Secondary interactions in crystals of all ten isomers of Di(bromomethyl)naphthalene
-
The packing of all ten isomers of di(bromomethyl)naphthalene is analysed; nine of the structures were determined here, one (the 1,8-isomer) was already known. The 1,5- and 2,6-isomers display crystallographic inversion symmetry and the 2,7-isomer mirror symmetry through the central bond. For the 1,2-, 1,7- and 2,7-isomers, the bromomethyl groups point to the same side of the ring system, and for all other isomers to opposite sides. As expected, the molecules are linked into aggregates by various types of interactions: weak hydrogen bonds CH...Br, Br...Br interactions, CH...π contacts, π ...π stacking and Br...π contacts. The weak hydrogen bonds tend to be numerous but relativelyi; long, and do not combine to form readily recognisable patterns; a more readily assimilated view of the packing is based on the Br...Br interactions, which are observed for all isomers except 1,7 and 2,3, and in some cases lead to aggregation to form quadrilaterals or chains. With decreasing frequency, the interactions π ...π, C-H...π and Br...π are observed, but the latter are rare (just two examples) and very asymmetric, with contacts to only one or two carbons.
- Jones, Peter G.,Kus, Piotr
-
experimental part
p. 433 - 444
(2010/10/01)
-
- Unique behavior of 2,6-bis(bromomethyl)naphthalene as a highly active organic DNA crosslinking molecule
-
Among 14 bis-halomethylated naphthalenes and quinolines, 2,6-bis(bromomethyl)naphthalene was found to have highly active crosslinking activity on DNA. The unique behavior of high microbial mutagenicity, even though it had a low propensity to form double-strands in linearized plasmid DNA, suggested that it would offer a new seed, capable of forming intrastrand crosslinks similar to cisplatin. The electron withdrawal extent of the halogen atoms, the substitution patterns of two halomethyl groups, and the introduction of a nitrogen atom into the aromatic nucleus had remarkable effects on the activity of the molecule.
- Higashi, Toshinori,Uemura, Koichi,Inami, Keiko,Mochizuki, Masataka
-
supporting information; experimental part
p. 3568 - 3571
(2009/09/27)
-
- Synthesis of novel amide-crownophanes and Schiff base-crownophanes based on p-phenylene, 2,6-naphthalene, and 9,10-anthracene
-
(Chemical Equation Presented) The novel macrocyclic diamides 11-13, 16-18 are obtained in 45-66% yields by the reaction of dipotassium salts 10a-c and 15 with each of 1,4-di(bromomethyl)benzene 4, 2,6-di(bromomethyl)naphthalene 6 and 9,10-di(bromomethyl)anthracene 8, repectively, in boiling DMF. On the other hand, the new macrocyclic Schiff bases 28 and 29 are obtained in 44% and 42% yields by heating the appropriate bis-amines 25b, 26b with the corresponding bis-aldehydes 21, 22, respectively, in refluxing acetic acid under high-dilution conditions.
- Muathen, Hussni A.,Aloweiny, Nour A. M.,Elwahy, Ahmed H. M.
-
scheme or table
p. 656 - 663
(2009/12/01)
-
- Highly enantioselective and practical cinchona-derived phase-transfer catalysts for the synthesis of α-amino acids
-
A new class of naphthalene-based dimeric cinchona alkaloids 1 are very efficient and practical phase-transfer catalysts in the alkylation of a glycine derivative. The mild reaction conditions and the high catalytic efficiency (high yields and ee values) could make these alkaloids practical catalysts in the industrial synthetic process for natural and nonnatural chiral α-amino acids.
- Park, Hyeung-Geun,Jeong, Byeong-Seon,Yoo, Mi-Sook,Lee, Jeong-Hee,Park, Mi-Kyoung,Lee, Yeon-Ju,Kim, Mi-Jeong,Jew, Sang-Sup
-
p. 3036 - 3038
(2007/10/03)
-
- Methyl and Dimethyl Derivatives of Tetrathionaphthalene and Tetraselenonaphthalene as Novel Electron Donors
-
Monomethyl and dimethyl tetrathionaphthalenes and tetraselenonaphthalenes have been developed as modified electron donors. Introduction of methyl groups is very helpful in enhancing the inherent low solubilities of the parent compounds. In the cyclic voltammograms, they show two reversible redox waves, whose first and second oxidation potentials are gradually lowered with the increasing number of the introduced methyl groups. They all are able to form charge-transfer complexes with tetracyanoquinodimethane. Irrespective of the chalcogen kind of the donor, the complexes of the dimethyl derivatives are conductive, while those of the monomethyl derivatives are insulating. The different conductivities are explained by the difference of their crystal structures, which are studied by infrared spectroscopy.
- Kodama, Takashi,Kodani, Mie,Takimiya, Kazuo,Aso, Yoshio,Otsubo, Tetsuo
-
p. 287 - 292
(2007/10/03)
-
- Synthesis, molecular modeling, and K+ channel-blocking activity of dequalinium analogues having semirigid linkers
-
Dequalinium [1,1'-(decane-l,10-diyl)bis(2-methyl-4-aminoquinolinium)] is an effective blocker of the small conductance Ca2+activated K+ channel. It has been shown that the number of methylene groups in the alkyl chain linking the two quinolinium rings of this type of molecule is not critical for activity. To further investigate the role of the linker, analogues of dequalinium have been synthesized, in which the alkyl chain has been replaced by CH2XCH2 where X is a rigid or semirigid group containing aromatic rings. The compounds have been tested for blockade of the slow after- hyperpolarization on rat sympathetic neurons. The most potent compounds have X = phenanthryl, fluorenyl, cis-stilbene, and C6H4(CH2)(n)C6H4 where n = 0-4. The conformational preferences of the compounds were investigated using the XED/COSMIC molecular modeling system. Although there is some dependence of the potency of the analogue on the conformational properties of the linker (X), overall, X groups having substantial structural differences are tolerated. It seems that X provides a support for the two quinolinium groups and does not interact with the channel directly. The intramolecular separation between the quinolinium rings, which is provided by rigid groups X, is not critical for activity; this may be attributed to the residual conformational mobility of the heterocycles and to the extensive delocalization of the positive charge. These two factors may permit favorable contacts between the quinolinium groups and the channel over a range of intramolecular separations.
