Synthesis and Antibacterial Activities of 4—Amino—3—（1—aryl—5—methyl—1,2,3—triazol—4—yl）—5—mercapto—1,2,4—triazoles／2—Amino—5—（1—aryl—5—methyl—1,2,3—triazol—4—yl）—1,3,4—

Treatment of 4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoles with benzaldehyde,acetone and ω-bromoacetophenone was tested and compared.The title compounds Schiff bases,amides,imidazolo [2,1-b]-1,3,4-thiadiazoles and 7H-s-triazolo[3,4-b]-1,3,4-thiadiazines have been confirmed by elemental analyses,^1H NMR,IR and MS spectra.All the compounds have also been screened for their antibacterial activities against B.subtilis,S.aureus and E.coli.     

A New Method for Synthesis of Methyl 3—Azido—3—deoxy—2—O—mesyl—5—O—benzoylxylofuranoside

A new method for synthesis of 3-azido-3-deoxyxylofuranoside was described. D-ribose was methylated, then treated with methanesulfonyl chloride to give Ⅱ.Ⅱ was selectively replaced by benzoate at the 5-position to give Ⅲ. All these processes gave good yields. Ⅲ was treated with sodium azide to afford Ⅳ, whose structure was determined by ^1H NMR and ^13C NMR.     

SYNTHESIS AND MOLECULAR STRUCTURE OF METHYL 1—BENZYL—6—PHENYLPIPERIDIN—2—ONE—5—CARBOXYLATE

<正> C20H21NO3,Mr=323.39,monoclinic, space group P21, a= 7. 338(2), b=15. 419(3),c=7. 515(1)A,β=95.98(1)°,V= 845. 7(2)A3,Dm(flotation in aq. KL)=1.267,Dx(Z=2)=1.270gcm-3,λ(MoKα)=0.71069A,μ=0.08cm-1,F(000)=344,T=295°K,final RF=0. 042 for 1651 observed reflections. The title compound was synthesized and established as the trans isomer, with the phenyl and carbomethoxy substituents occupying pseudo-axial and axial positions, respectively, of the piperidin-2-one ring in a half-chair conformation.     

A New Solution—phase Parallel Synthesis of 2—Alkyamino—3—aryl—5—phenylmethylene—3,5—dihydro—4H—imidazol—4—ones

Thirteen new 2-alkylaminoimidazolones(4) wre rapidly synthesized by a new solution-phase parallel synthetic method,which includes aza-Wittig reaction of iminophosphorane(1) with aromatic isocyanate to give carbodi-imide(2) and subsequent reaction of 2 with various aliphatic primary amine in a parallel fashion.The products were confirmed by ^1H NMR,MS,IR and X-ray crystallographic analysis.The unusual selectivity of the cyclization was probably due to the deometry of the guanidine intermediate.     

Synthesis of 3—Biaryl—1—ferrocenyl—2—propene—1—ones

The novel structures of organometallic compounds 3-biaryl-1-ferrocenyl-2-propene-1-ones 5 were synthesized for nonlinear optical chromophores by Suzuki cross-coupling reaction.Their structures were determined with elemental analyses,^1H NMR spectra and ^13C NMR spectra.     

Synthesis of 5—Aryl—1,2—dihydro—1—pyrrolizinones

In order to search for new potent anti-inflammatory and analgesic agents in pyrrolizinones,the title compounds were designed and synthesized.A series of the compounds were prepared with two different synthetic schemes.Some of the compounds showed remarkable anti-inflammatory and/or analgesic activities on mice.     

Crystal and Molecular Structure ofN—（Pyridin—2—yl—carbonyl）—2—ethoxycarbonyl—benzene sulfonamide

1 INTRODUCTION The sulfonylurea herbicides have been well known for their exceptional low dosage, good crop selectivity and low mammalian toxicity. They can block the biosynthesis of branched amino acids by inhibiting ALS enzyme in plants so as to inhibit weeds. Levitt G. divided the structure of sulfonylurea into three parts: (1) aryl group, (2) bridge and (3) heterocycle[1]. Later Ort et al. modified the bridge by omitting moiety NH in the bridge, synthesized N-(substituted pyrimid…     

Polybinaphthyls of （R）—3,3‘—Diiodo—2,2’—binaphtho—20—crown—6 with p—Divinylbenzene via Heck Cross—coupling Reaction

The present paper deals with the polybinaphthyls of (R）-3,3‘-Diiodo-2,2‘-binaphtho-20-crown-6 with p-divinylbenzedne under Heck-coupling reaction condition.Both the monomers and the polymer were analyzed by NMR,FTIR,UV,CD,fluorescent spectroscopy,polarimetry,GPC and elemental analysis.The polymer can emit a strong blue fluorescence and is expected to have the potential application in the polarized bluelight emitting sensors.The chiral conjugated polymer exhibits a strong Cotton effect in its Circular Dichroism (CD-) spectrum,indicating the high rigidity of the polymer backbone.     

