Synthesis,structure and biological activity studies of 2‐[(1H‐1,2,4‐triazol‐1‐yl)methyl]‐1‐aryl)‐3‐ferrocenyl prop‐2‐en‐1‐one derivatives

Fifteen new ferrocene derivatives containing 1H‐1,2,4‐triazole moiety were synthesized in various yields by the condensation of ferrocenecarboxaldehyde with 1‐aryl‐3‐(1H‐1,2,4‐triazo‐1‐yl)‐propen‐1‐ones in toluene. Their structures have been confirmed by ¹H NMR, IR, MS and elemental analysis. In addition, the crystal structure of 4l was determined. The antifungal and plant growth regulatory activities of the title compounds are discussed. Copyright © 2005 John Wiley & Sons, Ltd.     

Synthesis,Bioactivity, and the Anion‐Binding Property of 2‐Sulfydryl‐1,3,4‐thiodiazole Derivatives

Two new compounds ( 1 and 2 ) containing 2‐sulfydryl‐1,3,4‐thiodiazole have been synthesized and optimized. They both showed wide antibacterial activity for colon bacillus, Staphylococcus aureus, S. albus, dysentery bacillus and inferior activity for Bacillus subtilis. In addition, their binding properties were evaluated for biologically important anions (F^–, Cl^–, Br^–, I^–, AcO^–, and H₂PO₄^–) by theoretical investigation, UV–vis, fluorescence, and ¹H NMR titration experiments, and they displayed strong binding ability for H₂PO₄^– without the interference of other anions tested. Especially the binding ability of compound 2 containing anthracene with H₂PO₄^– was 1000 times stronger than that of compound 1 containing nitrobenzene. Two compounds based on 2‐sulfydryl‐1,3,4‐thiodiazole have both properties of anion recognition and antibacterial activity.     

Improved Spectral Coverage and Fluorescence Quenching in Donor–acceptor Systems Involving Indolo[3‐2‐b]carbazole and Boron‐dipyrromethene or Diketopyrrolopyrrole

A novel π‐conjugated triad and a polymer incorporating indolo[3,2‐b]‐carbazole (ICZ) and 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) were synthesized via a Sonogashira coupling. Compared to the parent BODIPY the absorption and fluorescence spectrum were for both compounds broader and redshifted. The redshift of the fluorescence and the decrease of the fluorescence quantum yield and decay time upon increasing solvent polarity were attributed to the formation of a partial charge‐transfer state. Upon excitation in the ICZ absorption band the ICZ fluorescence was quenched in both compounds mainly due to energy transfer to the BODIPY moiety. In a similar ICZ–π–DPP polymer (where DPP is diketopyrrolopyrrole), a smaller redshift of the absorption and fluorescence spectra compared to the parent DPP was observed. A less efficient quenching of the ICZ fluorescence in the ICZ–π–DPP polymer could be related to the unfavorable orientation of the transition dipoles of ICZ and DPP. The rate constant for energy transfer was for all compounds an order of magnitude smaller than predicted by Förster theory. While in a solid film of the triad a further redshift of the absorption maximum of nearly 100 nm was observed, no such shift was observed for the ICZ–π–BODIPY polymer.     

A new approach to the synthesis of 2‐aryl‐substituted benzimidazoles,quinazolines, and other related compounds and their antibacterial activity

A new synthesis method of benzimidazoles, dihydroquinazolines, and other related compounds containing a 2,4‐dihydroxyphenyl moiety was elaborated. Their structures were identified from elemental, infrared, ¹H NMR, ¹³C NMR, and mass spectra analyses. The minimal inhibitory concentration values of the compounds toward eight reference bacterial strains were determined by the two‐fold serial microdilution broth method. The compounds exhibited substantial inhibitory effects against the Gram‐positive strains tested contrary to Gram‐negative ones. The compounds of imidazopyridine, N‐methylbenzimidazole, and dihydroquinazoline structures exhibited the largest activity. The magnification of covering a two‐nitrogen atom heterocyclic ring fused to a benzene one decreases the biological effect. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:265–275, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21012     

