A Simple and Efficient Procedure for Synthesis of Optically Active 1,2,4‐Triazolo‐[3,4‐b]‐1,3,4‐Thiadiazole Derivatives Containing l‐Amino Acid Moieties

Some new and optically active 1,2,4‐triazolo thiadiazoles bearing N‐phthaloyl‐l ‐amino acids were synthesized by reaction of 4‐amino‐5‐(3‐ or 4‐)pyridyl‐3‐mercapto‐(4H)‐1,2,4‐triazoles with N‐phthaloyl‐l ‐amino acids in the presence of phosphorus oxychloride. All the newly synthesized compounds were confirmed by IR, ¹H NMR, ¹³C NMR and elemental analysis.     

Investigation of the Reactions of Indole‐2,3‐diones with Biuret: A Novel Approach for the Synthesis of Spiro[indole‐triazines]

Reactions of indole‐2,3‐diones with biuret afforded 1,3‐dihydro‐3‐ureidoformimido‐2H‐indol‐2‐ones and spiro[3H‐indole‐3,2′(1′H )‐(1,3,5)triazine]‐2,4′,6′(1H ,3′H ,5′H )‐triones indicated these to be solvent dependent. The chemical structures of the products were elucidated by their comprehensive spectroscopic (IR, ¹H‐NMR, ¹³C‐NMR, ¹⁹F‐NMR, and Mass) as well as analytical analysis.     

Synthesis and Structural Characterisation of Derivatives of Tricyclo[5.2.1.02,6]Dec‐8‐Ene‐3,5‐Dione with an Expected Antimicrobial Activity

Anhydrides, imides, N‐ethylimides, N‐hydroxyimides and N‐aminoimides of 1,4,5,6‐tetramethyl‐bicyclo[5.2.1.0^2,6]hept‐5‐ene‐2,3‐dicarboxylic acid, 1,4,5,6,7‐pentamethyl‐bicyclo[5.2.1.0^2,6]hept‐5‐ene‐2,3‐dicarboxylic acid and 7‐ethyl‐1,4,5,6‐tetramethyl‐bicyclo[5.2.1.0^2,6]hept‐5‐ene‐2,3‐dicarboxylic acid were obtained. Antimicrobial activity of the newly obtained derivatives was tested against selected Gram‐positive and Gram‐negative bacteria and fungi of the Candida species. The structures of obtained compounds and their antimicrobial activity were compared. Structure of 1b, 2b and 1e were determined by an X‐ray analysis.     

Isolation and spectral study of 4‐methyl‐6,8‐dihydroxy‐7H‐benz[de]anthracen‐7‐one

4‐Methyl‐6,8‐dihydroxy‐7H‐benz[de]anthracen‐7‐one was isolated from the sap of Aloe by column chromatography. Its ¹H and ¹³C NMR spectra were completely assigned by utilizing two‐dimensional ¹H‐detected heteronuclear one‐bond (HMQC) and multiple‐bond (HMBC) chemical shift correlation experiments together with ¹H–¹H COSY and DEPT techniques. These techniques were also valuable in assigning the protons and carbons of those benzanthrone compounds which were previously incompletely reported because of the overlap of proton signals. The molecular structure was elucidated by 2D NMR analysis. The spectral properties (MS, IR and UV) are also presented. Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis and Antimicrobial Activity of Some Condensed [4‐(2,4,6‐Trimethylphenyl)‐1(2H)‐oxo‐phthalazin‐2‐yl]acetic Acid Hydrazide

Some new 1,2,4‐triazolo‐, 1,3,4‐oxadiazolo‐, 1,3,4‐thiadiazol‐, and pyrazolo‐2,4,6‐trimethylphenyl‐1(2H)‐oxo‐phthalazine derivatives were synthesized and identified by IR, ¹H NMR, ¹³C NMR, MS and elemental analysis. The new compounds were synthesized with the objective of studying their antimicrobial activity.     

Unexpected Spiroproducts from the Reaction of N‐Benzoylglycine with Ortho‐Formylbenzoic Acids −3,5′‐Dioxo‐2′‐Phenyl‐1,3‐Dihydrospiro[Indene‐2,4′‐[1,3]Oxazol]‐1‐yl Acetates: Establishments of Their Structure

This paper describes a method of preparation of new 3,5′‐dioxo‐2′‐phenyl‐1,3‐dihydrospiro[indene‐2,4′‐[1,3]oxazol]‐1‐yl acetate and its 5‐chloro‐ and bromoderivatives as products of interaction of N‐benzoylglycine (hippuric acid) with corresponding ortho‐formylbenzoic acids. The reaction carried out in acetic anhydride media in the presence of piperidine as catalyst. The novel spirocompounds were purified by column chromatography from multicomponent reaction mixtures. The composition of the spiro‐products was confirmed by C, H, N element analysis. The structure was established by IR, MS, ¹H‐ and ¹³C‐NMR analysis including COSY ¹H‐¹³C experiments.     

