The STOBBE Condensation,Part IX. The cyclisation of (E)-3-Methoxycarbonyl-4-(5′-methyl-2′-thienyl)-but-3-enoic acid,and α,β-bis-(5-methyl thenylidene)-succinic anhydride,to benzothiophen derivatives

The condensation of 5-methyl-thiophen-2-aldehyde with dimethyl succinate in the presence of potassium t-butoxide or sodium hydride gave predominantly (E)-3-methoxy-carbonyl-4-(5′-methyl-2′-thienyl)-but-3-enoic acid 1a , whose configuration is proved by cyclisation with sodium acetate in acetic anhydride to the corresponding benzothiophen derivatives 2 . Alcoholysis of the derived (E)-carboxy-4-(5′-methyl-2′-thienyl)-but-3-enoic anhydride 3 gives the half-ester 1c which is isomeric with the half-ester 1a . Condensation also gave the α,β-bis-(5-methyl thenylidene)-succinic acid 4a in small amounts. The derived anhydride 5 yields on pyrolysis 4-(5′methyl-2′-thienyl)-2-methyl-benzothiophen-5,6-dicarboxylic anhydride 6 .     

The STOBBE condensation. XI. The cyclisation of (Z)- and (E)-3-methoxycarbonyl-2-methyl-4-(2′-naphthyl)-4-phenyl-but-3-enoic acids to the corresponding polysubstituted phenanthrene and naphthalene derivatives

(Z)- and (E)-3-methoxycarbonyl-2-methyl-4-(2′-naphthyl)-4-phenyl-but-3-enoic acids 1 a and 4 a have been converted into methyl-4-acetoxy-3-methyl-1-phenylphenanthrene-2-carboxylate 2 a and methyl 4-acetoxy-3-methyl-1-(2′-naphthyl)-2-naphthoate 5 a . The derived phenolic acids 2 b and 5 b are converted to methyl 4-methoxy-3-methyl-1-phenyl-phenanthrene-2-carboxylate 2 c and methyl 4-methoxy-3-methyl-1-(2′-naphthyl)-2-naphthoate 5 c ; which are saponified to the corresponding methoxy acids 2 d and 5 d . Alcoholysis of the anhydrides 3 and 6 gives the corresponding half-esters 1 c and 4 c , respectively.     

2-氯-5-(4-氯-1-甲基-5-三氟甲基-1H-吡唑-3-基)-4-氟苯甲醛的合成

2－氯－5－（4－氯－1－甲基－5－三氟甲基－1H－吡唑－3－基）－4－氟苯甲醛是合成除草剂的中间体，它可以通过以下2步反应制得：首先，4－氯－3－（4－氯－2－氟－5－甲基苯基）－1－甲基－5－三氟甲基－1H－吡唑在乙酸／乙酐混合溶剂中用三氧化铬氧化，然后，在乙醇／水混合溶剂中，用碳酸氢钠催化水解得目的的产物，2步反应总收率达到71．6％。     

Synthesis of some new 3-(2′-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-one derivatives as antimicrobial agents

3-(2′-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one was reacted with acetylacetone, ethyl acetoacetate and diethylmalonate in the presence of sodium ethoxide to afford the alkylation products IV, V and VI , Compounds IV, V and VI were reacted with hydrazine hydrate, phenylhydrazine, hydroxylamine hydrochloride, urea and thiourea to yield 3-(2′-heterocyclicethyl)-2-methyl-3,4-dihydroquinazolin-4-one derivatives VII-XV . The structures of the synthesized compounds were elucidated by elemental analyses and spectroscopic (IR and XH-NMR) analyses. The prepared compounds were tested for their antimicrobial activities in comparison with tetracycline as a reference compound.     