Structures of N—（2,3,4,6—Tetra—O—acetyl—β—D—glycosyl） thiocarbamic Benzoyl Hydrazine

The crystal structure of N-(2,3,4,6-tetra-O-acetyl-β-D-gly-cosyl)-thiocarbamic benzoyl hydrazine(C22H27N3O9S) was determined by X-ray diffracton method.The hexopyranosyl ring adopts a chair conformation.All the ring substituents are in the equatorial positions.The acetoxyl-methyl group is in synclinal conformation.The S atom is in synperiplanar conformation while the benzoyl hydrazine moiety is anti-periplanar.The thiocarbamic moiety is almost companar with the benzoyl hydrazine group.There are two intramolecular hydrogen bonds and one intermolecular hydrogen bond for each molecule in the crystal structure.The molecules form a network structure through intermolecular hydrogen bonds.     

Synthesis of Cholest—5—en—24—oxo—3β,19—Diacetate

Cholest-5-en-24-oxo-3β,19-diacetate was synthesized strarting form stigmasterol 3 via seven step reactions in 21.0% overall yield. It can be served as a key intermediate for the synthesis of many biologically active 19-hydroxylated sterols.     

Synthesis and Nonlinear Optical Characterization of a New Twophoton Absorbing Organic Dye：DMAHAS

IntroductionThepotentialforuseoftwo photonabsorbingmoleculesinapplicationsrangingfromopticallimiting1 3tothreedimensional (3D)fluorescencemicroscopy4 and 3Dmicrofabricationandopticaldatastorage5,6 hasstimulatedresearchonthedesign ,synthesis ,andcharacterizationofnewmoleculeswithlargetwo photonabsorptivities .7,8Thetwo photonabsorption (2PA)processconsideredherein volvesthesimultaneousabsorptionoftwophotons ,eitherdegeneratingornondegenerating ,atwavelengthswellbe yondthelinearabsorptionspectr…     

一个新的具有大的吸收截面的双光子引发剂的合成和非线性光学性质

E,E-1,4-Bis（4＇-N,N-diphenylaminostyryl）-2,5-dimethoxybenzene （DPAMOB） has been synthesized by a simple and effective solid phase Wittig reaction and characterized by 1^H NMR spectra and elemental analysis, Linear absorption, single-photon induced fluorescence and two-photon induced fluorescence spectra were experimentally studied. The new dye has a large two-photon absorption （TPA） cross-section of σr= 1007,2 GM [1 GM= 1 × 10^-50 cm^4·s/（photon molecule）] at 800 nm measured by the two-photon induced fluorescence method. The experimental results confirm that DPAMOB is a good TPA chromophore and can successfully initiate two-photon photopolymerization of ethoxylated trimethylolpropane triacrylate esters （SR454）. Finally, a microstructure has been fabricated by use of DPAMOB as initiator.     

Synthesis and Nonlinear Optical Properties of a New A-π-A Two-Photon Compound Utilizing Dibenzothiophene as Center

A new two‐photon material, 3E,6E‐bis(2‐pyrid‐4′‐ylvinyl)dibenzothiophene (BPVDBT), has been firstly synthesized by an efficient Pd‐catalyzed Heck coupling route. The single‐ and two‐photon fluorescence, quantum yields, lifetimes, solvent effects of the chromophore were studied in detail and the compound exhibited solvent‐sensitivity. The fluorescence intensity (I_out) and input excitation intensity (I_in) can fit in well with the quadratic parabolas, which indicates that the up‐converted fluorescence was induced by the two‐photon absorption (TPA). TPA cross‐section of BPVDBT has been measured using the two‐photon‐induced fluorescence method, whose value is 14.24×10^?50 cm⁴·s·photon^?1·molecule^?1 at 750 nm. The experimental results confirm that BPVDBT is a good two‐photon absorbing chromophore with an A‐π‐A type.     

