Studies on condensed heterocyclic compounds II.Synthesis and antibacterial activity of 3-(4''''-pyridyl)-6-aroylamino/arylamino-S-triazolo[3,4-b]-1,3,4-thiadiazoles

3-(4′-Pyridyl)-4-amino-5-mercapto-1,2,4-triazole(1)reacted with aroyl isothiocyanates2a-1 to yield twelve novel 3-(4′-pyridyl)-6-aroylamino-S-triazolo[3,4-b]-1,3,4-thiadiazoles,4a-1.Triethylamine was necessary for the condensation of 1 with phenyl isothiocyanate(3)to give 3-(4′-pyridyl)-6-phenylamino-S-triazolo[3,4-b]-1,3,4-thiadiazole(6).The structures were confirmed bythe elemental and spectral analyses.Their antibacterial activity against B.Subtilis,E.Coli,E.aerogenes and S.aureus was observed preliminary.     

由邻苯二胺合成苯并咪唑、喹喔啉以及1-H-2,3－二氢1,5-苯并氮杂卓

A series of benzo-fused heteroaromatic compounds with 5-, 6- and 7-membered tings, such as benzimidazole,quinoxaline and 1H-1,5-benzodiazepine derivatives, were synthesized through condensation reaction of o-pheny1-enediamine with ary1 aldehydes or ketones. The experimental conditions were carefully examined, and the products were characterized by ^1H NMR, ^13C NMR, MS, IR and elemental analyses. In addition, the structure of a benzodiazaepine derivative with 7-membered ring was confirmed by single crystal X-ray diffraction analysis.     

Synthesis,spectroscopic properties and applications of novel N-heterocycle-containing benzotriazoles as UV absorbers

Two novel iV-heterocycle-containing benzotriazole compounds,5-(5-chloro-2-benzotriazolyl)-6-hydroxy-l,4-dimethyl-3-car-bonitrile -2-pyridone(2) and 4-(5-chloro-2-benzotriazoIyl)-5-methyl-2-phenyl-3-pyrazolone(4),were synthesized from reactant 4- chloro-2-nitroaniline via diazotization,azo coupling,reductive cyclization and acidification.Their structures were confirmed by FT-IR,~1H NMR,mass spectroscopy and elemental analysis.Their spectral properties were investigated and compared with that of a common commercial benzotriazole UV absorber Tinuvin 326.It is found that the novel Af-heterocycle-containing benzotriazole compounds exhibit sharp single peak in the range of 280-400 nm and have much higher molar extinction coefficients than that of Tinuvin 326.Their anti-UV protection properties on polyester fabric were also evaluated and compound 4 was much superior to compound 2 due to its higher exhaustion.     

STUDY ON THE SYNTHESIS OF POLYPERFLUOROTRIAZINE——The Synthesis and Polymerization of a Novel α,ω-Diiodoperfluorooxaalkyl s-Triazine Monomer*

In order to investigate synthetic route of polyperfluorotriazine elastomer, 2-trifluoromethyl4,6-bis(4′-iodo-2′-oxahexafluorobutyl)-1,3,5-triazine (1), a novel triazine monomer, was synthesized from 5-iodo-3-oxa-octafluoropentanesulfonyl fluoride (2) in eight-steps. 2 was reduced by potassium sulfite to the sulfinate (3), which was treated with hydriodic acid to yield 5-iodo-3oxa-hexafluoropentanoic acid (4). Compound 4 was transformed to 5-iodo-3-oxa-hexafluoropentanenitrile (7) through the corresponding ester 5 and amide 6. The desired product 1 was prepared by acylation-cyclodehydration of the imidoylamidine 9, obtained by condensation of the nitrile 7 with the amidine 8.The various methods for the esterification of perfluorocarboxylic acid were studied and a possible mechanism for the transformation of perfluorosulfinate to the corresponding perfluorocarboxylic acid by hydriodic acid was proposed.Crude 1 contained compounds 6, 11, 13, as impurities which were removed by low temperature crystallization followed by filtration through a short alumina column. The monomer 1 was polymerized by UV-irradiation in the presence of Hg with or without solvent. Polyperfluorooxaalkyl triazine 17 thus obtained showed good thermal stability. In the main chain of the polymer there was no weak unit of the uncyclized ring. Polymer 17 had an average molecular weight of ca. 1.33—2.0×10~4 (D. P.=27—42) and the temperature of 10% weight loss in nitrogen was 340℃.     