Synthesis of pyrazolo[4′,3′:5,6]pyrazino[2,3-c]pyrazoles and pyrazolo[4′,3′:5,6]pyrazino[2,3-d]pyrimidines and their application to polyester fibres

4-Nitroso-1-phenyl-3-methyl-5-aminopyrazole ( 1 ) was condensed with ethylcyanoacetate ( 2 ), malononitrile ( 4a ) and 2-cyanomethylbenzimidazole ( 4b ) to yield 6-hydroxy-5-cyano, 6-amino-5-cyano and 6-amino-5-(benzimidazol-2-yl)-3-methylpyrazolo [3,4-b]pyrazines 3, 5a and 5b , respectively. 5-Cyano-6-chloro derivative 6 obtained from 3 was converted to 3-aminopyrazolo[4′,3′:5,6]pyrazino[2,3-c]pyrazoles 8a and 8b by the treatment with hydrazin hydrate ( 7a ) and phenylhydrazine ( 7b ), respectively. Compound 5a was treated with formamide ( 9a ), urea ( 9b ) and thiourea ( 9c ) to give 4-aminopyrazolo[4′,3′:5,6]pyrazino[2′3′-d]pyrimidines 10a–10c. With refluxing acetic anhydride compounds 8a, 8b and 10a gave corresponding acetamido derivatives 8c, 8d and 10d. Compound 5a was treated with ethylorthoformate ( 11 ), acetic anhydride ( 12 ) or benzoylchloride ( 13 ) to give fused benzimidazopyrazolo[4′,3′:5,6]pyrazino[2′,3′-d]pyrimidines, viz., benzimidazol[1,2-c]pyrazolo[4,3-g]pteridines ( 14a–14c ). Some of the compounds 8, 10 and 14 were applied to polyester as disperse dyes and their fastness properties were studied.     

Radical Copolymerization of 2-(3′-Acryloxy)propoxythioxanthone and 1-Methyl-4-(3′-acryloxy)propoxythioxanthone with Methyl Methacrylate

Two new monomers based on thioxanthone, 2-(3′-acryloxy)propoxythioxanthone (M-2) and 1-methyl-4-(3′-acryloxy)propoxythioxanthone (M-4), were prepared and their radical copolymerization at 70°C with methyl methacrylate (MMA) was studied. By varying the conversion reached for a fixed feed composition, f_MMA=0·983, and using Jaacks method, the reactivity ratios were determined. Identical values of reactivity ratios were found for both systems, with values of r_MMA=2·46 and r_M-2=r_M-4=0·4. The homopolymerization of MMA in the presence of a model compound, 1-methyl-4-propoxythioxanthone, was also examined and confirmed that the thioxanthone chromophore does not have any influence on the free radical polymerization of MMA. © of SCI.     

Studies on the Vilsmeier-haack reaction. Part XIII: Novel heterocyclo-substituted 4,4′-bi-pyrazolyl dithiocarbamate derivatives

5-Imino-3-methyl-l-phenyl-2-pyrazoline-4-dithiocarbamic acid (I) underwent simultaneous formylation and dimerization reactions with the Vilsmeier reagent giving 4-[5′-imino-3-(1″-formyl-2″-dimethylaminoethenyl)-3′-methyl-1′-phenyl-1′H-pyrazolo-4′-dithiocarbamyl-2,4-dihydro-3-imino-5-methyl-2-phenyl-1-pyrazoline]dithiocarbamate (II) which hydrolysed with sodium hydroxide to give 4-[3′-(1″-formyl-2″-hydroxyethenyl)-3′-methyl-1-phenyl-1′-H-pyrazolo-4′-dithiocarbamyl-1′-pyrazoline]dithiocarbamate-5,5′-dione (IV). Treatment of II and/or IV with morpholine, piperidine, piperazine, hydroxylamine, hydrazine hydrate or phenylhydrazine afforded the corresponding dipyrazolo-4,4′-dithiocarbamate derivatives with different heterocyclic systems at the 3-position. The structures of these compounds were confirmed by microanalysis data, IR and ¹H-NMR spectrometry. All synthesized compounds have been screened in vitro against Gram-positive and Gram-negative bacteria, and fungi.     

Synthesis of 4,4′-aryldihydrazono-3-(3′-pyridyl)-2-pyrazolin-4,5-diones and 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles and their application as disazo disperse dyes. Part II

3-(3′-Pyridyl)-2-pyrazoline-4,5-dione 4,4′(4,4′-biphenylenedihydrazone and p-phenylenedihydrazone) and its derivatives ( IIa-e, IIIa-e ) were obtained by the coupling reaction of tetrazotised benzidine and p-diamonobenzene with 3-(3′-pyridyl)-2-pyrazolin-5-ones ( Ia-e ). Similarly, bis-azo compounds containing pyrazole nucleous as, 1-aryl-3-(3′-pyridyl)-4,4′-arylbisazo-5-aryliminopyrazoles ( VIa-i and VIIa-i ) were prepared by the interaction of the corresponding chloro compound ( IV and V ) with aromatic amines. The compounds so obtained ( II, III, VI and VII ) are used as disazo disperse dyes for dyeing polyester fibres fast yellow-orange shades. Their fastness properties towards washing, rubbing, acid-alkaline perspiration and light were investigated.     

