Synthesis and antibacterial activity of new N-[2-(thiophen-3-yl)ethyl] piperazinyl quinolones

As a part of continuing search for potential antibacterial agents in the quinolones field, we have synthesized novel quinolone agents bearing N-[2-(thiophen-3-yl)ethyl] piperazinyl moiety in the 7-position of the quinolone ring. In vitro antibacterial evaluation of the target compounds showed that N-[2-(thiophen-3-yl)ethyl] group attached to piperazine ring served as promising C-7 substituent for piperazinyl quinolone antibacterials. Among these derivatives, ciprofloxacin analogues, containing N-[2-(thiophen-3-yl)-2-hydroxyiminoethyl] or N-[2-(thiophen-3-yl)-2-methoxyiminoethyl] residue provided a high inhibition against all the tested Gram-positive organisms including methicillin-resistant Staphylococcus aureus comparable or superior with respect to the reference drugs norfloxacin and ciprofloxacin.     

N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)酰胺类新化合物的合成及生物活性

以N-吡啶基吡唑甲酸和2-氨基-3-甲基苯甲酸为起始原料,经由亲核加成、环化和酰化等多步反应合成了一系列结构新颖的N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)酰胺类化合物.测试了所合成化合物的杀虫及抑菌活性,结果表明,新化合物大多化合物在200 mg·L^-1浓度下对东方粘虫(Mythimna separataWalker)具有一定的杀虫活性,尤其是N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)乙酰胺(8a)和N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-3-氯-2,2-二甲基丙酰胺(8e)致死率可达70%;部分化合物在50 mg·L^-1浓度下对油菜菌核病菌的抑菌活性相对较好(54.5%~63.6%),优于triadimefon和chlorantraniliprole;部分化合物如N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-3,3-二甲基丁酰胺80和N-(2-(5-(3-溴-1-(3-氯吡啶-2-基)-1H-吡唑-5-基)-1,3,4-噁二唑-2-基)-4-氯-6-甲基苯基)-4-氟苯甲酰胺(8h)对苹果轮纹病菌具有中等抑菌活性.值得注意的是,化合物8e的杀粘虫活性和对油菜菌核病菌的抑菌活性都较为突出,可用作新农药创制研究的新型参考结构.     

SYNTHESIS,CHARACTERIZATION, CRYSTAL STRUCTURE,AND DFT STUDY OF N-(2-METHOXY-5- (4,4,5,5-TETRAMETHYL-1,3,2-DIOXABOROLAN-2-YL) PYRIDIN-3-YL)CYCLOPROPANESULFONAMIDE

Journal of Structural Chemistry - N-(2-methoxy-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-3-yl)cyclopropanesulfonamide is an organic intermediate with borate and sulfonamide groups,...     

Novel approach to aminocarboranes by mild amidation of selected iodo-carboranes

A mild protocol for the palladium-catalyzed Buchwald-Hartwig amidation of icosahedral carboranes is described. Employing 2-dicyclohexylphosphino-2'-(N,N-dimethylamino)biphenyl (1) as a ligand and K(3)PO(4) as a base, benzamide, trifluoroacetamide, acetamide, and formamide were coupled to a series of mono- and di-iodo carboranes furnishing the respective carborane derivatives in good to excellent yields. Subsequent base-mediated saponification of the trifluoroacetamide derivatives was shown to provide the free aminocarboranes. The structures of N-(1,7-dicarba-closo-dodecaboran-9-yl)benzamide (8a), N-(1,7-dicarba-closo-dodecaboran-9-yl)trifluoroacetamide (8b), N-(1,12-dicarba-closo-dodecaboran-2-yl)benzamide (10a), N-(1,2-dicarba-closo-dodecaboran-9-yl)benzamide (12a), N-(1,2-dicarba-closo-dodecaboran-9-yl)acetamide (12c), N-(1,2-dicarba-closo-dodecaboran-9-yl)formamide (12d), N-(1,2-dicarba-closo-dodecaboran-3-yl)benzamide (13a), N,N'-(1,7-dicarba-closo-dodecaboran-9,10-diyl)dibenzamide (15a), and N,N'-(1,7-dicarba-closo-dodecaboran-9,10-diyl)bis(trifluoroacetamide) (15b) have been established through X-ray single-crystal diffraction studies.     