Synthesis, Characterization, Spectroscopic and Electrochemical Properties of New Mono- and Binuclear Copper（Ⅰ） Complexes with Substituted 2,2′-Bipyridine

The mono- and binuclear Cu(Ⅰ) complexes with substituted 2,2′-bipyridine and iodide ligands, [CuL2]BF4(L=4-methoxycarbonyl-6-(4-methylphenyl)-2,2′-bipyridine (a), 6-(4-hydroxymethylphenyl)-2,2′-bipyridine (b) and 6-(4-methoxylphenyl)-2,2′-bipyridine (c)) and [Cu2(μ-I)2L2] were prepared, and the crystal structures of the complexes were obtained from signal-crystal X-ray diffractional analysis. The spectroscopic properties of the complexes in dichloromethane are dominated by low energy MLCT bands from 360 to 650 nrn. The electrochemical studies of mononuclear complexes reveal that the complexes have stable copper(Ⅰ) state.     

Design,synthesis and systematic evaluation of all possible cyclic dinucleotides (CDNs) that activate human stimulator of interferon genes (STING) variants

Cyclic dinucleotides(CDNs) are known to activate stimulator of interferon genes(STING) and induce type I interferon responses, therefor possess great potentials to be of immunotherapeutic value for cancers and infectious diseases. However, the existence of different single nucleotide polymorphism(SNP) of human STING(hSTING) gene poses an obstacle to achieve broad-spectrum activation by CDNs. We reported here the design and synthesis of a total of 36 CDNs, representing all structural variations, that contain four bases(A, G, C, U) and two linkage directions(2′-5′-linked and 3′-5′-linked phosphodiester).Through systematic evaluation of IFN-β induction with a dual-luciferase reporter assay, we discovered that wild type hSTING and two isoforms(HAQ and AQ) showed strong response while hSTING-R232 H and R293 Q exhibited the relatively weak response to CDNs stimulation. For the first time, we found that the c[G(2′,5′)U(2′,5′)] showed excellent activity against all five hSTING variants even equivalent to the endogenous ligand c[G(2′,5′)A(3′,5′)]. Furthermore, we have also demonstrated that 3′-3′CDNs with two 3′-5′ phosphodiesters showed higher serum and hydrolase stability than 2′-2′ CDNs with two 2′-5′ phosphodiesters and 2′-3′ CDNs with one 2′-5′ and one 3′-5′ phosphodiester. It is very interesting to note that 2′-2′ CDNs has been found for the first time to show strong activity. These findings will stimulate our exploration for the new functional role of CDNs, and provide guidelines to design CDNs based hSTING targeted drugs.     

Synthesis and Biological Activity of Novel Spin Labeled Derivatives of 4′-Demethyl-4-deoxypodophyllotoxin

Seven novel spin labeled derivatives of 4′-demethyl-4-deoxypodophyllotoxin with nitroxyl radicals(TMHPO and TMPRO) were prepared and their cytotoxic and antioxidative activities were tested. Their cytotoxic activities were tested against two tumor cell lines(A-549 and HL-60) in vitro. Among them, five compounds show higher inhibition activity against A-549 cells compared with the clinical drug VP-16(2) and parent compound 4′-demethyl-4-deoxypodophyllotoxin(DDPT, 6). Compounds 8, 10 and 13 show excellent inhibition activity against HL-60 cells. Furthermore, the antioxidative activities of them were tested. All the seven spin labeled compounds show stronger antioxidative activity compared with VP-16(2) and DDPT(6). The partition coefficients P of these derivatives were determined.     

A two step facile synthesis of new steroidal linear and angular pyranones having anti-mycobacterial activity

Title compounds 2′,2′-dimethylcholesta-2,4-dien[3,2-b]-pyran-4′-one(3),2′,2′-dimethyl-3β-substituted cholesta-4,6-dien[7,6- b]-pyran-4′-one(6a,b)and(6c)were prepared by the cyclization of 2-acetylcholesta-2,4-dien-3-ol(2),6-acetyl-3β-substituted- cholesta-4,6-dien-7-ol(5a,b)and(5c)respectively,with pyrrolidine,dry benzene and dry acetone using Dean Stark separator through conventional heating.Furthermore,compounds were also found to be active against Mycobacterium tuberculosis.     