Synthesis,one‐ and two‐photon properties of poly[9,10‐bis(3,4‐bis(2‐ethylhexyl‐oxy)phenyl)‐2,6‐anthracenevinylene‐alt‐N‐octyl‐3,6‐/2,7‐carbazolevinylene]

The synthesis, one‐ and two‐photon absorption (TPA) and emission properties of two novel 2,6‐anthracenevinylene‐based copolymers, poly[9,10‐bis(3,4‐bis(2‐ethylhexyloxy)phenyl)‐2,6‐anthracenevinylene‐alt‐N‐octyl‐3,6‐carbazolevinyl‐ene] ( P1 ) and poly[9,10‐bis(3,4‐bis(2‐ethylhexyloxy)phenyl)‐2,6‐anthracenevinyl‐ene‐alt‐N‐octyl‐2,7‐carbazolevinylene] ( P2 ) were reported. The as‐synthesized polymers have the number‐average molecular weights of 1.56 × 10⁴ for P1 and 1.85 × 10⁴ g mol^?1 for P2 and are readily soluble in common organic solvents. They emit strong bluish‐green one‐ and two‐photon excitation fluorescence in dilute toluene solution (? _P1 = 0.85, ? _P2 = 0.78, λ_em( P1 ) = 491 nm, λ_em( P2 ) = 483 nm). The maximal TPA cross‐sections of P1 and P2 measured by the two‐photon‐induced fluorescence method using femtosecond laser pulses in toluene are 840 and 490 GM per repeating unit, respectively, which are obviously larger than that (210 GM) of poly[9,10‐bis‐(3,4‐bis(2‐ethylhexyloxy) phenyl)‐2,6‐anthracenevinylene], indicating that the poly(2,6‐anthracenevinylene) derivatives with large TPA cross‐sections can be obtained by inserting electron‐donating moieties into the polymer backbone. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 463–470, 2010     

Alternating copolymers of 2,6‐bis(p‐dihexylaminostyryl)anthracene‐9,10‐diyl and N‐octylcarbazole with large two‐photon cross sections

We report the synthesis, thermal, one‐ and two‐photon properties of poly(2,6‐bis(p‐dihexylaminostyryl)anthracene‐9,10‐diyl‐alt‐N‐octylcarbazole‐3,6‐/2,7‐diyl) ( P1/P2 ). The as‐synthesized polymers exhibit number‐average molecular weights of 1.7 × 10⁴ for P1 and 2.1 × 10⁴ g/mol for P2 . They emit strong one‐ and two‐photon excitation fluorescence with the peak around 502 nm, and the fluorescence quantum yields around 0.76 in chloroform. In film state, P1 and P2 show different red‐shift emission with the peaks at 512 nm and 523 nm, respectively. The DSC measurement reveals that as‐synthesized polymers are all amorphous aggregates with the glass transition temperatures of 131 °C for P1 and 152 °C for P2 . The solution two‐photon absorption (TPA) properties of P1 and P2 in chloroform are measured by the two‐photon‐induced fluorescence method using femtosecond laser pulses (120 fs). The TPA cross sections (δ) are measured over the range of 700–900 nm. The maximal δ of P1 and P2 all appear at ～800 nm and are 1010 GM and 940 GM per repeating unit, respectively. This suggests that no notable interactions among structure units that impair their fluorescence and TPA properties, and the polymers with large δ can be obtained by using the high TPA‐active units as building blocks. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

N‐Annulated Perylene‐Substituted and Fused Porphyrin Dimers with Intense Near‐Infrared One‐Photon and Two‐Photon Absorption

Fusion of two N‐annulated perylene (NP) units with a fused porphyrin dimer along the S₀–S₁ electronic transition moment axis has resulted in new near‐infrared (NIR) dyes 1 a / 1 b with very intense absorption (ε>1.3×10⁵ M ^?1 cm^?1) beyond 1250 nm. Both compounds displayed moderate NIR fluorescence with fluorescence quantum yields of 4.4×10^?6 and 6.0×10^?6 for 1 a and 1 b , respectively. The NP‐substituted porphyrin dimers 2 a / 2 b have also been obtained by controlled oxidative coupling and cyclodehydrogenation, and they showed superimposed absorptions of the fused porphyrin dimer and the NP chromophore. The excited‐state dynamics of all of these compounds have been studied by femtosecond transient absorption measurements, which revealed porphyrin dimer‐like behaviour. These new chromophores also exhibited good nonlinear optical susceptibility with large two‐photon absorption cross‐sections in the NIR region due to extended π‐conjugation. Time‐dependent density functional theory calculations have been performed to aid our understanding of their electronic structures and absorption spectra.     