4-(5-喹啉-3-基-四氮唑-2-基)丁胺的合成

三苯基膦钯催化3-溴喹啉完成氰化取代制得3-氰喹啉(1);1与叠氮化钠经[2+3]环加成合成了3-(2H-四氮唑-5-基)喹啉(2);2与N-(4-溴丁基)邻苯二甲酰亚胺反应制得2-[4-(5-喹啉-3-基-四氮唑-2-基)丁基]异吲哚-1,3-二酮(3);3经肼解合成了4-(5-喹啉-3-基-四氮唑-2-基)丁胺(4...     

Derivatives of the N-(pyrid-2-yl)amides of 3-aminocrotonic acid as chelating ligands

New chelating ligands, N-(pyrid-2-yl)amides of 4,4,4-trichloro-3-amino-2-cyanocrotonic acid have been synthesized from N-(pyrid-2-yl)amides of cyanoacetic acid and CCl₃CN. It has been demonstrated that by the action of butylthiodibutylborane they form binuclear boron chelate complexes. Analogous chelates have also been obtained from the N-(pyrid-2-yl)amides of acetoacetic and 4,4,4-trichloro-3-aminocrotonic acids.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 974–979, April, 1992.     

Protonation sites and hydrogen bonding in mono-hydrobromide salts of two N,4-diheteroaryl 2-aminothiazoles

Structural Chemistry - The synthesis and structural characterization of N-(6-methoxypyridin-3-yl)-4-(pyridin-2-yl)thiazol-2-amine mono-hydrobromide monohydrate (3) and...     

Synthesis of 7-azabicyclo[2.2.1]heptane and 2-oxa-4-azabicyclo[3.3.1]non-3-ene derivatives by base-promoted heterocyclization of alkyl N-(cis(trans)-3,trans(cis)-4-dibromocyclohex-1-yl)carbamates and N-(cis(trans)-3,trans(cis)-4-dibromocyclohex-1-yl)-2,2,2-trifluoroacetamides

We have studied the base-promoted heterocyclization of alkyl N-(cis(trans)-3,trans(cis)-4-dibromocyclohex-1-yl)carbamates and N-(cis(trans)-3,trans(cis)-4-dibromocyclohex-1-yl)-2,2,2-trifluoroacetamides, investigating the effect of the nitrogen protecting group and the relative configuration of the leaving group at C3 and C4 on the outcome of this reaction. We have observed that the sodium hydride-promoted heterocyclization of alkyl N-(cis-3,trans-4-dibromocyclohex-1-yl)carbamates (10, 12, 14, 16, 18) is a convenient method for the synthesis of 7-azabicyclo[2.2.1]heptane derivatives. For instance, the reaction of tert-butyl N-(cis-3,trans-4-dibromocyclohex-1-yl)carbamate (10) with sodium hydride in DMF at room temperature provides 2-bromo-7-[(tert-butoxy)carbonyl]-7-azabicyclo[2.2.1]heptane (2) (52% yield), whose t-BuOK-promoted hydrogen bromide elimination affords 7-[(tert-butoxy)carbonyl]-7-azabicyclo[2.2.1]hept-2-ene (31) in 78% yield, an intermediate in the total synthesis of epibatidine (1). However, the NaH/DMF-mediated heterocyclization of alkyl N-(trans-3,cis-4-dibromocyclohex-1-yl)carbamates (11, 13) is a more structure dependent reaction, where the nucleophilic attack of the oxygen atom of the protecting group controls the outcome of the reaction, giving rise to benzooxazolone and 2-oxa-4-azabicyclo[3.3.1]non-3-ene derivatives, respectively, from low to moderate yields, in complex reaction mixtures. Conversely, the NaH/DMF heterocyclizations of N-(cis-3,trans-4-dibromocyclohex-1-yl)-2,2,2-trifluoroacetamide (40) or N-(trans-3,cis-4-dibromocyclohex-1-yl)-2,2,2-trifluoroacetamide (42) are very clean reactions giving 7-azabicyclo[2.2.1]heptane or 2-oxa-4-azabicyclo[3.3.1]non-3-ene derivatives, respectively, in good yields. Finally, a mechanistic investigation, based on DFT calculations, has been carried out to rationalize the formation of the different adducts.     

