Azaindole derivatives. 67. Synthesis of N-substituted 1-benzyl-4-methyl-5-cyano-6-amino-7-azaindoles

N-substituted 1-benzyl-4-methyl-5-cyano-6-amino-7-azaindoles have been synthesized from the respective 1-benzyl-4-methyl-5-cyano-6-chloro(and 6-hydroxy)-7-azaindoles. The effect of the 5-cyano group on the oxidation-reduction processes accompanying nucleophilic replacement of chlorine in 6-chloro-7-azaindoles by primary and secondary amines has been considered. 7-Azaindoline compounds were dehydrogenated by chloranil to N-substituted 1-benzyl-4-methyl-5-cyano-6-amino-7-azaindoles.For communication 66, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 91–96, January, 1986.     

Synthesis of naphthyridinone derivatives as potential antimalarials

In this paper we present the synthesis of 8-(4′-amino-1′methyl-butylamino)-5-(β,β,β-trifluoroethoxy)-1,6-naphthyridine ( 4 ), 8-(4′-amino-1′methylbutylamino)-6-methyl-1,6-naphthyricline-5-one ( 5 ), two 1-alkyl-3-(4′-amino-1′-methylbutylamino)-7-methyl-1,8-naphthyridin-4-ones ( 20a ) and 20b ), 3-(1′-amino-4′-methylbutyl-amino)-l-ethyl-7-methyl-l,8-naphthyridin-4-one (20c), and 4-(4′-diethylamino-1′-methylbutylamino)-7-methyl-1,7-naphthyridin-8-one ( 28 ). The compounds were evaluated for antimalarial activity in the Plasmodium berghei screen and found to be inactive.     

Unequivocal syntheses of 6-methyl- and 6-phenylisoxanthopterin

Although 6-methyl- ( 1 ) and 6-phenylisoxanthopterin ( 2 ) have previously been synthesized, the requirement of high purity necessary for immunological testing has necessitated our development of the first reported synthesis of these compounds by unequivocal methods. In the process of so doing four new pyrazines, ethyl 3-amino-5-chloro-6-methyl-2-pyrazinecarboxylate ( 11 ), N,N-dimethyl-N'-(6-chloro-3-cyano-5-phenylpyrazin-2-yl)methanimidamide ( 16 ), 2-amino-3-ethoxycarbonyl-5-phenylpyrazine 1-oxide ( 19 ), and ethyl 3-amino-5-chloro-6-phenyl-2-pyrazinecarboxylate ( 20 ) were synthesized. Four new pteridines, 7-methoxy-6-methyl-2,4-pteridinediamine ( 7 ), 7-methoxy-6-phenyl-2,4-pteridinediamine ( 17 ), 2-amino-7-ethoxy-6-methyl-4(3H)-pteridinone ( 12 ), and 2-amino-7-ethoxy-6-phenyl-4(3H)-pteridinone ( 21 ) have also been synthesized enroute to these isoxanthopterins.     

MO-berechnungen an heterocyclen—VII : Tautomerieprobleme an substituierten 1,3,8-triazaindolizinen

The electronic spectra of some derivatives of 5-hydroxy-7-methyl-1,3,8-triazaindolizine have been calculated with the PPP-procedure. With the electronic spectra and heats of atomization the tautomeric structures of the compounds 6-ch]or-5-hydroxy-7-methyl-1,3,8-triazaindolizine, 6-brom-5-hydroxy-7-methyl-1,3,8-triazaindolizine, 6-carboxy-5-hydroxy-7-methyl-1,3,8-triazaindolizine, 2-carboxy-5-hydroxy-7-methyl-1,3,8-triazaindolizine, 2-mercapto-5-hydroxy-7-methyl-1,3,8-triazaind and 5-amino-7-methyl-1,3,8-triazaindolizine are discussed. The possible structures of the compounds 5-hydroxy-7-methyl-1,3,8-triazaindolizine, 5-hydroxy-7-methyl-1,2,8-triazaindolizine and 5-hydroxy-7-methyl-1,2,3,8-tetrazaindolizine depending on the pH-value of the solution have been investigated.     