Intermediates of Prostanoid Synthesis. Stereospecific conversion of (+)-5β-hydroxycyclopenten-2-yl-1β-acetic acid γ-lactone into (+)-1β-methoxycarbonylmethyl-2β,3β-(p-nitrobenzylidene)-dioxycyclopentan-5-one

Starting from (+)-5β-hydroxycyclopenten-2-yl-1β-acetic acid γ-lactone ( 1 ), (+)-1β-methoxycarbonylmethyl-2β, 3β-(p-nitrobenzylidene)-dioxycyclopentan-5-one ( 7 ) was prepared within 4 steps. Subsequent cleavage of the latter gives (−)-3β-hydroxy-1-methoxy-carbonylmethylcyclopent-1-en-5-one ( 8a ). Hydroxylation of the lactone ( 1 ) was found to give (+)-2β,3β,5β-trihydroxycyclopentyl-1β-acetic acid γ-lactone ( 2a ) with cis-oriented hydroxy groups in respect to the lactone ring. No formation of the trans-isomer, as has been reported earlier [4], was observed.     

Fluoro Substituted Monomeric and Uni-Dimensional Polymeric Organotin(IV) Esters of (E)-4-oxo-4-((3-trifluoromethyl)phenyl)amino)but-2-enoic acid; Synthesis, Characterization and Their In vitro Inhibitory Studies

Inhibition effects of novel organotin(IV) esters of (E)-4-oxo-4-((3-trifluoromethyl)phenyl)amino)but-2-enoic acid have been studied against bacterial, fungal, tumoral and insecticidal strains. The complexes have shown potency against all these strains and is attributed to the multiple interactive sites of the ligand that not only change the environment around tin but also can make interactions with DNA. The synthesized complexes were characterized by physical, spectral, analytical and multinuclear nmr (¹H, ¹³C, ¹¹⁹Sn) data. The X-ray structure analysis of the complex is reported.     

Trennung der Enantiomeren von (S,R)-1,1′-Bi-2,2′-naphthyl-hydrogenphosphat mittels (1R, 2R)- bzw. (1S,2S)-2-Amino-1-(4-nitrophenyl)-propan-1,3-diol

Resolution of the Enantiomers of (S,R)-1,1′-Bi-2,2′-naphthylhydrogenphosphate by (1R,2R)- and (1S,2S)-2-Amino-1-(4-nitrophenyl)-propane-1,3-diol The resolution of the diastereoisomeric salts of the title compounds was possible in the presence of a ketone, especially acetone, which forms oxazolidines ( 3a–d ) with the chiral bases. These oxazolidines afforded separable salts with the (S,R)-1,1′-Bi-2,2′-naphthylhydrogenphosphate ( 4 ). The structures of these salts were proved by m.s. and n.m.r. spectroscopy.     

Ermüdungsprodukte des photochromen 2-(2′,4′-Dinitrobenzyl)-pyridins

Fatigue Products of Photochromic 2-(2′,4′-Dinitrobenzyl)-pyridine Under prolonged irradiation or frequent repetitions of its photochromic cycle, 2-(2′,4′-dinitrobenzyl)-pyridine 1 shows fatigue phenomena both in solid state and in solution. These phenomens — yellow discoloration, depression of the melting point, decrease of band intensity of the coloured form, shorter lifetime of the coloured form — are caused by irreversible redox processes and subsequent reactions at the methylene and ortho-nitro groups which are essential for photochromism. Azomethine 2 , ketone 3 and amine 4 are isolated as the major fatigue products.     

Competitive interaction of polyanions and 2-(4′-hydroxyphenylazo) benzoic acid with bovine serum albumin

The binding of the anionic dye 2-(4′-hydroxyphenylazo) benzoic acid (HABA) to bovine serum albumin (BSA) at pH 6.0–7.5 was studied by spectrophotometry. The values of the dissociation constants were obtained by use of a modified Langmuirtype equation for HABA. Competitive binding of the polyanions sodium poly(styrene sulfonate) (PSSNa), potassium poly(vinyl sulfate) (PVSK), poly(acrylic acid) (PAA), and poly(methacrylic acid) (PMAA), with HABA to BSA were evaluated by variations in the difference spectra of BSA-HABA-polymer systems.     

