4469-80-1Relevant articles and documents
Liquid crystalline behaviour of polymer networks based on segmented chain mesogenic polymers
Aurino,Caruso,Pragliola,Roviello,Sirigu
, p. 99 - 109 (1995)
The synthesis of some crosslinked polymers based on a segmented-chain polymeric mesogen containing variable amounts of a side chain substituent is reported. The unswollen networks show thermotropic mesomorphism of nematic character whose stability decreases with increasing substitution and crosslink density. Depending on the same parameters, the swollen networks may show optical anisotropy at room temperature whose origin is attributed to phase separation.
Investigation of hydro-lipophilic properties of n-alkoxyphenylhydroxynaphthalenecarboxamides ?
Kapustikova, Iva,Bak, Andrzej,Gonec, Tomas,Kos, Jiri,Kozik, Violetta,Jampilek, Josef
, (2018/07/10)
The evaluation of the lipophilic characteristics of biologically active agents is indispensable for the rational design of ADMET-tailored structure–activity models. N-Alkoxy-3-hydroxynaphthalene-2-carboxanilides, N-alkoxy-1-hydroxynaphthalene-2-carboxanilides, and N-alkoxy-2-hydroxynaphthalene-1-carboxanilides were recently reported as a series of compounds with antimycobacterial, antibacterial, and herbicidal activity. As it was found that the lipophilicity of these biologically active agents determines their activity, the hydro-lipophilic properties of all three series were investigated in this study. All 57 anilides were analyzed using the reversed-phase high-performance liquid chromatography method for the measurement of lipophilicity. The procedure was performed under isocratic conditions with methanol as an organic modifier in the mobile phase using an end-capped non-polar C18 stationary reversed-phase column. In the present study, a range of software lipophilicity predictors for the estimation of clogP values of a set of N-alkoxyphenylhydroxynaphthalenecarboxamides was employed and subsequently cross-compared with experimental parameters. Thus, the empirical values of lipophilicity (logk) and the distributive parameters (π) were compared with the corresponding in silico characteristics that were calculated using alternative methods for deducing the lipophilic features. To scrutinize (dis)similarities between the derivatives, a PCA procedure was applied to visualize the major differences in the performance of molecules with respect to their lipophilic profile, molecular weight, and violations of Lipinski’s Rule of Five.
Synthesis and mesomorphic properties of 2,4-bis(4′-n-pentyloxybenzoyloxy)- benzylidine-4″- n-alkoxyaniline
Hamad, Wali M.,Azeez, Hashim J.,Al-Dujaili, Ammar H.
, p. 67 - 75 (2017/09/25)
The synthesis and mesomorphic properties of a new series of 2,4-bis(4′-npentyloxybenzoyloxy)- benzylidine-4″ -n-alkoxyaniline (DC5An) are reported. The molecular structure of compounds was confirmed by FTIR, 1H-NMR, 13C-NMR, mass spectroscopy and elemental analysis. The mesomorphic properties were studied by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) measurements. All compounds of the series exhibit nematic (N) and smectic C (SmC) phases. The first four homologues (DC5A1-DC5A4) display a N mesophase, whereas the highest homologues (DC5A5-DC5A10) exhibit an enantiotropic dimorphism N and SmC phases. The mesomorphic properties of the present series are compared and discussed with other structurally related series.
Inclusion complexes of a new family of non-ionic amphiphilic dendrocalix[4]arene and poorly water-soluble drugs naproxen and ibuprofen
Khan, Khalid,Lal Badshah, Syed,Ahmad, Nasir,Rashid, Haroon Ur,Mabkhot, Yahia
, (2017/06/08)
The inclusion complexes of a new family of nonionic amphiphilic calix[4]arenes with the anti-inflammatory hydrophobic drugs naproxen (NAP) and ibuprofen (IBP) were investigated. The effects of the alkyl chain's length and the inner core of calix[4]arenes on the interaction of the two drugs with the calix[4]arenes were explored. The inclusion complexes of Amphiphiles 1a-c with NAP and IBP increased the solubility of these drugs in aqueous media. The interaction of 1a-c with the drugs in aqueous media was investigated through fluorescence, molecular modeling, and 1H-NMR analysis. TEM studies further supported the formation of inclusion complexes. The length of lipophilic alkyl chains and the intrinsic cyclic nature of cailx[4]arene derivatives 1a-c were found to have a significant impact on the solubility of NAP and IBP in pure water.