On the π‐Electron Distribution in Biphenylene Analogues

The bonding situation in a series of biphenylene analogues – benzo[b]biphenylene and its dication, 4,10‐dibromobenzo[b]biphenylene, naphtho[2,3‐b]biphenylene and its dianion, benzo[a]biphenylene, (biphenylene)tricarbonylchromium, benzo[3,4]cyclobuta[1,2‐c]thiophene, benzo[3,4]cyclobuta[1,2‐c]thiophene 2‐oxide, benzo[3,4]cyclobuta[1,2‐c]thiophene 2,2‐dioxide, 4,10‐diazabenzo[b]biphenylene, biphenylene‐2,3‐dione, benzo[3,4]cyclobuta[1,2‐b]anthracene‐6,11‐dione, and 3,4‐dihydro‐2H‐benzo[3,4]cyclobuta[1,2]cycloheptene – where one of the two benzo rings of biphenylene is replaced by a different π‐system (B) was investigated on the basis of the NMR parameters of these systems. From the vicinal ¹H,¹H spin‐spin coupling constants, the electronic structure of the remaining benzo ring (A) is derived via the Q‐value method. It is found that increasing tendency of B to tolerate exocyclic double bonds at the central four‐membered ring of these systems favors increased π‐electron delocalization in the A ring. The analysis of the chemical shifts supports this conclusion. NICS (nucleus‐independent chemical shift) values as well as C,C bond lengths derived from ab initio calculations are in excellent agreement with the experimental data. The charged systems benzo[b]biphenylene dication and naphtho[2,3‐b]biphenylene dianion ( 7 ²⁻) are also studied by ¹³C NMR measurements. The charge distribution found closely resembles the predictions of the simple HMO model and reveals that 7 ²⁻ can be regarded as a benzo[3,4]cyclobuta[1,2‐b]‐substituted anthracene dianion. It is shown that the orientation of the tricarbonylchromium group in complexes of benzenoid aromatics can be derived from the vicinal ¹H,¹H coupling constants.     

Synthesis,Characterization, and Herbicidal Activities of New 1,3,4‐Oxadiazoles, 1,3,4‐Thiadiazoles,and 1,2,4‐Triazoles Derivatives Bearing (R)‐5‐Chloro‐3‐fluoro‐2‐phenoxypyridine

Synthesis of some novel 1,2,4‐triazoles, 1,3,4‐oxadiazoles and 1,3,4‐thiadiazoles bearing a (R) 5‐(1‐(4‐(5‐chloro‐3‐fluoropyridin‐2‐yloxy)phenoxy)ethyl) unit, as a moiety of commercial herbicide, using their thiosemicarbazides in an alkaline, iodine and acidic media is reported, respectively. The structure of the synthesized compounds was characterized by IR, ¹H, ¹³C NMR spectroscopic data, and elemental analyses. The herbicidal activities of synthesized compounds were evaluated against Echinochloa cruss‐galli, Avena fatua, and Sorgum halepense weeds. Compounds 7 and 12a showed potential herbicidal activity against gramineous weeds. Our results may provide some guidance for synthesis development of some novel oxa or thiadiazole and triazole‐based herbicidal lead structures.     

One‐step synthesis of 6‐acetamido‐3‐(N‐(2‐(dimethylamino) ethyl) sulfamoyl) naphthalene‐1‐yl 7‐acetamido‐4‐hydroxynaphthalene‐2‐sulfonate and its characterization with 1D and 2D NMR techniques

A one‐step method was reported for the synthesis of 6‐acetamido‐3‐(N‐(2‐(dimethylamino) ethyl) sulfamoyl) naphthalene‐1‐yl 7‐acetamido‐4‐hydroxynaphthalene‐2‐sulfonate by treating 7‐acetamido‐4‐hydroxy‐2‐naphthalenesulfonyl chloride with equal moles of N, N‐dimethylethylenediamine in acetonitrile in the presence of K₂CO₃. The chemical structure of the obtained compounds was characterized by MS, FTIR, ¹H NMR, ¹³C NMR, gCOSY, TOCSY, gHSQC, and gHMBC. The chemical shift differences of ¹H and ¹³C being δ 0.04 and 0.2, respectively, were unambiguously differentiated. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and Antifungal Activity of Novel Chiral α-Aminophosphonates Containing Fluorine Moiety