- Rosa, Joaquin Campos,Galanakis, Dimitrios,Ganellin, C. Robin,Dunn, Philip M.
-
p. 4247 - 4254
(2007/10/03)
-
- Quaternary ammonium compounds having muscle relaxation activity
-
A quaternary ammonium having a muscle relaxation activity compound represented by the formula (I): STR1 wherein R1 represents a methylene, a lower alkylenoxy, a lower alkenylene, a lower alkynylene, --CO--, --COO--, a lower alkylene carbonyloxy, --CH(OR5)--, a lower alkylenecarbonyl, a hydroxy lower alkylene, --O--, --S--, --SO--, or --SO2 --; R2 represents a hydrogen atom, a hydroxy lower alkyl, an aldehyde, a lower alkyl carbonyl, --NO2, or --NHR6 ; R3 represents a hydrogen atom of a group --R1 --(CH2)a --[CH(CH2 A)--CH2 ]b --A; R4 represents an anion; R5 and R6 represent a hydrogen atom or a acetyl; A represents a quaternary ammonium group; a represents an integer of 1 to 8; b represents 0 or 1; m represents an integer of 1 to 4; and (Z) represents a trivalent benzene ring, a trivalent naphthalene ring, a trivalent diphenyl or a trivalent ethane radical.
- -
-
-
- Photobromination of Side-Chain Methyl Groups on Arenes with N-Bromosuccinimide - Convenient and Selective Syntheses of Bis(bromomethyl)- and (Bromomethyl)methylarenes -
-
Photobromination of side-chain methyl groups on arenes with N-bromosuccinimide (NBS) was investigated.Visible light irradiation in benzene solvent was extremely effective in increasing the selectivity of the reaction and the efficiency for product purification.The photobromination of 1,4-, 1,8, 2,3-, and 2,6-dimethylnaphthalenes, 4,4'-dimethylbiphenyl, and p-xylene with 2.2 mol equivalents of NBS quantitatively afforded the corresponding bis(bromomethyl)arenes, respectively.The (bromomethyl)methylarenes were also obtained in good yields in the photobromination reactions of the above dimethylarenes with 1.1 mol equivalents of NBS.
- Futamura, Shigeru,Zong, Zhi-Min
-
p. 345 - 348
(2007/10/02)
-
- A New General Synthesis of Polycyclic Aromatic Compounds Based on Enamine Chemistry
-
Alkylation of enamines and enamine salts by benzylic and (β-haloethyl)aryl halides, respectively, followed by acidic cyclodehydration and dehydrogenation provides an efficient synthetic approach to a wide range of polycyclic aromatic compounds of diverse structural types.Specific polycyclic hydrocarbons synthesized by this route include benzo- and benzofluorene, 7H-dibenzo-, 13H-dibenzo-, and 13H-dibenzofluorene, 15H-tribenzofluorene, dibenzochrysene, benzopentaphene, indenofluorene, fluorenofluorene, octahydrodibenzanthracene, dibenzanthracene, octahydrodibenzanthracene, dibenzanthracene, picene, benzopicene, 1H-benzaceanthrylene, and 4H-cyclopentachrysene.This method with appropriate modifications appears to be potentially broader in scope than established traditional methods of polycyclic hydrocarbon synthesis.
- Harvey, Ronald G.,Pataki, John,Cortez, Cecilia,Raddo, Pasquale Di,Yang, ChengXi
-
p. 1210 - 1217
(2007/10/02)
-
- (4,4')BENZOPHENONO(2,6)NAPHTHALENOPHANE: SYNTHESIS, STRUCTURE, AND SPECTROSCOPIC STUDY
-
The synthesis of (4,4')benzophenono(2,6)naphthalenophane (1), the parent member of a series of stacked senzitizer-acceptor cyclophanes, is reported along with its x-ray structure and the absorption and emission spectra.
- Givens, Richard S.,Venkatramanan, M. K.
-
p. 2187 - 2190
(2007/10/02)
-
- SYNTHESE PHOTOCHIMIQUE D'HYDROCARBURES POLYCYCLIQUES AROMATIQUES ET ETUDE EN RMN-1H DES PROTONS DE BAIE. EFFECTS DE SOLVANT SPECIFIQUES ET EFFECTS NUCLEAIRES OVERHAUSER.
-
"Photochemical synthesis of polycyclic aromatic hydrocarbons and NMR-1H study of bay protons.Specific solvent effects and nuclear Overhauser effects".Dinaphthoanthracene (4a),9-bromo-dinaphthoanthracene (4b), 9-methyldinaphthoanthracene (4c), benzonaphthochrysene (7), benzonaphthoanthracene (3), naphthochrysene (9) and dibenzonaphthochrysene (12) have been synthesized by the photocyclodehydrogenation of 1,2-diarylethylenes (5,8) and bis (arylvinyl)arenes (6,10).The NMR study has been mainly focused on the bay protons involved in specific solvent effects Table 4) and nuclear Overhauser effects (Table 5).
- Brison, Jean,Bakker, Claude de,Defay, Nicole,Geerts-Evrard, France,Marchant, Marie-Jeanne,Martin, Richard H.
-
p. 901 - 912
(2007/10/02)
-