Properties of liquid crystals and Cu2+ recognition based on Schiff bases
Liu, Zhilian,Yu, Zhenning,Zhang, Jian,Zhang, Shuxiang
, p. 11 - 19 (2016/02/19)
Two series of new Schiff base compounds were synthesized. For Schiff base compounds with a pyridine nitrogen atom in 4-position (7a-e), their supramolecular hydrogen bonding complexes show good liquid crystal properties. However, no liquid crystal property is observed for 8a-e. Results of theoretical calculations demonstrate that it is the intermolecular hydrogen bond of Schiff base compounds (8a-e) that prevents the formation of supramolecular hydrogen bonding. The Schiff base compounds, with terminal alkoxy chains, can recognize Cu2+ selectively with a color change. Nevertheless, others cannot recognize Cu2+.
Synthesis and Biological Evaluation of N-Alkoxyphenyl-3-hydroxynaphthalene-2-carboxanilides
Gonec, Tomas,Zadrazilova, Iveta,Nevin, Eoghan,Kauerova, Tereza,Pesko, Matus,Kos, Jiri,Oravec, Michal,Kollar, Peter,Coffey, Aidan,O'Mahony, Jim,Cizek, Alois,Kralova, Katarina,Jampilek, Josef
, p. 9767 - 9787 (2015/08/06)
A series of fifteen new N-alkoxyphenylanilides of 3-hydroxynaphthalene-2-carboxylic acid was prepared and characterized. Primary in vitro screening of the synthesized compounds was performed against Staphylococcus aureus, three methicillin-resistant S. aureus strains, Mycobacterium tuberculosis H37Ra and M. avium subsp. paratuberculosis. Some of the tested compounds showed antibacterial and antimycobacterial activity against the tested strains comparable with or higher than that of the standards ampicillin or rifampicin. 3-Hydroxy-N-(2-propoxyphenyl)naphthalene-2-carboxamide and N-[2-(but-2-yloxy)-phenyl]-3-hydroxynaphthalene-2-carboxamide had MIC = 12 μM against all methicillin-resistant S. aureus strains; thus their activity is 4-fold higher than that of ampicillin. The second mentioned compound as well as 3-hydroxy-N-[3-(prop-2-yloxy)phenyl]-naphthalene-2-carboxamide had MICs = 23 μM and 24 μM against M. tuberculosis respectively. N-[2-(But-2-yloxy)phenyl]-3-hydroxynaphthalene-2-carboxamide demonstrated higher activity against M. avium subsp. paratuberculosis than rifampicin. Screening of the cytotoxicity of the most effective antimycobacterial compounds was performed using THP-1 cells, and no significant lethal effect was observed for the most potent compounds. The compounds were additionally tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. N-(3-Ethoxyphenyl)-3-hydroxynaphthalene-2-carboxamide (IC50 = 4.5 μM) was the most active PET inhibitor. The structure-activity relationships are discussed.