Chiral α-aminophosphonates were synthesized using （R） or （S）-1-phenylethylamine in the presence of BF3·Et2O under microwave irradiation in moderate to good yields. The new compounds were identified by ^1H NMR, ^19F NMR, IR and elemental analysis. Their antifungal activities were evaluated and some compounds were found to exhibit excellent antifungal activities. To the best of our knowledge, this is the first report on antifungal activity of chiral α-aminophosphonates containing fluorine moiety.     

One‐Pot Regioselective Synthesis of Novel Oximino Ester‐Containing 1‐Aryl‐4‐chloro‐3‐oxypyrazoles as Potential Fungicides

A novel, functional‐group‐tolerant, and highly regioselective one‐pot synthesis of six 4‐chloro‐1‐aryl‐3‐oxypyrazoles, 8a – 8f , containing an oximino ester moiety has been developed. Their structures were characterized by ¹H‐ and ¹³C‐NMR, IR, MS, and elemental analyses. The regioselectivity of the reaction was also determined by single‐crystal X‐ray diffraction analysis of product 8d . The reaction pathway, proposed with the aid of DFT calculations, likely proceeds via a DMF‐catalyzed mechanism, which involves an electrophilic attack by SOCl₂ and two nucleophilic substitutions by benzyl bromide (BnBr) and Cl^?, respectively, as the key steps. A preliminary in vitro bioassay indicated that most compounds exhibited good fungicidal activities against Sclerotinia sclerotiorum and Gibberella zeae. Especially, 8d and 8e displayed higher or similar fungicidal activities compared with pyraclostrobin at the concentration of 10 μg/ml.     

2-萘-(OCH2CH2)n-金刚胺与6-单取代环糊精衍生物的光诱导电子转移反应

A number of naphthalene donor compounds that possess an adamantanamine binding moiety and an (OCH2CH2)n (nn1, 2, 3, 4, 6, 8) spacer were synthesized. The fluorescence quenching between these donor substrates and mono-6-O-p-nitrobenzoyl-β-cyclodextrin (pNBCD) and mono-6-O-m-nitrobenzoyl-β-cyclodextrin(mNBCD) was studied in detail. It was found that very efficient fluorescence quenching could occur in these supramolecular systems. This quenching was attributed to the photoinduced electron transfer inside the supramolecular assembly between the naphthalene donors and cyclodextrin acceptors. Detailed Stern-Volmer constants were measured and they were partitioned into dynamic Stern-Volmer quenching constants and static binding constants. It was demonstrated that the binding constants between all the naphthalene compounds and cyclodextrins are the same as they possess the same binding site, i.e., adamantanamine.     

Synthesis and biological activities of new 1H‐1,2,4‐triazole alcohol derivatives containing a ferrocenyl moiety

Fourteen new 1H‐1,2,4‐triazole alcohol derivatives containing a ferrocenyl moiety were synthesized. In addition, six unexpected compounds, the hydroxyls of the title compounds, methylated by methanol, were obtained. The structures of all these new compounds were confirmed using ¹H NMR spectra, ¹³C NMR, MS and elemental analyses. Some compounds were also confirmed with IR spectra. The antifungal and plant growth regulatory activities of the title compounds are discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

9,10‐Di­phenyl‐9,10‐epi­dioxy­anthra­cene and 9,10‐di­hydro‐10,10‐di­methoxy‐9‐phenyl­anthracen‐9‐ol

9,10‐Di­phenyl‐9,10‐epi­dioxy­anthracene, C₂₆H₁₈O₂, (I), was accidentally used in a photo­oxy­genation reaction that produced 9,10‐di­hydro‐10,10‐di­methoxy‐9‐phenyl­anthracen‐9‐ol, C₂₂H₂₀O₃, (II). In both compounds, the phenyl rings are approximately orthogonal to the anthracene moiety. The conformation of the anthracene moiety differs as a result of substitution. Intramolecular C—H⃛O interactions in (I) form two approximately planar S(5) rings in each of the two crystallographically independent mol­ecules. The packing of (I) and (II) consists of molecular dimers stabilized by C—H⃛O interactions and of molecular chains stabilized by O—H⃛O interactions, respectively.     