Bioisostere of Sulfonyl Moiety-The Synthesis of New ALS Inhibitors N-(Asymmetry Disubstituted Phosphoryl)-N'-(4,6-dimethoxypyrimidin-2-yl) Ureas

IntroductionAcetolactatesynthase(ALS)isthefirstcommonenzymeinthebiosyntheticpathwayforthebranched-chainaminoacidsvaline,leucineandisoleucine.Itisaveryeffectivetargetsiteforherbicidalaction,whichistheselectedmodeofactionasitisspecificforplantsanddoesnotaffectmammals.Sulfonylureaherbicidesareanewclassofherbicidesdiscoveredinthemid-l97O'sl.ItsmodeofactionhasbeenestablishedtobeinhibitorytowardALS2.Muchattentionhasbeenfocusedonthiskindofcompounds,sincetheyhaveexcellentactivity,ahighdegreeofseIe…     

SYNTHESIS,SPECTRAL STUDIES,AND ANTIMICROBIAL ACTIVITIES OF [N-(UN)ALKYLATED-2-ARYLINDOL-3-YL]THIOCARBOXAMIDES

A series of [N-(un)alkylated-2-arylindol-3-yl]thiocarboxamides(6) have been synthesized by the condensation of alkyl [N-(un)alkylated-2-arylindol-3-yl]dithiocarboxylates (5) with appropriate secondary amines in absolute alcohol. Compound 5 was prepared by the reaction of N-(un)alkylated-2-arylindoles with carbon disulphide in the presence of potassium-t-butoxide followed by alkyl iodide under nitrogen atmosphere. All of the compounds have been characterized on the basis of their elemental and spectral data and have been screened for their antibacterial and antifungal activities. Some of the synthesized compounds have shown promising activity.     

Oxidative Recyclization of 4,6,7-Trichloro-5-hydroxy-2-(2-pyrimidylamino)-2,3-dihydrobenzo[b]furan

When 4,6,7-trichloro-5-hydroxy-2-(2-pyrimidylamino)- 2,3-dihydrobenzo[b]furan reacted with phenyliodoso diacetate, an unexpected oxidative recyclization was observed to give 3-(3,5,6-trichloro-1,4-benzoquinon-2-yl)imidazo[1,2-a]pyrimidine. 2-[N-2-(3,5,6-Trichloro-1,4-benzoquinon-2-yl)ethenylamino]pyrimidine is the intermediate product in the conversion.     

Dimerization of N-(pyrid-2-YL)- and N-(5-methylpyrid-2-YL) cyanoacetamides by the action of butylthiodibutylborane

The reaction of N-(pyrid-2-yl) and N-(5-methyipyrid-2-yl) cyanoacetamides with butylthiodibutylborane in a 23 ratio leads to the formation of trinuclear complex boron compounds, the alcoholysis of which gave N,N-di(pyrid-2-yl) 3-amino-2-cyanopent-2-ene-1,5-diamides. The latter are dimers of the starting cyanamides, which are capable of acting as hexadentate chelating agents.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 168–173, January, 1991.     

一步法合成N-1,3-二羟基丙烷-2-基烷基乙酰胺

以5-氨基烷基-2,2-二甲基-1,3-二噁烷为起始原料, 乙酸酐为酰化剂, 一步法选择性地合成氨基二醇类氨基乙酰化产物N-1,3-二羟基丙烷-2-基烷基乙酰胺. 该方法操作简便, 收率高. 所合成的4个新化合物的结构均经FTIR, ¹H NMR, ¹³C NMR及HRMS确证. N-3-(1,3-二羟基丙烷-2-基)丙基乙酰胺(1a)作为关键的中间体, 可以用于HIV-1 Tat/ PCAF BRD抑制剂4的合成.     

Synthesis of compounds with a four-coordinate boron atom from 2-aminobenzazoles and nitriles

The reactions of 2-aminobenzazoles with nitriles in the presense of organoboranes results in the formation of novel tricyclic chelate boron compounds with N-(benzazol-2-yl)amidines as ligands, N-(Benzothiazol-2-yl)-p-chlorobenzamidine was prepared from 2-aminobenzothiazole and p-chlorobenzonitrile via the corresponding chelate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1019–1021, April,.     

Synthesis of 3-(2-Aryloxazolidin-3-yl)tropanes

We obtained 3-(2-aryloxazolidin-3-yl)tropanes by reaction of aromatic aldehydes with 3-[N-(2-hydroxyethyl)amino]tropane. We obtained 3-benzyloxazolidine-2-spiro-3'-(8'-carbethoxy)nortropane by reaction of benzylaminoethanol with 8-carbethoxynortropan-3-one.     