Anodic oxidations—I. The Kolbe oxidation of unsymmetrical half-esters derived from stobbe condensation

The Kolbe oxidation of some partially neutralized half-ester, viz., 3-carbethoxy-4,4-diphenyl but-3-enoic acid ($\text{1}$), 3-carbethoxy-4,4-dimethyl but-3-enoic acid ($\text{2}$), 3-carbethoxy-3-cyclopent-1′-en-propionic acid ($\text{3}$) and 3-carbethoxy-3-cyclohex-1′-en-propionic acid ($\text{4}$), has been investigated in an undivided cell at smooth platinum foil anode in methanol. In order to optimize the yield of the dimer, the anodic oxidation of $\text{1}$ has been studied in detail by varying different parameters, like current density, degree of partial neutralization of the half-ester and electrode material. Besides the dimerized product, affoded by all these half-ester, two stereoisometric ethers, viz., ethyl 2-methoxymethyl-3,3-diphenyl prop-2-enoate ($\text{1b}$) and ethyl 2-[methoxy (diphenyl)] methyl prop-2-enoate ($\text{1c}$) have been isolated in 69% and 11% respectively from $\text{1}$ in a typical experiment. The probable mechanism for the process has been presented.     

3,1′-Bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl] pyrylium and 1-Benzopyrylium Dyes – Synthesis and Vis/NIR Absorption/Emission Behaviour

A series of new 3,1′-bridged 2-[2′-(4″-dialkylaminophenyl)ethenyl]-4,6-diarylpyrylium perchlorates ( 3 ), 2-[2′-(4″-dialkylaminophenyl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 5–8 , 2-[4′-(4″-dialkylaminophenyl)butadien-1′,3″-yl]-, and 2-[2′-(7″-diethylaminocoumar-3″-yl)ethenyl]-7-diethylamino-1-benzopyrylium perchlorates 10–12 were synthesized and characterized by means of elemental analysis, m.p., Vis/NIR, and ¹H NMR spectra. Semiempirical MO calculations were performed to elucidate the essential features of the chromophores. The size of the bridging ring strongly affects the geometry of the chromophores which, in turn, determines the extent of charge transfer of the longest wavelength electronic transition. Increasing deviation from planarity causes the polymethine-like chromophore to become more polyene-like.     

O- und N-alkylsubstituierte 2-(2′-Hydroxyphenyl)-benzimidazole und -1,3,4-oxadiazole als Komplexbildner und Extraktionsmittel für Kupfer-II-ionen

O- and N-Alkylsubstituted 2-(2′-Hydroxyphenyl)-benzimidazoles and -1,3,4-Oxadiazoles as Complexing and Extracting Agents for Copper-II-Ions 2-(2′-Alkoxyphenyl)-benzimidazoles 1 , 1-alkyl-2-(2′-hydroxyphenyl)-benzimidazoles 2 , 2-(2′hydroxy-4′-alkoxyphenyl)-benzimidazoles 3 , 2-(2′,4′-dialkoxyphenyl)-benzimidazoles 4 and 1-alkyl-2-(2′-hydroxy-5′-nitrophenyl)-benzimidazoles 7 are synthesized by condensation of 2-hydroxybenzoic acid derivatives and o-phenylenediamine or its derivatives. Alkyl chains C₄, C₈ or C₁₂ are introduced by alkylation before or after the ring closure in order to increase the solubility of the reagent in toluene or n-octane. Furthermore the extraction properties of the benzimidazoles are investigated. Also some new analogous compounds of the benzothiazole and the 1,3,4-oxadiazole series were synthesized.     