SYNTHESIS OF MAIN CHAIN LIQUID CRYSTALLINE COPOLYESTERS WITH X-SHAPED TWO-DIMENSIONAL MESOGENIC UNIT AND CROWN ETHER CYCLE

A novel series of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4′-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 was prepared via solution condensation polymerization from 4,4′-(α,ω-hexanedioyloxy) dibenzoyl dichloride (M1), 2,5-bis(p-octyloxybenzoyloxy) hydro-quinone (M2) and cis-4,4′-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 (M3). Monomer M1 was synthesized by esterification and substitution of adipoyl chloride with p-hydroxybenzoic acid, monomer M2 was synthesized by esterfication and reduction reaction of 2,5-dihydroxybenzoquinone and p-octanoxybenzoyl chloride and monomer M3 was synthesized by diazotization and coupling reaction of cis-diaminodibenzo-18-crown-6 with phenol. The molecular weights of copolyesters are not high,and the intrinsic viscosity [η] of copolyesters ranges from 0.25-0.35. The monomers' structures were identified by using elemental analysis, IR, UV, 1H-NMR, MS, etc. All the copolyesters are yellowish powders and insoluble in THF and CHCl3 at room temperature except CP9. The properties of copolyesters were investigated by using GPC, [η] , DSC, TG,WAXD and POM. It was found that all the copolyesters entered into liquid crystal phase when they were heated to above their melting temperature (Tm). The typical smectic and nematic phase texture can be observed on POM. Their mesophase transition temperature and thermal stability change regularly with varying the content of cis-4,4′-bis(4-hydroxyphenylazo)dibenzo-18-crown-6 unit in the copolyesters.     

CROSS-LINKING OF AROMATIC POLY（THIOETHER）S

A novel cross-linking process using two high molecular weight aromatic poly(thioether)s,which were synthesized by the reactions of 4,4′-thiobisbenzenethiol with 4,4′-difluorobenzophenone and 4,4′-difluorodiphenylsulfone,respectively, and commercially available lower molecular weight poly(p-phenylene sulfide)was investigated.These reactions were carried out in bulk by the addition of silver tetrafluroborate andα,α′-dibromo-p-xylene at 190℃over a period of 45 min. Furthermore,the same procedure could be modified to cross-link compression-molded films of these three polymers.The thermal and solubility behaviors of these polymers before and after cross-linking reactions,are presented.     

Synthesis of spiro-cyclopropane derivatives containing multiple chiral centers

Tandem asymmetric double Michael addition/internal nucleophilic substitution of the novel chiral source, 5-(l-menthyloxy)-3-bromo-2(5H)-furanone with nucleophilic alcohol compounds has been investigated. The tandem asymmetric reaction can afford four new stereogenic centers with one reaction and give optically pure spiro-cyclopropane derivatives 5a--5d which are difficult to obtain by routine methods. The synthetic method for 5a--5d was studied in detail and the new compounds were identified on the basis of their analytical data and spectroscopic data, such as [α]~(20),IR,~1H NMR,~(13)C NMR, MS and elementary analysis. The absolute configuration of the sprio [5-l-menthyloxy-3-bromo butyrolactocyclopropane-3″, 3′(4′-methyloxy-5′-menthyloxybutyrolactone)] (5a) was established by X-ray crystallography. The work can provide important synthetic strategy in synthesis of some new optically active spiro-cyclopropane analogues and some biologically active molecules with complex structure.     

Synthesis and characterization of novel optically active poly(amide-imide)s and poly(ester-imide)s containing calix[4]arene and amino acid units with binding ability towards alkali metal and toxic heavy metal cations

<正>A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene.The optically active monomers were synthesized by dehydration of L-leucine(and L-isoleucine) and 3,3',4,4'-benzophenonetetracarboxylic- 3,3',4,4'-dianhydride(3) followed by reaction with thionyl chloride to form 5a and 5b.Two methods,polymerization under microwave irradiation and solution polymerization in CH_2Cl_2/TEA,were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b,respectively.The polymerization conditions affected the kind of resulting polymers,poly(amide-imide)s(PAIs) 6a and 6b and poly(ester-imide)s(PEIs) 6a' and 6b' were obtained selectively in good yields and moderate inherent viscosities.Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver,alkali metal and toxic heavy metal cations.Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.     