2,3,5,8(1)-Tetrahydroimidazo[1,2-a]pyrimidine-2,5-dione derivatives

The corresponding ylidene, azomethine, and azo derivatives of 2,3,5,8(1)-tetrahydroimidazo [1,2-a]pyrimidine-2,5-dione were synthesized by reaction of 7-methyl-and 6-bromo-7-methyl-2,3,5,8(1)-tetrahydroimidazo[1,2-a]pyrimidine-2,5-diones with aldehydes, insatin, aromatic nitroso compounds, and arenediazonium salts. Ylidene derivatives of 7-methyl-2,3,5,8(1)-tetrahydroimidazo[1,2-a]pyrimidine-2,5-dione were also obtained by reaction of 2-amino-4-methyl-6-oxo-1,6-dihydro-1-pyrimidylacetic acid with carbonyl compounds.     

Piperidine-mediated synthesis of thiazolyl chalcones and their derivatives as potent antimicrobial agents

A series of new thiazolyl chalcones, 1-[2-amino-4-methyl-1,3-thiazol-5-yl]-3-aryl-prop-2-en-1-one were prepared by piperidine mediated Claisen-Schmidt condensation of thiazolyl ketone with aromatic aldehyde. These chalcones on cyclisation gave 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyridine-3-carbonitrile and 2-amino-6-(2-amino-4-methyl-1,3-thiazol-5-yl)-4-aryl-4H-pyran-3-carbonitrile. The result showed that the compounds exhibited marked potency as antimicrobial agents.     

Solvent polarity indicators: Extraction of some coumarin indicator dyes

Study of the extraction of ten different coumarins (unsubstituted, 6-methyl-, 7-methyl-, 4-hydroxy-, 7-hydroxy-, 7-hydroxy-4-methyl-, 7-methoxy-, 7-amino-4-methyl-, 7-diethyl-amino-4-methyl-, and 3-carboxy-) with nine organic solvents shows that the percentage extraction is generally high. Cyclohexanone and heptane were found to be, respectively, the most and least effective extracting solvents for the compounds under study. The results are discussed in terms of the effect of different solvent polarity parameters on the extraction process.     

Synthesis of new pyrido[2,3-d]pyrimidine derivatives

The mutual condensation of 4-aminouracil or 2,4-diamino-6-hydroxypyrimidine with bisacetonitrile and aldehydes was used to synthesize 2,4-dioxo-5-R-7-methyl-6-cyano-1,2,3,4,5,8-hexahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine derivatives, which were oxidized with chromic anhydride to the corresponding 2,4-dioxo-5-R-7-inethyl-6-eyano-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine and 2-amino-4-oxo-5-R-7-methyl-6-cyano-3,4-dihydro[2,3-d]pyrimidines. The IR and UV spectra of the synthesized compounds were recorded.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 422–425, March, 1972.     

Synthesis of pyrrolopyridines (azaindoles)

Improved, convenient, and reliable routes for the synthesis of 4-, 5-, 6-, and 7-azaindole, 7-methyl-4-azaindole, 7-methyl-6-azaindole, and the hitherto unreported 7-amino-4-azaindole are described. The syntheses have been accomplished either by significant modifications to established procedures or by new methods which afford the compounds in improved yields.     

Synthesis and chromatographic enantioresolution of anti-HIV quinolone derivatives

The successful enantioseparation of five 6-desfluoroquinolones with three polysaccharide-based stationary phases (namely, the cellulose-based Chiralpak IB and the two amylose-based Chiralpak AD-H and Lux Amylose-2) is herein described. The investigated species differ for the nature of substituents and/or the position of the stereogenic centre on the quinolone scaffold.The effect on the enantioseparation performance exerted by the different morphology of the cellulose-based and amylose-based polymers, was systematically evaluated for all compounds. In this frame, the impact of alternative alcoholic (ethanol, 2-ethoxyethanol, methanol, 2-propanol) and acidic (acetic, methanesulfonic and trifluoroacetic acid) modifiers as well as of a “non-standard” solvent (chloroform), was investigated in normal phase conditions along with the stereo-electronic peculiarities of the selected polymers. While 7-[4-(1,3-benzothiazol-2-yl)-2-methyl-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxylic acid (1) was enantioresolved with conventional normal-phase conditions by means of the largely employed amylose-based Chiralpak AD-H column, the recruitment of a bulky alcohol (2-ethoxyethanol) succeeded in the enantioresolution of 6-amino-1-methyl-7-[2-methyl-4-(2-pyridinyl)-1-piperazinyl]-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid (2) and 6-amino-1-[1-(hydroxymethyl)propyl]-4-oxo-7-(4-pyridin-2-ylpiperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid (3) with the same column. The use of the amylose-based Lux Amylose-2 column, carrying both an electro-withdrawing (chlorine) and an electro-donating (methyl) group on the carbamate residue, allowed to get 6-amino-1-methyl-4-oxo-7-[3-(2-pyridinyl)-1-pyrrolidinyl]-1,4-dihydro-3-quinolinecarboxylic acid hydrochloride (4) enanantioresolved, and 6-amino-1-methyl-4-oxo-7-(3-pyridin-2-ylpiperidin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid (5) enantioseparated.     

