Oxamic acid derivaties in heterocyclic synthesis: Preparation of 1,2,4-triazolo[1,5-a]pyrazine derivatives

N-Aryl-N-(α-phenylphenacyl)oxamoyl chlorides react with N³-arylsubstituted amidrazones to give functionalized 1,2,4-triazoles which undergo ring-closure by the action of thionyl chloride to give 1,2,4-triazolo[1,5-a]-pyrazinium chlorides in excellent yields.     

The Action of Carbon Disulfide and Sulfur on Enamines,Ketimines, and CH Acids

The reaction of sulfur, carbon disulfide, and enamines at room temperature leads mainly or exclusively to 3H-1,2-dithiole-3-thiones; these are occasionally accompanied by 2H-1,3-dithiole-2-thiones, which can also be prepared by a modified procedure. Many enamines react with sulfur at room temperature to form thioamides. At about 50°C, enamines of acetophenone give 2-benzylidene-4-phenyl-2H-1,3-dithiol. The action of isothiocyanates and sulfur on enamines leads to the formation of thiazolidine-2-thiones. 2H-Thiopyran-2-thiones can be prepaAred from enamines or dienamines with carbon disulfide at room temperature. The reaction of ketimines (Schiff bases) with carbon disulfide and sulfur yields 3H-1,2-dithiole-3-thiones or isothiazoline-5-thiones. The reaction of alkynes with sulfur and carbon disulfide leads to 2H-1,3-dithiole-2-thiones. Nitriles containing active methylene groups react with carbon disulfide and sulfur to form 5-amino-3H-1,2-dithiole-3-thiones. When isothiocyanates are used instead of CS₂, the reaction leads to δ⁴-4-amino-thiazoline-2-thiones.     

Benzofuroxans in heterocyclic synthesis : Reaction of benzofuroxans with dienamines; synthesis of a novel class of quinoxaline nn'-dioxide enamines

Benzofuroxanes react with dienamines to give a novel class of quinoxaline NN'-dioxide enamines in good yields.     

2-Halogenoethyl and 2-halogenoethylthiol esters of furan series carboxylic acids

The corresponding 2-chloroethyl (2-chloroethylthiol) esters are synthesized by the action of ethylene chlorohydrin (chloroethylmercaptan) on the acid chlorides of 5-nitrofuran carboxylic acid and 3-(5-nitrofuryl-2)acrylic acid. The acid chlorides of benzoic, furan carboxylic, and 3-(furyl-2)-acryllc acids react with ethylene sulfide, to give 2-chloroethyl esters of those acids. Ethylene oxide does not react with the acid chlorides of benzoic acid and furan series carboxylic acids either at room temperature or on heating at 50° for 1 hour.     

Dérivés de la dihydro-2,4 triazole-1,2,4 thione-3 et de l'amino-2 thiadiazole-1,3,4 à partir de nouvelles thiosemicarbazones d'esters

A new general synthesis of 4,5-disubstituted 2,4-dihydro-1,2,4-triazole-3-thiones is proposed. These heterocycles are obtained by the action of primary amines, arylhydrazines or aroylhydrazines on the thiosemicarbazones of eaters. These last compounds are prepared by action of chlorhydrates of iminoethers on thiosemicarbazide in dimethylformamide. These thiosemicarbazones react also with strong acids, acid anhydrides and chlorides; by thermolysis and they give 2-amino-1,3,4-thiadiazole derivatives. Also, two derivatives of 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole have been prepared.     

Cationic 1,3‐diazadienes in annulation reactions. Synthesis of pyrimidine,thiadiazinedioxide and triazine derivatives

Triazapentadienium iodides 2 prepared from N'‐thiocarbamoylformamidines 1 are efficient intermediates in heterocyclic synthesis. They react with ketenes, sulfenes, phenyl isocyanate or isothiocyanate and dimethyl acetylenedicarboxylate affording the corresponding dihydropyrimidinones 3 , thiadiazinedioxides 5 , triazinones 6 , triazinethiones 7 and pyrimidines 9 .     

Dienamines heterocycliques—I : Reaction de la base de fischer sur les ester acetyleniques

Dimethylacetylenedicarboxylate reacts with Fischer's base (1,3,3-trimethyl-2-methylene indoline) to give a zwitterionic intermediate which undergoes a Michael type addition in MeOH or cyclisation and ring opening in CHCl₃ to yield isomeric dienamines. Methyl propiolate, in addition to both the products observed previously, gives the ω-methoxycarboxylated Fischer's base in CHCl₃, whereas in CCl₄ a chlorinated dienamine is obtained. The solvent effect has been rationalised. Some dienamines react with tosylated oximes yielding azatrienes. The structures of the reaction products have been assigned on the basis of spectral data. A large difference of NMR chemical shift for the methyl groups bonded to the indoline ring has been observed depending upon the E and Z structure of the substituted Fischer's base.     