3,4,9,10-Perylenetetracarboxylic Acid Derivatives, Their Spectral Behavior and Their Chemical Interaction with Hydrated Iron Oxide Nanopar

The photophysical properties such as electronic absorption, excitation and emission spectra as well as molar absorptivity and fluorescence quantum yield of N,N‐bis(pyrimidenyl)‐3,4,9,10‐perylenetetracarboxylic diimide (PmPBD), N,N‐bis(pyridenyl)‐3,4,9,10‐perylenetetracarboxylic diimide (PyPBD) and N,N‐bis(4‐methylpyridenyl)‐3,4,9,10‐perylenetetracarboxylic diimide (MPyPBD) have been measured in different solvents. Both electronic absorption and fluorescence spectra are not sensitive to medium polarity, while the fluorescence quantum yield ((_f) is solvent dependent. Perylene derivatives under investigation undergo molecular aggregation to dimmer or larger aggregates in water. Dye solution in dimethylformmaide (DMF) gives laser emission at 565 nm upon pumping with 337.1 nm nitrogen laser pulse. The excitation energy transfer from 7‐dimethylamino‐4‐methylcoumarine (DMC) to PmPBD has been studied to improve the laser emission of PmPBD. The value of energy transfer rate constant (k_ET) and critical transfer distance (R₀) indicate a F?rster type energy transfer mechanism. There is a large interaction between the perylene compounds under investigation and the hydrated nanoparticles in the excited state therefore the fluorescence quenching rate constant of these derivatives by hydrated iron oxide nanoparticles has a large value.     

3,5‐Bis­[4‐(diethyl­amino)­benzyl­idene]‐1‐methyl‐4‐piperidone and 3,5‐bis[4‐(diethyl­amino)­cinnamyl­idene]‐1‐methyl‐4‐piperidone: prospective biophotonic materials

The structures of 3,5‐bis­[4‐(diethyl­amino)­benzyl­idene]‐1‐methyl‐4‐piperidone, C₂₈H₃₇N₃O, (I), and 3,5‐bis­[4‐(diethyl­amino)­cinnamyl­idene]‐1‐methyl‐4‐piperidone, C₃₂H₄₁N₃O, (II), have been characterized. Because of conjugation between donor and acceptor parts, the central heterocycles (including the carbonyl group) in (I) and (II) are flattened and exhibit a `sofa' conformation, with a deviation of the N atom from the planar fragment. The dihedral angles between the planar part of the heterocycle and the two almost flat fragments that include a phenyl ring and bridging atoms are 23.2 (1) and 11.2 (1)° in (I), and 11.8 (1) and 8.7 (2)° in (II). One‐ and two‐photon absorption of light and the fluorescence of (I) and (II) have also been characterized.     

A Highly K+‐Selective Two‐Photon Fluorescent Probe

A highly K⁺‐selective two‐photon fluorescent probe for the in vitro monitoring of physiological K⁺ levels in the range of 1–100 mM is reported. The two‐photon excited fluorescence (TPEF) probe shows a fluorescence enhancement (FE) by a factor of about three in the presence of 160 mM K⁺, independently of one‐photon (OP, 430 nm) or two‐photon (TP, 860 nm) excitation and comparable K⁺‐induced FEs in the presence of competitive Na⁺ ions. The estimated dissociation constant (K_d) values in Na⁺‐free solutions (K_d^OP=(28±5) mM and K_d^TP=(36±6) mM ) and in combined K⁺/Na⁺ solutions (K_d^OP=(38±8) mM and K_d^TP=(46±25) mM ) reflecting the high K⁺/Na⁺ selectivity of the fluorescent probe. The TP absorption cross‐section (σ_2PA) of the TPEF probe+160 mM K⁺ is 26 GM at 860 nm. Therefore, the TPEF probe is a suitable tool for the in vitro determination of K⁺.     

Pyrrolo[3,2‐b]pyrroles—From Unprecedented Solvatofluorochromism to Two‐Photon Absorption

A combined experimental and theoretical study of the two‐photon absorption (2PA) properties of a series of quadrupolar molecules possessing a highly electron‐rich heterocyclic core, pyrrolo[3,2‐b]pyrrole, is presented. In agreement with quantum‐chemical calculations, large 2PA cross‐section values, σ_2PA≈10²–10³ GM (1 GM=10⁵⁰ cm⁴ s photon^?1), are observed at wavelengths of 650–700 nm, which correspond to the two‐photon allowed but one‐photon forbidden transitions. The calculations also predict that increased planarity of this molecule through removal of two N‐substituents leads to further increase in the σ_2PA values. Surprisingly, the most quadrupolar pyrrolo[3,2‐b]pyrrole derivative, containing two 4‐nitrophenyl substituents at positions 2 and 5, demonstrates a very strong solvatofluorochromic effect, with a fluorescence quantum yield as high as 0.96 in cyclohexane, whereas the fluorescence vanishes in DMSO.