分子氧条件下Co-ETS-10和Co-AM-6催化苯乙烯氧化生成氧化苯乙烯和苯甲醛（英文）

Pristine ETS-10 and AM-6 and their Co2+-exchanged forms were prepared, and their catalytic activities toward the oxidation of styrene in oxygen atmosphere were studied in dimethylformamide. The catalysts were denoted as Co-E10-n(n = 0, 9, 26, 68, 81) and Co-A6-m(m = 0, 8, 23, 63, 79), where n and m denote the degree of Co2+ exchange. The products of the oxidation process were identified as styrene epoxide(E) and benzaldehyde(B). Both the pristine forms, ETS-10(Co-E10-0) and AM-6(Co-A6-0), and Co2+-exchanged forms displayed catalytic activities. With increasing n or m, the conversion, and hence the rate, increased. Specifically, the rates varied from 6.1 to 12.5 mmol·g-1·h-1with increasing n(Co-E10-n catalysts) and from 5.4 to 12.4 mmol·g-1·h-1 with increasing m(Co-A6-m catalysts). In contrast, the E/B ratio decreased with increasing n or m. More specifically,the E/B ratio decreased from 2.1 to 0.1 with increasing n from 0 to 81(Co-E10-n catalysts) and from 1.3 to 0.1 with increasing m from 0 to 79(Co-A6-m catalysts). Co-E10-9 displayed the highest E yield and Co-A6-79 generated the highest B yield. The highest turnover frequency obtained was 36.3 Co-1·h-1, which was the highest one obtained among those obtained for the Co2+-exchanged zeolites and mesoporous silica reference materials studied in this work.     

Co-ETS-10 and Co-AM-6 as active catalysts for the oxidation of styrene to styrene oxide and benzaldehyde using molecular oxygen

Pristine ETS-10 and AM-6 and their Co2+-exchanged forms were prepared, and their catalytic activi-ties toward the oxidation of styrene in oxygen atmosphere were studied in dimethylformamide. The catalysts were denoted as Co-E10-n (n=0, 9, 26, 68, 81) and Co-A6-m (m=0, 8, 23, 63, 79), where n and m denote the degree of Co2+exchange. The products of the oxidation process were identified as styrene epoxide (E) and benzaldehyde (B). Both the pristine forms, ETS-10 (Co-E10-0) and AM-6 (Co-A6-0), and Co2+-exchanged forms displayed catalytic activities. With increasing n or m, the con-version, and hence the rate, increased. Specifically, the rates varied from 6.1 to 12.5 mmol·g?1·h?1 with increasing n (Co-E10-n catalysts) and from 5.4 to 12.4 mmol·g?1·h?1 with increasing m (Co-A6-m catalysts). In contrast, the E/B ratio decreased with increasing n or m. More specifically, the E/B ratio decreased from 2.1 to 0.1 with increasing n from 0 to 81 (Co-E10-n catalysts) and from 1.3 to 0.1 with increasing m from 0 to 79 (Co-A6-m catalysts). Co-E10-9 displayed the highest E yield and Co-A6-79 generated the highest B yield. The highest turnover frequency obtained was 36.3 Co?1·h?1, which was the highest one obtained among those obtained for the Co2+-exchanged zeolites and mesoporous silica reference materials studied in this work.     

Preparation and Properties of Poly(aryl ether sulfone ketone) Ultrafiltration Membrane Containing Fluorene Group for High Temperature Condensed Water Treatment

Novel poly(aryl ether sulfone ketone)s(PAESK) were synthesized from bisphenol A(BPA),9,9′-bis(4-hydroxyphenyl)fluorene(BHPF),4,4′-dichlorodiphenylsulfone(DCS) and 4,4′-difluorobenzophenone(DFB) via nucleophilic substitution polymerization,which were subsequently used to fabricate ultrafiltration membrane by phase-inversion method for high temperature condensed water treatment.The obtained high molecular weight co-polymers with fluorene group with good solubility and good thermal stability,can be easily cast into flexible,white and non-transparent flat films.The influence of molar ratio of BPA and BHPF on the properties of the prepared co-polymers and membranes was investigated in detail.SEM study of the morphology of the membranes indicated that the prepared membranes possessed homogeneous pores on the top surface and were sponge-like or finger-like in cross-section.Pure water flux of the membranes increased from 71.87 L·m~(-2)·h~(-1) to 247.65 L·m~(-2)·h~(-1),while the retention of BSA decreased slightly,and the water contact angle decreased from 82.1° to 55.6° with the PVP concentration from 0 wt% to 10 wt%.With increasing concentration of PVP,the mechanical properties of membranes decreased,while the thermal stability increased.The permeate flux measurement showed that the PAESK membrane had the potential for high temperature condensed water treatment.     