Preparation,Characterization and Non‐isothermal Kinetics of the Dehydration Process of [Sm(p‐MOBA)3bath]2·4H2O

The new complex of [Sm(p‐MOBA)₃bath]₂·4H₂O (p‐MOBA, p‐methoxybenzoate; bath, 4,7‐diphenyl‐1,10‐phenanthroline) was synthesized and characterized by elemental analysis, molar conductance, IR, UV and XRD patterns. The thermal decomposition of the complex was studied under the non‐isothermal condition by TG‐DTG and IR techniques. The most probable mechanism function of the dehydration process was obtained from the analysis of DSC curves of the complex employing the double extrapolated method on the basis of integral isoconversional non‐linear (NL‐INT) and Tang‐Wanjun integral equations. The integral function of the mechanism was [1? (1?α)^1/2]^1/2 and the corresponding kinetic parameters (activation energy E and the pre‐exponential factor A) were obtained.     

A New Megastigmane Palmitate and a New Oleanane Triterpenoid from Aster yomena Makino

A new megastigmane palmitate, 9‐oxomegastigm‐5(13)‐ene‐2β‐palmitate ( 1 ), and a new oleanane triterpenoid, (3β)‐3,23,28‐trihydroxyolean‐12‐en‐11‐one ( 2 ), together with three known oleanane‐type triterpenoids, β‐amyrin ( 3 ), erythrodiol ( 4 ), and (3β)‐olean‐12‐ene‐3,23,28‐triol ( 5 ), were isolated from the aerial parts of Aster yomena (Asteraceae). Their structures were identified based on 1D‐ and 2D‐NMR analysis, including ¹H,¹H‐COSY, HSQC, HMBC, and NOESY techniques.     

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.     

A new two‐dimensional CoII coordination polymer based on bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether and biphenyl‐4,4′‐diyldicarboxylic acid: synthesis,crystal structure and photocatalytic degradation activity

A novel two‐dimensional Co^II coordination framework, namely poly[(μ₂‐biphenyl‐4,4′‐diyldicarboxylato‐κ²O⁴:O^4′){μ₂‐bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether‐κ²N³:N^3′}cobalt(II)], [Co(C₁₄H₈O₄)(C₂₀H₁₈N₄O)]_n, has been prepared and characterized by IR, elemental analysis, thermal analysis and single‐crystal X‐ray diffraction. The crystal structure reveals that the compound has an achiral two‐dimensional layered structure based on opposite‐handed helical chains. In addition, it exhibits significant photocatalytic degradation activity for the degradation of methylene blue.     

Design,Synthesis, and Insecticidal Activity of 1,5‐Diphenyl‐1‐pentanone Analogues

Three series of novel 1,5‐diphenyl‐1‐pentanone derivatives were designed and synthesized. Their structures were characterized by IR, ¹H NMR techniques, and elemental analysis. The insecticidal activities of the new compounds were preliminarily evaluated. The bioassay results indicated that the compounds X11 – X30 displayed better aphicidal activity against Aphis gossypii than compounds X1 – X10 and the lead compound (E)‐1,5‐diphenyl‐1‐penten‐1‐one ( A ). The inhibitory rates of compounds X6 and X29 were 100% against Plutella xylostella (L.) at 600 mg·L^?1. Compounds X12 , X13, X19 , X24, X25 , X26 and X27 showed higher insecticidal activity against Tetranychus cinnabarinus (Boisduval) at 600 mg·L^?1 than the lead compound ( A ).     

Pseudohalide‐directed Assembly of Two Zinc(II) Coordination Polymers with a 3,4‐Bis(3‐pyridyl)‐5‐(4‐pyridyl)‐1,2,4‐triazole Tecton

The zinc(II) pseudohalide complexes {[Zn(L³³⁴)(SCN)₂(H₂O)](H₂O)₂}_n ( 1 ) and [Zn(L³³⁴)(dca)₂]_n ( 2 ) were synthesized and characterized using the ligand 3,4‐bis(3‐pyridyl)‐5‐(4‐pyridyl)‐1,2,4‐triazole (L³³⁴) and ZnCl₂ in presence of thiocyanate (SCN^–) and dicynamide [dca, N(CN)₂^–] respectively. Single‐crystal X‐ray structural analysis revealed that the central Zn^II atoms in both complexes have similar octahedral arrangement. Compound 1 has a 2D sheet structure bridged by bidentate L³³⁴ and double μ_N,S‐thiocyanate anions, whereas complex 2 , incorporating with two monodentate dicynamide anions, displays a two‐dimensional coordination framework bridged by tetradentate L³³⁴ ligand. Structural analysis demonstrated that the influence of pseudohalide anions plays an important role in determining the resultant structure. Both complexes were characterized by IR spectroscopy, microanalysis, and powder X‐ray diffraction techniques. In addition, the solid fluorescence and thermal stability properties of both complexes were investigated.     