[Hg2(μ‐bpe)(μ‐OAc)2(μ‐SCN)2]n,a New Two‐Dimensional Coordination Polymer Involving Three Simultaneously Bridging Ligands: 1,2‐Bis(4‐pyridyle)ethene,Acetate, and Thiocyanate

A new mercury(II) complex of 1,2‐bis(4‐pyridyle)ethene (bpe) with anionic acetate and thiocyanate ligands has been synthesized and characterized by elemental analysis, IR, ¹H NMR and ¹³C NMR spectroscopy. The single crystal X‐ray analysis shows that the complex is a two‐dimensional polymer with simultaneously bridging 1,2‐bis(4‐pyridyle)ethane, acetate and thiocyanate ligands and basic repeating dimeric [Hg₂(μ‐bpe)(μ‐OAc)₂(μ‐SCN)₂] units. The two‐dimensional system forms a three‐dimensional network by packing via π‐π stacking interactions.     

Crystal and electronic structure of a hexacarbonyldiiron cluster tethered to naphthalene‐2‐thiolate ligands

The structure of the previously reported complex bis(μ‐naphthalene‐2‐thiolato‐κ²S:S)bis(tricarbonyliron)(Fe—Fe), [Fe₂(C₁₀H₇S)₂(CO)₆], has been characterized by X‐ray diffraction. In the solid state, the dinuclear complex adopts a butterfly‐like shape, with an equatorial–axial spatial orientation of the naphthalene groups covalently coupled to the [S₂Fe₂(CO)₆] unit. The asymmetric unit contains three independent [(μ‐naphthalene‐2‐thiolato)₂Fe₂(CO)₆] molecules. These molecules show intermolecular π–π stacking interactions between the naphthalene rings, which was confirmed by Hirshfield surface analysis. The electronic spectrum of the complex recorded in acetonitrile shows a band centered at 350 nm (ϵ = 4.6 × 10³ M⁻¹ cm⁻¹) and tailing into the visible region. This absorption can be attributed to a π→π* electronic transition within the naphthalene moiety and a metal‐based d→d transition.     

Synthesis of Organoselenium‐Modified β‐Cyclodextrins Possessing a 1,2‐Benzisoselenazol‐3(2H)‐one Moiety and Their Enzyme‐Mimic Study

Six novel H₂O‐soluble β‐cyclodextrin derivatives containing a 1,2‐benzisoselenazol‐3(2H)‐one moiety were synthesized by a convenient method in 25–60% yield and characterized by MS, elemental analysis, IR, ¹H‐NMR, and UV/VIS spectroscopy. The conformations of these β‐cyclodextrin derivatives 1 – 6 were analyzed by circular dichroism and fluorescence‐lifetime experiments. The superoxide dismutase (SOD) activities of 1 – 6 were determined by auto‐oxidation of pyrogallol at 25.0° in buffer solution (pH 8.2), giving relatively high SOD activities of up to 121–330 U/mg. Also, the glutathione peroxidase (GPX) activities of hosts 1 – 6 , determined by the method of Wilson at 37° in buffer solution (pH 7.0), show good GPX activities in the range of 0.34–0.86 U/μmol. The mimicking results of the bifunctional artificial enzyme models 1 – 6 were globally compared with regard to their structural and conformational difference.     