Sulfanyl chloride induced heterocyclization of N-(pyrazolyl)styrylacetamides

Heterocyclization of N-(pyrazol-3-yl)styrylacetamides with arenesulfenyl chlorides yields the corresponding tetrahydrofuran-2-iminium perchlorates isolable after chromatography as trans-5-aryl-4-(arylthio)tetrahydrofuran-2-ones and 5-aryl-4-(arylthio)-1-(pyrazol-3-yl)pyrrolidin-2-ones, with the latter predominating. N-(Pyrazol-4-yl)styrylacetamides react under analogous conditions to give 5-aryl-4-(arylthio)-1-(pyrazol-4-yl)pyrrolidin-2-ones, 4-aryl-3-(arylthio)-4-chloro-N-(1-methylpyrazol-4-yl)butanamides, and tetrahydrofuran-2-iminium perchlorates which, when chromatographed, produce 5-aryl-4-(arylthio)dihydrofuran-2(3H)-ones and 4-aryl-3-(arylthio)-4-methoxy-N-(1-methyl-1H-pyrazol-4-yl)butanamides.     

Synthesis and cytotoxic activity of some novel N-pyridinyl-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide derivatives

A series of novel compounds bearing imidazo[2,1-b]thiazole scaffolds were designed and synthesized based on the optimization of the virtual screening hit compound N-(6-morpholinopyridin-3-yl)-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide (5a), and tested for their cytotoxicity against human cancer cell lines, including HepG2 and MDA-MB-231. The results indicated that the compound 2-(6-(4-chlorophenyl)imidazo[2,1-b]thiazol-3-yl)-N-(6-(4-(4-methoxybenzyl)piperazin-1-yl)pyridin-3-yl)acetamide (5l), with slightly higher inhibition on VEGFR2 than 5a (5.72% and 3.76% inhibitory rate at 20 μM, respectively), was a potential inhibitor against MDA-MB-231 (IC(50) = 1.4 μM) compared with sorafenib (IC(50) = 5.2 μM), and showed more selectivity against MDA-MB-231 than HepG2 cell line (IC(50) = 22.6 μM).     

Boron chelate complexes with 4-[N-(R-pyrid-2-yl)carbamoyl]-3-amino-2-cyanobuten-2-ic acid esters (codimers of N-(R-pyrid-2-yl)amides and the ethyl ester of cyanoacetic acid)

Mono- and binuclear boron chelates have been synthesized by the action of butylthiodibutylborane on the ethyl esters of 4-[N-(R-pyrid-2-yl)carbamoyl]-3-amino-2-cyanobuten-2-ic acids (codimers of N-(R-pyrid-2-yl) amides and the ethyl ester of cyanoacetic acid). Complexes of this type can exist in solution in the form of two tautomers: acetamide acid derivatives or the corresponding ketene N,O-acetals.N. D. Zelinski Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2162–2170, September, 1992.     

Cyclocondensation of n-(prop-2-yn-1-yl)- and n-(penta-2,4-diyn-1-yl)- <Emphasis Type="Italic">o</Emphasis>-phenylenediamines with phenyl isothiocyanate and carbon disulfide

The cyclocondensation of N-(prop-2-yn-1-yl)-o-phenylenediamines with phenyl isothiocyanate leads to the formation of 1-(prop-2-yn-1-yl)-1,3-dihydro-2H-benzimidazole-2-thiones irrespective of the substituent nature at the triple bond. Reactions of both mono- and diacetylenic derivatives of o-phenylenediamine with carbon disulfide in the presence of KOH proceed with the formation of two heterocyclic nuclei simultaneously. From N-(prop-2-yn-1-yl)-o-phenylenediamines containing an aryl substituent at the triple bond, and N-(penta-2,4-diyn-1-yl)-o-phenylenediamines 2-methylidene-2,3-dihydro[1,3]thiazolo[3,2-a]benzimidazoles are formed. The latter are readily isomerized under the action of base giving thiazolo[3,2-a]benzimidazoles. The cyclocondensation of N-(alk-2-yn-1-yl)-o-phenylenediamines with CS₂ leads to [1,3]thiazino[3,2-a]benzimidazoles.     

SYNTHESIS AND REACTVITY OF N-[N-PHOSPHORAMIDO-1H-BENZIMIDAZOL-2-YL] IMIDATES

N-(-1H-Benzimidazol-2-yl) imidates 1a–c react with chlorophosphoramide to give the N-[-1-N,N,N′,N′-tetramethylphosphoramidoyl-1H-benzimidazol-2-yl]-imidates 2a–c or with dichlorophosphoramide to yield the bis[(N-1-benzimidazol-2-yl)-imidate] phosphoramide derivatives 3a–b. The reaction of compounds 2a–c toward primary amines is studied. The obtained amidine derivatives 4a–b were unambiguously characterized by different spectroscopic techniques (IR, ¹H, ¹³C, and ³¹P NMR, and in some cases MS).