Synthesis and Tautomeric Structure of 7-Arylhydrazono-7H-[1,2,4]Triazolo[3,4-b][1,3,4]Thiadiazines

Two synthetic approaches were developed for the title compounds 8a-g via coupling of diazotized anilines with 7-acetyl-6-methyl-3-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazine 7 , and reaction of N-aryl 2-oxopropanehydrazonoyl chlorides 9 with 4-amino-3-mercapto-5-phenyl-1,2,4-triazole 1 . The tautomeric structures of 8 were elucidated by their spectral analyses and correlation of their acid dissociation constants with Hammett equation.     

1-(取代吡唑-4-甲酰基)吡唑类化合物的合成及生物活性研究

设计合成了25个新型1-取代吡唑甲酰基吡唑系列衍生物,化合物结构经¹HNMR、元素分析、IR和MS确证.生物活性测试结果表明,该类化合物具有一定除草活性,讨论了其结构与活性的关系.     

Cyclic condensations of 2-amino-1,3,4-thiadiazole with 1,3-dicarbonyl compounds

The reactions of 2-amino-1,3,4-thiadiazole with 1,3-dicarbonyl compounds are described. 2,4-Pentanedione gave 2-thiocyanato-4,6-dimethylpyrimidine while diethylmalonate and ethyl acetoacetate yielded 5-hydroxy-7H-1,3,4-thiadiazolo[3,2-a]pyrimidin-7-one and 7-methyl-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one, respectively. The structure of the latter compound was confirmed by a synthesis of the alternative isomeric structure (5-methyl-7H-1,3,4-thiadiazolo[3,2-a]pyrirnidin-7-one) from 2-amino-1,3,4-thiadiazole and α-bromocrotonic acid.     

Parallel approach for solution-phase synthesis of 2-quinoxalinol analogues and their inhibition of LPS-induced TNF-alpha release on mouse macrophages in vitro

A parallel solution-phase synthesis of 2-quinoxalinol analogues is described. The key step-simultaneous reductions of m-Ar(NO(2))(2) to m-Ar(NH(2))(2) was investigated extensively. We obtained preliminary pharmacological activity of those analogues for the inhibition of LPS-induced TNF-alpha release on mouse macrophage in vitro. Two compounds revealed inhibitory activity, with IC(50) values of 0.40 microM (7-amino-6-[(3-methoxypropyl)amino]-3-methyl-2-quinoxalinol) and 2.2 microM (7-amino-6-[(3-butoxypropyl)amino]-3-methyl-2-quinoxalinol), respectively.     

Synthesis of o-bisazo-1H-pyrazoles and study of their cyclization to give compounds with a 1,2,4-triazine ring

The reactivities of o-hydroxyarylazo-1H-pyrazoles in reactions involving the formation of a 1,2,4-triazine ring in alkaline and acidic media as a function of the character of the substituent in the 4 position of the 1H-pyrazole and the temperature were studied. o-Hydroxyarylazo-1H-pyrazoles and o-hydroxyarylbisazo-1H-pyrazoles, as well as condensed 1,2,4-triazines, were synthesized by diazo coupling of diazotized 5-amino-3-methyl-1R-pyrazoles and o-aminoazobipyrazoles with azo components, viz., 2,3-dihydroxynaphthalene, 1-methyl-3-hydroxyindole, 3-methyl-1-phenyl-5-pyrazolone, and 5-amino-3-methyl-1R-pyrazoles. Azo compounds that undergo ring closure to a triazine ring with the liberation of water when solutions are heated are obtained in the case of 2,3-dihydroxynaphthalene; only azo and o-bisazo compounds were synthesized in the case of 5-aminopyrazoles. An o-bisazo compound that is converted to a triazine when the hydroxy group is replaced by chlorine was isolated in the case of 5-pyrazolone; only a triazine was obtained with 1-methyl-3-hydroxyindole. The compounds obtained were characterized by their IR, UV, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 805–812, June, 1979.     