Photo‐Fries Rearrangement of Carbazol‐2‐yl Sulfonates: Efficient Tool for the Introduction of Sulfonyl Groups into Polycyclic Aromatic Compounds

Systematic studies on the photo‐Fries rearrangement of different 9H‐carbazol‐2‐yl sulfonates 2 have shown that this type of conversion can be readily used for the preparative‐scale introduction of alkyl‐ or arylsulfonyl groups into polycyclic aromatic compounds under very mild conditions. A series of new 1‐sulfonyl‐ ( 3 ) or 3‐sulfonyl‐9H‐carbazoles ( 4 ) were prepared in medium‐to‐good yields, and characterized by UV/VIS, ¹H‐NMR, and ¹³C‐NMR spectroscopy, as well as by elemental analysis. Effects of irradiation wavelength, solvent polarity, presence or absence of O₂, and photosensitizers were studied in detail.     

Synthesis of Novel Thioglycoside Derivatives Containing Quinazolinone

A series of novel thioglycoside derivatives containing 4(3H)‐quinazolinone was designed and synthesized from 2‐chloromethyl‐quinazolin‐4(3H)‐ones and 1‐thioglycose. Several 2‐chloromethyl‐quinazolin‐4(3H)‐ones were synthesized on refluxing with 2‐(chloroacetylamino)‐benzoic acid and arylamines in acetonitrile. All of the novel compounds were characterized by IR, ¹H NMR spectra and elemental analysis. The structures of compounds 7b, 8b and 8c have been determined by X‐ray diffraction analysis.     

A three‐dimensional supramolecular framework based on the interlinkage of an interpenetrating diamondoid coordination network

In the development of coordination‐driven crystalline materials, O‐ and N‐atom donors from carboxylate and pyridyl‐based ligands are widely used classes of multidentate bridging ligands composed of several terminal coordinating groups linked by either rigid or flexible spacers. The rigidity of the ligands can play a vital role in the determination of the structures formed. A new Cd^II supramolecular compound, namely poly[μ‐adipato‐κ²O ¹:O⁴‐μ‐adipato‐κ⁴O ¹,O ^1′:O ⁴,O^4′‐diaquabis[μ‐1,4‐bis(pyridin‐4‐yl)‐1,3‐butadiene‐κ²N :N ′]dicadmium(II)], [Cd₂(C₆H₈O₄)₂(C₁₄H₁₂N₂)₂(H₂O)₂]_n , (I), has been synthesized by the self‐assembly of Cd(NO₃)₂·4H₂O, adipic acid (hexane‐1,6‐dioic acid; H₂adp) and the dipyridyl ligand 1,4‐bis(pyridin‐4‐yl)buta‐1,3‐diene (1,4‐bpbd) under hydrothermal conditions. Single‐crystal X‐ray diffraction analysis reveals that each Cd^II centre is located in a distorted octahedral coordination environment, coordinated by one water O atom, three carboxylate O atoms from two different adp²⁻ ligands and two N atoms from two different 1,4‐bpbd ligands. The Cd(H₂O) units are interconnected by the μ₂,κ²‐adp²⁻, μ₂,κ⁴‐adp²⁻ and 1,4‐bpbd ligands, which lie across centres of inversion, to give a 6⁶‐ dia network. Large cavities within a single diamondoid network permit the mutual threefold interpenetration of crystallographically equivalent frameworks. Hydrogen‐bonding interactions between the coordinated water molecules and adp²⁻ carboxylate O atoms anchor the interpenetrating networks into a unique three‐dimensional supramolecular structure. Topologically, taking the coordinated water molecules and Cd^II centres as nodes, the whole architecture can be simplified as a binodal (3,7)‐connected supramolecular framework. The identity of (I) was further characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis and powder X‐ray diffraction. The solid‐state photoluminescence properties of (I) were also investigated.     

3-硫代甲酰基中氮茚与三丁基膦的反应

2-Phenyl-3-thioformylindolizine and 1,2-dimethyl-3-thioformylindolizine undergo a novel desulfur coupling reaction in the presence of tributylphosphine to give （E）-1,2-bis（3-indolizinyl）ethenes in high yields. The structures of products were confirmed by IR, ^1H NMR, MS, elemental analysis and single crystal X-ray diffraction analysis. The mechanisms involved in various stages of the reaction were discussed.     