Determination of 14 whitening active components in cosmetics by ultra-high performance liquid chromatography-triple quadrupole mass spectrometryEI北大核心CSCD

A method based on ultra high performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/ MS) was developed for the analysis of 14 whitening active components in oilycosmetics. The 14 whitening active components were extracted from cosmetics by supersonic extraction with 20 mmol / L potassium dihydrogen phosphate solution, purified by HLB solid phase extraction column and filtered with 0. 22 μm filter membrane. Shim-pack GIST C18 AQ chromatographic column was used for the separation of the whitening active components. Methanol-0. 1% formic acid solution(containing 5 mmol / L ammonium acetate)was employed as mobile phase for gradient elution, and the analytes were detected by electrospray ionization source with positive and negative ion alternate scanning mode and multiple reaction monitoring mode (MRM). The results showed that an effective separation was achieved within 10 min under the optimized conditions, 14 whitening active components exhibited good linear relationships in the respective linear range with the correlation coefficient more than 0. 999. The limits of detection were in the range of 0. 15-2. 5 mg / kg, and the limits of quantitation were in the range of 0. 5-7. 5 mg / kg. The recoveries were from 70% to 117%, and the relative standard deviations were between 0. 2% and 12% . © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

A Novel Diamine, 4′-Phenylphenyl 4-(3′′, 5′′-Diaminobenzoyloxy)- benzoate and Longer Side-chain Polyimide

In our previous study,the polyimides with the side-chain were obtained from3,5-diaminobenzoic-4′-biphenyl ester(DABBE)1.This kind of polyimide films showed some interesting properties,such as excellent solubility,lower density,and higher tensile strength.To understand the influence of various mesogenic units,making reference to those synthesis of polyimides with side-chain2-3,in this study,a novel diamine with higher length/diameter(L/D)ratio containing aryl ester group and biphenyl unit wa…     

New π-conjugated cyanostilbene derivatives:Synthesis,characterization and aggregation-induced emission

Two novel π-conjugated cyanostilbene derivatives,FLU-CNPH and TPE-CNPH,were designed and synthesized by introducing the strong electron donor 1,4-dihydropyrro[3,2-b]indole and AIE electron donor tetraphenylethylene(TPE)to the(3',5'-bis(trifluoromethyl)-biphenyl-4-yl)-acetonitrile,respectively.Both of them were fully characterized and their AIE behaviors were investigated using fluorescence spectroscopy and FE-SEM images.Their optimized structures and frontier molecular orbitals were calculated with the DFT by using Materials Studio 7.0 software to study the relationship between the structure and properties.     

Synthesis of Tetrahydropyridinyltriazolothiadiazines as Possible Muscarinic Agonists

4-Amino-5-(pyridin-3-yl)-4H-l,2,4-triazole-3-thiol 1 were condensed with 2-bromo-l-(substituted phenyl)ethanone to give pyridinyltriazolothiadiazines 2a-c, which were quaternarized with methyl iodide and oxidized with 30 % hydrogen peroxide to afford the corresponding methyl pyridinium salts 3a-c and pyridine- 1 -oxides 4a-c, respectively. The redtiction of compounds 3 and 4 with NaBH4 in methanol produced the target compounds 1-methyl- 1.2.5.6-tetrahydropyridin-3-yl)-6-aryl-s-triazolothiadiazines 5a-c and 3-( l-hydroxyl- 1, 2, 5, 6-tetrahydropyridin -3-yl)-6-aryl-s-triazolothiadiazines 6a-c, respectively. The endothelium vascular relaxing activity of the target compounds was screened.     

Synthesis of Two Novel Rhenium（I） Bipyridyl Photosensitive Dyes

Two novel rhenium(I) 2, 2′-bipyridyl complexes, [(4,4′-di-COOEt-bipy) Re(CO)3 (NCCH3)PF6] and [(4,4′-di-COOEt-bipy) Re (CO)3 (NCS)], a model complex [(4,4′-di-COOEt-bipy) Re (CO)3 (pyridine)PF6], were synthesized. Their ground state electronic spectra and emission spectra were measured in acetonitrile. The MLCT absorption maximum of the complex exhibited a considerable red shift as the ligand changed from pyridine to CNCH3, or SCN.