Synthesis, and antitumor activity of some N1-(coumarin-7-yl) amidrazones and related congeners

A series of new N1-(coumarin-7-yl)amidrazones incorporating N-piperazines and related congeners were synthesized by reacting the hydrazonoyl chloride derived from 7-amino-4-methylcoumarin with the appropriate piperazines. The chemical structures of the newly prepared compounds were supported by elemental analyses, 1H-NMR, 13C-NMR, and ESI-HRMS spectral data. The antitumor activity of the newly synthesized compounds was evaluated. Among all the compounds tested, 7-{2-[1-(4-(1-benzyl-2-ethyl-4-nitro-1H-imidazol-5-yl)piperazin-1-yl)-2-oxopropylidene]hydrazinyl}-4-methyl-2H-chromen-2-one (3n) was the most potent against MCF-7 and K562 cells, with IC?? values of 20.2 and 9.3 μM, respectively.     

Syntheses,characterization and x-ray crystal structures of copper(II) and nickel(II) complexes of tridentate monocondensed diamines

The syntheses and characterization of three compounds involving tridentate “half-units” 7-amino-4-methyl-5-aza-3-hepten-2-one (HAMAH) and 8-amino-4-methyl-5-aza-3-octen-2-one (HAMAO) are described. Cu(II) and Ni(II) complexes with HAMAH have been isolated as four-coordinate complexes, the fourth coordination site being taken by imidazole, and have been structurally characterized. A Cu(II) complex involving HAMAO has been isolated as a highly insoluble polymeric species. Hydroxo bridging between the metal centres is indicated.     

Ion-selective electrodes in titrations involving azo-coupling reactions: Part 2. Titrations with diazonium salts derived from 1-aminonaphthalenes and 1-amino-9,10-anthraquinone

Lipophilic arenediazonium salts dreived from 1-aminonaphthalene, 1-amino-4-bromonaphthalene, 1-amino-4-nitronaphthalene and 1-amino-9,10-anthraquinone were tested as titrants for determination of aromatic hydroxy compounds, amines, and compounds containing active methylene groups, usually at the 10^?2 M level. The potentiometric titrations were monitored with indicator electrodes selective for organic cations which were based on PVC membranes plasticized with 2-nitrophenyl alkyl ethers (where alkyl is n-octyl or 2-ethylhexyl). Titrations of 11 compounds ranging from 1,2-diaminotoluene to 1-phenyl-3-methyl-5-pyrazolone were examined; 4-bromo-1-naphthalenediazonium chloride seemed to be the most widely applicable titrant.     

Synthesis of N-Substituted Derivatives of 2-(4-Amino-2-methyl-1H-indol-3-yl)- and 2-(6-Amino-2-methyl-1H-indol-3-yl)acetic Acids

A method was developed for the production of indole compounds containing an amino group at positions 4 and 6 of the benzene ring on the basis of the indolization of the 3-acetylaminophenylhydrazone of ethyl levulinate. A series of derivatives of 2-(4-amino-2-methyl-1H-indol-3-yl)- and 2-(6-amino-2-methyl-1H-indol-3-yl)acetic acids at the 4- and 6-amino group were synthesized.     

Synthesis of new 1,2,4-triazole[3,4-b][1,3,4]thiadiazoles bearing pyrazole as potent antimicrobial agents

A new series of 6-(aryl/heteryl)-3-(5-methyl-1-phenyl-1H-4-pyrazolyl)[1,2,4]triazolo[3,4-b][1,3,4]thiadiazoles (7a-j) has been synthesized by the reaction of 4-amino-5-(5-methyl-1-phenyl-1H-4-pyrazolyl)-4H-1,2,4-triazol-3-yl-hydrosulfide (6) with POCl(3) and the corresponding aryl/heteryl carboxylic acid, in ethanol at reflux temperature for 12 h. All the synthesized compounds were tested for in vitro activities against certain strains of bacteria such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and fungi such as Aspergillus niger, Aspergillus nodulans, Alternaria alternate. Compounds having 4-chlorophenyl (7d), 4-aminophenyl (7f), 4-nitrophenyl (7h) and 3-pyridyl (7i) substituents at 6-position of thiadiazole ring, showed marked inhibition of bacterial and fungal growth nearly equal to the standards. The other new compounds also showed appreciable activity against the test bacteria and fungi.