Facile Synthesis,Single‐Crystal Structure,and Biological Evaluation of Novel Pyrazolo[5,1‐d][1,2,5]triazepin‐4‐ones

A facile ring‐enlargement reaction of 2,6‐diphenyl‐4H‐pyrazolo[5,1‐c][1,4]oxazin‐4‐one is described, generating the pyrazolo[5,1‐d][1,2,5]triazepin‐4‐ones in good yields. Structures of the prepared compounds were determined on the basis of IR, ¹H‐ and ¹³C‐NMR, and HR‐MS data. Moreover, the molecular structure was confirmed by the X‐ray crystal‐structure analysis of one compound that was prone to crystallization. Preliminary biological evaluation showed that the compounds 2e – 2h promote the viability and inhibit the apoptosis of vascular endothelial cells at low concentration.     

Cobalt（Ⅱ） Salen Complex with Two Aza-crown Pendants and Its Analogues as Synthetic Oxygen Carriers

Salen with two aza‐crown ether pendants H₂L¹ and its analogues H₂L^2‐H₂L⁴ were successfully synthesized starting from benzo‐10‐aza‐15crown‐5 (BN15C5) or morpholine. Their structures were characterized by IR, MS, ¹H NMR and elemental analysis, and were confirmed by X‐ray diffraction analysis of H₂L¹. Moreover, the saturated oxygen uptake of their cobalt(II) complexes CoL^1‐CoL⁴ in diethyleneglycol dimethyl ether was determined at different temperature. The oxygenation contants (K_O2 ) and thermodynamic parameters (ΔH° and ΔS°) were calculated. The modulation of O₂‐binding capabilities by pendant substituents were investigated as compared with the parent Schiff base complex CoL⁵ (CoSalen). The results indicate that the dioxygen affinities of CoL have been much more enhanced by aza‐crown pendants than that by morpholino pendants, and the O₂‐binding capabilities of CoL¹ and CoL² with aza‐crown pendants would also be enhanced by adding alkali metal cations.     

Synthesis, Crystal Structure, Theoretical Calculation and Thermal Behavior of DNAZ·NTO

DNAZ·NTO was prepared by mixing 3,3‐dinitroazetidine (DNAZ) and 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) in ethanol solution. Single crystals suitable for X‐ray measurement were obtained, which belong to monoclinic, space group P2₁/n with unit cell parameters of a=1.4970(4) nm, b=0.6325(2) nm, c=2.2347(7) nm, β=96.55(1) °, V=2.1022(11) nm³ , D_c=1.752 g·cm^?3, F(000) =1136 and Z=8. Based on the analysis of the molecule structure, the theoretical investigation of the title compound was carried out at B3LYP/6‐311++G** levels, and the natural atomic charge and natural bond orbital analysis were performed. The interaction between the cation and anion was also discussed. The thermal behavior of DNAZ·NTO was carried out by DSC and TG/DTG techniques. The apparent activation energy (E_a) and pre‐exponential constant (A) of the main exothermic decomposition reaction were obtained.     

Construction and photoluminescence properties of a three‐dimensional ZnII coordination network based on naphthalene‐1,4‐dicarboxylic acid and 1,6‐bis(pyridin‐3‐yl)‐1,3,5‐hexatriene

In recent years, coordination polymers constructed from multidentate carboxylate and pyridyl ligands have attracted much attention because these ligands can adopt a rich variety of coordination modes and thus lead to the formation of crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[μ₂‐1,6‐bis(pyridin‐3‐yl)‐1,3,5‐hexatriene‐κ²N:N′](μ₃‐naphthalene‐1,4‐dicarboxylato‐κ⁴O¹,O^1′:O⁴:O^4′)zinc(II)], [Zn(C₁₂H₆O₄)(C₁₆H₁₄N₂)]_n, has been prepared by the self‐assembly of Zn(NO₃)₂·6H₂O, naphthalene‐1,4‐dicarboxylic acid (1,4‐H₂ndc) and 1,6‐bis(pyridin‐3‐yl)‐1,3,5‐hexatriene (3,3′‐bphte) under hydrothermal conditions. The title compound has been structurally characterized by IR spectroscopy, elemental analysis, powder X‐ray diffraction and single‐crystal X‐ray diffraction analysis. Each Zn^II ion is six‐coordinated by four O atoms from three 1,4‐ndc²⁻ ligands and by two N atoms from two 3,3′‐bphte ligands, forming a distorted octahedral ZnO₄N₂ coordination geometry. Pairs of Zn^II ions are linked by 1,4‐ndc²⁻ ligands, leading to the formation of a two‐dimensional square lattice ( sql ) layer extending in the ab plane. In the crystal, adjacent layers are further connected by 3,3′‐bphte bridges, generating a three‐dimensional architecture. From a topological viewpoint, if each dinuclear zinc unit is considered as a 6‐connected node and the 1,4‐ndc²⁻ and 3,3′‐bphte ligands are regarded as linkers, the structure can be simplified as a unique three‐dimensional 6‐connected framework with the point symbol 4⁴6¹⁰8. The thermal stability and solid‐state photoluminescence properties have also been investigated.