A convenient synthesis of amino-substituted 1,3,5-oxadiazinium salts

Diacyl chlorides react with dialkylcyanamide in the presence of a Lewis acid to give amino-substituted bis-1,3,5-oxadiazinium salts in excellent yields. A mechanism leads to the formation of the product has been postulated. All new compounds have been characterized by ¹H-nmr, ¹³C-nmr, ir-spectroscopy and elemental analysis.     

Enchainements heteroatomiques et leurs produits de cyclisation—I : Vinylogues de thioamides comme intermediaires de synthese d'acyl-2 thiophenes,thio-1 pyrannones-2 (thiones), dihydro-5,6 dithiinnes-1,2 dioxydes-1,1 et dithiinnes-1,2 dioxydes-1,1 substitues

2-Aminovinyl thioketones react with α-bromoketones, ketenes and sulfenes to give respectively substituted 2-acylthiophens, thiopyran(2H)-2-ones, 5,6-dihydro-1,2-dithiin-1,1-dioxides and 1,2-dithiin-1,1-dioxides by a cycloaddition process in good agreement with predictions based on calculated interactions between 2-aminovinyl thioketones and ketenes.     

The ‘inverse electron-demand’ Diels-Alder reaction in polymer synthesis. Part 5: Preparation and model reactions of some electron-rich bis-dienamines

The m- and p-phenylene-bridged bis-azolopyridinium salts have been synthesized and converted into the corresponding bis-dienamines by reaction with pyrrolidine. These dienamines react readily with dimethyl 1,2,4,5-tetrazine-dicarboxylate to yield the bis-azolylvinyl-pyridazines.     

PREPARATION AND SPECTRAL PROPERTIES OF SYMMETRICAL S-ARYL ARENESULFONOTHIOATES (THIOSULFONATES)

Abstract

Arenesulfinyl chlorides (4-XC₆H₄S(O)Cl); × = H, CH₃, F, Cl, Br) react with activated zerovalent zinc in benzene at 6 to 8°C to give symmetrical S-aryl arenesulfonothioates (thiosulfonates) in good to excellent yields. 2-and 3-Substituted arenesulfinyl chlorides (X = Cl, CH₃) give a mixture of products (disulfide, thiosulfinate, and/or thiosulfonate). 2,4,6-Triisopropylbenzenesulfinyl chloride reacts with zinc in 1,2-dimethoxyethane to give S-(2,4,6-triisopropylphenyl) 2,4,6-triisopropylbenzenesulfinothioate and bis(2,4,6-triisopropylphenyl) disulfide. Possible mechanisms for the reactions, the ¹H and ¹³C NMR spectra, and the chemical ionization and electron impact mass spectra of the thiosulfonates are discussed. The para carbon substituent chemical shifts (C_p-SCS) for the thiosulfonates and for symmetrical diaryl disulfides have been subjected to several dual substituent parameter (DSP) correlations.     

Diènamines hétérocycliques—II : Condensation de la base de fischer sur des aldéhydes aliphatiques satures. Formation d'azatriènes

Aliphatic aldehydes react with Fischer's base, 1,3,3-trimethyl-2-methylene indoline, to give new dienamines. When using acetaldehyde a substituted dienamine resulting from the reaction of two molecules of Fischer's base with the aldehyde is isolated. All products react with tosylated isonitrosomalonic derivatives yielding azatrienes which possess high absorption coefficients.     

Studies of acyl and thioacyl isocyanates—XII : The reactions of benzoyl and thiobenzoyl isocyanates with sulfonium ylides and with diazoalkanes

Benzoyl isocyanates react with ethyl (dimethylsulfuranilidene) acetate, dimethyl sulfonium phenacylide and dimethyloxosulfonium methylide to give the corresponding stable benzoylcarbamoyl- sulfonium ylides which on pyrolysis, are converted into oxazoles. However, with dimethylsulfonium phenacylide, thioacyl isocyanate affords the thiazole derivative. In connection with the formation of oxazoles, the reaction of benzoyl isocyanates with some diazoalkanes was also investigated: the products are not 1,2,3-triazolones as reported by Neidlein, but instead benzoylcarbamoyldiazo compounds which were thermally decomposed to oxazoles.     