Direct synthesis of poly(4′‐oxy‐4‐biphenylcarbonyl) and poly(2‐oxy‐6‐naphthoyl) under nonstoichiometric conditions

Direct synthesis of poly(4′‐oxy‐4‐biphenylcarbonyl) (POBP) and poly(2‐oxy‐6‐naphthoyl) (PON) was examined by polycondensation of 4′‐hydroxy‐4‐biphenylcarboxylic acid (HBPA) and 2‐hydroxy‐6‐naphthoic acid (HNA) in the presence of 4‐ethoxybenzoic anhydride or 2‐naphthoic anhydride as condensation reagents. Polymerizations were carried out at 320 °C in aromatic solvents and liquid paraffin. POBP, having a number‐average degree of polymerization (DPn) of 38, was obtained as plate‐like crystals at the molar ratio of HBPA and anhydride of 50 mol%. PON was also obtained as plate‐like crystals but the DPn was only 13. HBPA and HNA were first converted to reactive acyloxyaromatic acid intermediates. Then the DPn was increased by means of reaction‐induced crystallization of oligomers and subsequent solid‐state polymerization via an acid–ester exchange under nonstoichiometric conditions caused by the monocarboxylic acid by‐product. Even though the DPn of PON was not as high, direct polycondensation of HBPA and HNA proceeded successfully with aromatic anhydrides. Copyright © 2004 Society of Chemical Industry     

Substituierte N,N′-Bis(thiazol-2-yl)-diaminoalkane aus α-Thiocyanato-acetophenonen und N,N′-Dialkyl-diamino-alkanen

Substituted N,N′-Bis(thiazol-2-yl)-diaminoalkanes from α-Thiocyanato-acetophenones and N,N′-Dialkyl-diaminoalkanes α-Thiocyanato-acetophenones 1 react with N,N′-dialkyl-diaminoalkanes 2 in the presence of an appropriate weak acid (acetic acid, propionic acid, benzoic acid) to give the hitherto unknown N,N′-dialkyl-N,N′-bis(4-aryl-thiazol-2-yl)-diaminoalkanes 3 . As reaction medium aliphatic alcohols (ethanol, methanol), halogenated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride) or dipolar-aprotic solvents (acetonitrile, dimethylformamide) can be used. - I.r., u.v., n.m.r. and mass spectroscopic data of the novel bisthiazoles 3 are reported.     

Die Reaktion von α,β-Dihalogen-propionitrilen mit monosubstituierten Hydrazinen - einfache Synthese 1-substituierter 3- bzw. 5-Amino-pyrazole

The Reaction of α,β-Dihalogeno-propionitriles with Monosubstituted Hydrazines — A Simple Synthesis of 1-Substituted 3- or 5-Amino-pyrazoles In methanol hydrazines 3 , and α,β-dihalogeno-propionitriles 1, 2 even at 0°C irreversibly yield 3 · HX, and α-halogenoacrylonitriles 4, 5 (A₁). Fast addition of alkyl- and aralkyl- hydrazines 3 to 4, 5 (C) gives 1-substituted 1-(2′-halogeno-2′-cyan-ethyl)-hydrazines 6 , the addition of arylhydrazines 3 to 4, 5 (D) 1-aryl-2-(2′-halogeno-2′-cyan-ethyl)-hydrazines 8 . In methanol 6 spontaneously cyclise (E) to hydrogen halides 7 · HX of 1-alkyl- and 1-aralkyl-3-amino-pyrazoles, 8 with 2 moles of acids (F) to salts 10 · 2HY of 1-aryl-4-halogeno-5-imino-pyrazolidines, and the free 10 spontaneously (G) to hydrogen halides 9 · HX of 1-aryl-5-amino-pyrazoles. Mechanisms (A₁), (C), (D), (E), (F), and (G) are proved by t.l.c., ¹H-n.m.r., and isolation of intermediates, the structures of 7 resp. 9 , using the significant ¹H-n.m.r.-parameter Δ. Simple general syntheses are described for 3-amino-pyrazoles 7 (R = H, alkyl, aralkyl) or 5-amino-pyrazoles 9 (R = aryl) starting with α,β-dihalogeno-propionitriles 1, 2 , and for α-bromo-acrylonitrile 5 .     

1-(5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基-1H-吡唑-3-基)-3-(吡啶-3-基甲基)脲的合成

以5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基-1H-吡唑-3-甲酸与二氯亚砜为起始原料,经酰氯化反应、酰胺反应、霍夫曼重排以及水解反应生成中间体5-(4-氯苯基)-1-(2,4-二氯苯基)-3-氨基-4-甲基-1H-吡唑,再经过与氯甲酸苯酯反应、胺酯交换反应得到标题化合物,其结构经1HNMR、MS谱确证,总收率26.9%。