Dual thermo- and light-responsive nanorods from self-assembly of the 4-propoxyazobenzene-terminated poly(N-isopropylacrylamide) in aqueous solution
Xue, Xiaoqiang,Yang, Jing,Huang, Wenyan,Yang, Hongjun,Jiang, Bibiao,Li, Fang,Jiang, Yun
, p. 195 - 204 (2015/08/18)
Abstract Both temperature and light stimuli-responsive 4-propoxyazobenzene-terminated poly(N-isopropylacrylamide)s (PNIPAMs) were successfully synthesized by the atom transfer radical polymerization (ATRP) of NIPAM. 1H NMR and UV-vis absorption spectra indicated rapid photoisomerization rate of 4-propoxyazobenzene moiety. Interestingly, the lower critical solution temperature (LCST) for PNIPAM aqueous solution clearly decreased after UV irradiation, and the repeated LCST difference (ΔTmaxy = 5°C) depended on both the number-average molecular weight and amount of azobenzene chromophore. Dynamic light scattering (DLS) and static light scattering (SLS) measurements showed that the PNIPAM aqueous solution could self-assemble into nano-micelles with 4-propoxyazobenzene as the hydrophobic cores and PNIPAM chains as the hydrophilic shells. UV irradiation induced the increase of particle size due to the formation of much looser cores of cis-azobenzene. TEM images showed the presence of both nanorods and spherical micelles. After UV irradiation, the unstable spherical micelles transformed to metastable nanorods, then to longer rods, and finally the longer rods began to transform to flake-like particles via horizontal inter-rod aggregation above LCST.
Enhanced Reactivity of Aerobic Diimide Olefin Hydrogenation with Arylboronic Compounds: An Efficient One-Pot Reduction/Oxidation Protocol
Santra, Surojit,Guin, Joyram
supporting information, p. 7253 - 7257 (2015/11/25)
A catalyst-free and efficient method for simultaneous olefin hydrogenation and oxidation of arylboronate esters to phenols with hydrazine hydrate and molecular oxygen is presented. The process is based on the utilization of a readily available Lewis acidic arylboron compound, which evades common problems associated with the catalyst-free aerobic hydrogenation of olefins with diimide. Using an operationally simple procedure, the protocol smoothly delivers phenol derivatives and various alkanes in excellent yields with remarkable functional group compatibility. The method allows the reaction to be scaled up to 1 g of the starting materials.
Magnetically recoverable catalytic Co-Co2B nanocomposites for the chemoselective reduction of aromatic nitro compounds
Vernekar, Amit A.,Patil, Sagar,Bhat, Chinmay,Tilve, Santosh G.
, p. 13243 - 13250 (2013/09/02)
Magnetically recoverable and recyclable Co-Co2B nanocomposites are described for the catalytic and chemoselective reduction of nitroarenes using two different hydrogen sources, sodium borohydride and hydrazine hydrate. Both the systems display an interesting chemoselective reduction switch. The kinetics of reduction of nitroaromatics were studied for the first time and follow nitroreductase enzyme-like kinetics with exceedingly high Kcat (5.2 × 104 s-1) and Kcat/KM (4.4 × 106 M-1 s-1) values, reaching the state of catalytic perfection. The recyclability of the catalyst system was studied by magnetically recovering the nano composite catalyst.
Liquid-crystalline polymorphism of 4-heptyloxybenzylidene-4′- alkyloxyanilines and their phase equilibrium with 4-octyloxyphenyl 4-nitrobenzoate
Godzwon, Joanna,Sienkowska, Monika J.,Galewski, Zbigniew
scheme or table, p. 75 - 82 (2012/04/04)
This paper describes the synthesis and liquid-crystalline properties of the homologous series of 4-heptyloxybenzylidene-4′-alkyloxyanilines (7-n). Six of them are presented for the first time. Based on the polarization microscopy (POM and TOA methods) and the calorimetric (DSC) measurements following polymorphism has been detected: nematic, smectic C and smectic I mesophases. The presence of these mesophases was confirmed by the miscibility method, using 4-octyloxyphenyl 4-nitrobenzoate and terephtal-bis (4-butyloaniline) as a mesophase references. Extraordinary results have been found in the mixtures of the investigated compounds with 4-octyloxyphenyl 4-nitrobenzoate; Induced smectic A has been observed, which is connected with very strong intermolecular interactions. Additionally destabilization of nematic and smectic C phases was visible.