Action of Hydrazines on 2‐(2‐Oxindolin‐3‐ylidene)malononitrile, (E,Z)‐Ethyl 2‐cyano‐2‐(2‐oxindolin‐3‐ylidene)acetate and Isatin‐β‐thiosemicarbazone as a Source of Spiro Indoline‐pyrazole Systems

2‐(2‐Oxindolin‐3‐ylidene)malononitrile ( 1a ) or (E,Z)‐ethyl 2‐cyano‐2‐(2‐oxindolin‐3‐ylidene)acetate ( 1b ) or isatin‐β‐thiosemicarbazone ( 1c ) undergoes reactions with prototype hydrazine hydrate itself and some of its simple congeners to give hydrazone derivatives bearing indoline‐2‐one moiety ( 2 ). The hydrazone derivatives ( 2 ) when heated with acetyl acetone or ethyl acetoacetate in dry pyridine afforded the spiro indoline derivatives ( 3a , 3b ). Also, cinnoline derivative ( 9 ) is obtained by action of hydrazine hydrate on the N‐acetyl derivative of ( 6a ). The structures of the newly synthesized compounds were evaluated by IR, ¹H‐NMR spectroscopy, mass spectra and elemental analyses.     

Solid‐Phase Synthesis of Peptide Libraries Combining α‐Amino Acids with Inorganic and Organic Chromophores

The synthesis of two series of peptidic chains composed of bis(terpyridine)ruthenium(II) acceptor units and organic chromophores (coumarin, naphthalene, anthracene, fluorene) by stepwise solid‐phase peptide synthesis (SPPS) techniques is described. The first series of dyads comprises directly amide linked chromophores, while the second one possesses a glycine spacer between the two chromophores. All dyads were studied by UV/Vis and NMR spectroscopy, steady‐state luminescence, luminescence decay and electrochemistry, as well as by DFT calculations. The results of these studies indicate weak electronic coupling of the chromophores in the ground state. Absorpion spectra of all dyads are dominated by metal‐to‐ligand charge‐transfer (MLCT) bands around 500 nm. The bichromophoric systems, especially with coumarin as organic chromophore, display additional strong absorptions in the visible spectral region. All complexes are luminescent at room temperature (³MLCT). Efficient quenching of the fluorescence of the organic chromophore by the attached ruthenium complex is observed in all dyads. Excitation spectra indicate energy transfer from the organic dye to the ruthenium chromophore.     

Synthesis,Dissociation Constants,and Antimicrobial Activity of Novel 2,3‐Disubstituted‐1,3‐thiazolidin‐4‐one Derivatives

In this article, a new series of 2,3‐disubstituted‐1,3‐thiazolidin‐4‐one derivatives have been designed, synthesized, and evaluated as antimicrobial agents. New compounds were prepared by the cyclization reaction of N‐substituted carboxylic acid hydrazide derivatives with mercaptoacetic acid. The structures of the obtained compounds were confirmed by means of IR, ¹H NMR, and ¹³C NMR spectra. The dissociation constants were determined using spectrophotometric method. All synthesized compounds were tested for their in vitro antibacterial and antifungal activities using the broth microdilution method.     

Synthesis,Crystal Structure,and Antibacterial Activity of 1,2,4‐Triazoles and 1,2,4‐Triazol‐3‐one

A straightforward method has been developed for the synthesis of 1,2,4‐triazol‐3‐one 3 and 1,2,4‐triazoles 6a , 6b , 6c , 6d starting from N¹‐substituted‐N¹‐tosylhydrazonates 2 and hydrazine monohydrate. This methodology affords a number of 1,2,4‐triazol‐3‐one 3 and 1,2,4‐triazoles 6a , 6b , 6c , 6d in reasonable yields. The structures of all new compounds were elucidated using infrared, ¹H and ¹³C NMR, high‐resolution mass spectrometry, elemental analysis, and the X‐ray crystallography (for compounds 3 and 6a ). Some of the newly synthesized compounds were screened for their antibacterial activity.     

Synthesis and Insecticidal Evaluation of Novel Phthalic Diamides Containing 1,2,3‐Triazoles via Click Reaction

A series of novel phthalic diamide derivatives containing 1,2,3‐triazole moiety were synthesized using one‐pot click chemistry approach and characterized by ¹H NMR and HRMS. The insecticidal activity against armyworm (Mythimna separata), Tetranychu scinnabarinus and cowpea aphid (Aphis craccivora) was evaluated. Compounds 4II‐a and 4II‐i showed 50% insecticidal activity against armyworm (Mythimna separata) at the concentration of 4 mg/L and one‐third of the compounds had moderate activity against Tetranychus cinnabarinus at 500 mg/L.