Sels d'alkyloxyphosphonium—XV: Activation de l'hydroxyle anomere des 2,3,4,6-tetra-o-acyl-d-glucopyranoses—II. Preparation d'orthoesters et de thioglucosides

The joint action of tris(dimethylamino)phosphine (TDAP)-carbon tetrachloride on a tetra-O-acyl-2,3,4,6-d-glucopyranose yields two anomeric oxyphosphonium chlorides (ATDP salts). One of these anomeric forms is stable and the corresponding α-hexafluorophosphate is isolable as a solid. The alcohols react with the mixture of ATDP chlorides to yield 1,2-orthoesters, while thiophenol reacts to give the thioglucoside. These results are discussed and interpreted.     

9-Anthryldiazomethane in the Synthesis of Anthracene- Containing Polymers

Methods of the preparation of anthracene-containing monomers and polymers have been developed. They are based on the ability of 9-anthryldiazomethane to react with carboxylic groups of macromolecules and unsaturated carboxylic acids, to co-polymerize with diazoalkanes, and to generate 9-anthrylcarbene. These methods are used to obtain: (1) polymers with a low content (< 0.1 mole %) and different arrangement of anthracene groups in macromolecules (i. e., polymers with luminescent marks used to investigate macromolecules by luminescent methods) and (2) polymers with a high content (up to 100%) of anthracene-containing units, (which imparts to polymers specific photophysical and photochemical properties).     

Reactions ANC Rearangements of Carboxamides Phosphorylated by Tervalent Phosphorus Chlorides

Abstract

We have found that N-substituted amides of carboxylic or thiocarboxylic acids (I) react with tervalent phosphorus chlorides to give N- and O(S)-phosphorylated derivatives (II) which isomerise into imidoyl(thio)phosphonates (III). The factors determining the ability of the initial products (II) and their iminated derivatives (IV) to participate in diad and triad rearrangements have also been studied.     

Triorganosilicon(IV) complexes as biocides: Synthetic,spectroscopic and biological studies of N SH and N OH fluoroimines and their chelates

A facile synthesis and study of the stereochemistry and biochemical aspects of some triorganosilicon(IV) complexes derived from fluoroimines having N S and N O systems are reported. The fluoroimines were prepared by the condensation of 2-fluorobenzaldehyde and 1-(2-fluorophenyl)ethanone with semicarbazide and thiosemicarbazide. These imines react with triorganosilicon(IV) chlorides to yield compounds having Si? O/Si? S and Si ← N bonds. The structures of the compounds have been elucidated by physicochemical and spectral (UV, IR, ¹H NMR, ¹³C NMR and ⁹F NMR) studies which clearly point to a trigonal bipyramidal geometry around silicon(IV), as the active lone pair of nitrogen is also included in the coordination sphere. In the search for better fungicides and bactericides, studies were conducted to assess the growth-inhibiting potential of the synthesized complexes against various pathogenic fungal and bacterial strains. These studies demonstrate that the concentrations reached levels which are sufficient to inhibit and kill the pathogens.     

4-Diazomethyl-7-Methoxycoumarin as a New Type of Stable Aryldiazomethane Reagent

Diazoalkanes have been widely used as versatile alkylating agents. One of the principal advantages of using diazoalkane is that no side reaction product other than gaseous nitrogen is produced during alkylation process. However, most diazoalkanes suffer from the fact that they are unstable, sometimes explosive, and are not available in pure state. They have to be only used in the solutions prepared from appropriate precursors just before use. Thus, only a few compounds have been developed so far as solid diazoalkane reagents¹ of practical value which are suitable for labeling acidic substances for analytical and biochemical purposes. We have now obtained 4-diazomethyl-7-methoxycoumarin 4 as a new type of crystalline aryldiazomethane having excellent purity and stability as well as enough reactivity to produce a fluorophore with carboxylic or sulfonic acid by esterification.     

Synthesis of N-substituted pyrroles from 1-R-3-R1-3,4-dichlorobutanones

Reaction of acyl chlorides or methallyl chlorides in the present of aluminum chloride gives 1-R-3-R¹-3,4-dichlorobutanones which give 1,2- and 1,2,4-substituted pyrroles with ethanolamine. The dichlorobutanones react with glycine and -alanine to give the N-pyrrolyl derivatives of acetic and propionic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1181–1184, September, 1990.     

稀土与华法灵、水杨酸三元配合物的合成和抗凝血作用研究

用氯化稀土与华法灵钠、水杨酸钠在不同介质中制备了稀土三元配合物, 所试验各种制备方法均可获得恒定组成的配合物REL₂L'•2H₂O (HL＝华法灵离子; HL'＝水杨酸离子). 通过元素分析、红外光谱、核磁共振氢谱、X射线衍射、摩尔电导、电子吸收光谱和溶解性试验对配合物进行了表征. 抗凝血试验表明稀土三元配合物具有优良的抗凝血性质.