Synthesis and Characterization of nido-[1,1,2,2-(CO)(4)-1,2-(PPh(3))(2)-1,2-FeIrB(2)H(5)]: A Heterobimetallaborane Analogue of nido-[B(4)H(7)](-)

The synthesis and characterization of nido-[1,1,2,2-(CO)(4)-1,2-(PPh(3))(2)-1,2-FeIrB(2)H(5)] (1) is reported. 1 is formed in low yield as a degradation product from the reaction between [{&mgr;-Fe(CO)(4)}B(6)H(9)](-) and trans-Ir(CO)Cl(PPh(3))(2) in THF and is characterized from NMR, IR, and analytical data and by a single-crystal X-ray diffraction study. 1 crystallizes in the monoclinic space group P2(1)/n with a = 12.8622(12), b = 14.3313(12), c = 23.579(3) ?, beta = 97.12(2) degrees, Z = 4, V = 4257.0(8) ?(3), R(1) = 4.83%, and wR(2)()(F(2)) = 12.43%. The heterobimetallaborane structure may be viewed as a derivative of the binary boron hydride nido-[B(4)H(7)](-) and is related to the known homobimetallatetraborane analogues [Fe(2)(CO)(6)B(2)H(6)] and [Co(2)(CO)(6)B(2)H(4)]. 1 exhibits proton fluxionality in its (1)H NMR spectrum, which is related to that found in the latter two compounds.     

Synthesis of 5-(Arylamino)-1-benzyluracils

The synthesis of novel 5-(phenylamino)-, 5-(benzylamino)-, and 5-(phenethylamino) derivatives of 1-benzyluracil-containing different substituents in the aromatic nucleus has been carried out. Using the Hilbert-Johnson reaction it was found that N₍₁₎-monosubstitution can be achieved via alkylation of trimethylsilyl derivatives of 5-(arylamino)uracils using benzyl bromide. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 887–892, June, 2005.     

The synthesis of 2-substituted azino-3-(β-D-ribofuranosyl)-5-carboxymethylenethiazolidin-4- ones

2-(1-Isopropylidene)azino-3-β-D-ribofuranosyl-5- methoxycarbonylmethylenethiazolidin-4-one (IV) and 2-(1-methylbenzilidene)azino-3-β-D-ribofuranosyl-5-carboxymethylenethiazolidin-4-one were prepared by independent synthesis utilizing either acid catalyzed fusion of 2-(1-isopropylidene)azino-5-methoxycarbonylmethylenethiazolidin-3(H)-4-one (II) with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose, silylation procedure with 2,3,5-tri-O-benzoyl-D-ribofuranosyl bromide or by cyclization of new isopropylidene and/or methylbenzilidene derivatives (VII) of 4-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)thiosemicarbazide (VI) with maleic anhydride and subsequent methylation. The synthetic approach has unambigously established the glycosilation site as well as anomeric configuration, which was additionally derived from pmr spectral data.     

Novel one-pot multicomponent synthesis of (E)-2-(benzylideneamino)-5-mercapto-4H-1,2,4-triazol-3-yl)-2,3-dihydrophthalazine-1,4-dione derivatives

Abstract

An expeditious, one-pot multicomponent reaction has been developed for the synthesis of (E)-2-(benzylideneamino)-5-mercapto-4H-1,2,4-triazol-3-yl)-2,3-dihydrophthalazine-1,4-dione derivatives. Condensation of 4-amino-5-hydrazino-4H-1,2,4-triazole-3-thiol with phthalic anhydride and aromatic aldehyde afforded the (E)-2-(benzylideneamino)-5-mercapto-4H-1,2,4-triazol-3-yl)-2,3-dihydrophthalazine-1,4-diones in acetic acid medium with excellent yields. All the synthesized compounds were characterized by their analytical and spectral data.     

1-(3,4-二甲氧基）苯乙基-3-环氧丙基-5-氰基-6-甲基脲嘧啶的合成及晶体结构

标题化合物1-（3，4-二甲氧基）苯乙基-3-环氧丙基-5-氰基-6-甲基脲嘧啶是 由1-（3，4-二甲氧基）苯乙基-5-氰基-6-甲基脲嘧啶在NaOH水溶液中与环氧氯丙 烷反应制得。结构通过单晶X射线衍射分析确定，其晶体属于单斜晶系，空间群 P2_1/a, 晶胞参数：a = 1.09(10) nm, b = 1.43(10) nm, c = 1.20(8) nm, V = 1.868 nm~3，Z = 4, D_c = 1.32 Mg/m~3, F(000) = 784。并用波谱法对分离得 到的副产物进行了结构表征。     

Crystal Structure and DFT Studies of a Triazole Derivative： 4- （ 2-Hydrobenzylideneamino ） -3- （ 1,2,4-triazol-4-ylmethyl） 1H-1, 2,4-triazole-5 （4H） -thione

A novel triazole derivative 4-(2-hydrobenzylideneamino)-3-(1,2,4-triazol-4-ylmethyl)-1H-1,2,4-triazole-5(4H)-thione(1) was synthesized and characterized using elemental analysis, FTIR, and 1H NMR, and its crystal structure was determined via X-ray single crystal diffraction analysis. Crystal data: monoclinic, P2(1)/c, a=0.83335(9) nm, b=1.49777(16) nm, c=1.14724(12) nm, β =107.990(2)°, D=1.470 Mg/m3, and Z=4. The geometries and the vibrational frequencies were determined using the density functional theory(DFT) method at the B3LYP/ 6-31G level. To demonstrate the accuracy of the reaction route of compound 1, one of the important intermediates was also tested using the same method. The structural parameters of the two compounds calculated using the DFT study are close to those of the crystals, and the harmonic vibrations of the two compounds computed via the DFT method are in good agreement with those in the observed IR spectral data. The thermodynamic properties of the title compound were calculated, and the compound shows a good structural stability at normal temperature. The test results of biological activities show that it has a certain bactericidal ability.     

Asymmetric synthesis of the putative structure of (-)-oryzoxymycin

[reaction: see text] A short asymmetric synthesis of (2'S,5R,6R)-2'-[6-amino-5-hydroxy-1,3-cyclohexadiene-1-carbonyloxy]propionic acid, the enantiomer of the reported structure of (+)-oryzoxymycin is described. The reported spectral data does not match that obtained for synthetic "oryzoxymycin".     

Structure of 1(5)-aryl-3-phenyl-5(1)-(2-benzothiazolyl)formazanes

1,3-Diphenyl-5-(2-benzothiazolyl)formazane exists in its crystalline state (based on x-ray crystal structure data) in the E ^1,2 Z ^2,3 Z ^3,4-conformation, which is stabilized by intramolecular hydrogen bonding (IMHB); the proton is localized on the nitrogen atom which is bound to the heterocycle. In chloroform solutions 1(5)-aryl-3-phenyl-5(1)-(2-benzothiazolyl)formazanes exist in the form of equilibrium mixtures of their chelate and open E ^1,2 Z ^2,3 Z ^3,4-forms, in which the first of these forms predominates. Based on their ¹³ C-NMR spectral data the tautomeric equilibrium involving these forms is shifted in favor of the benzothiazolylhydrazone form. The amount of tautomer containing the benzothiazolidene fragment structure increases in DMSO solution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1268–1274, September, 1991.     

Total synthesis of (-)-21-isopentenylpaxilline

[structure: see text] The total synthesis of (-)-21-isopentenylpaxilline (1) has been achieved. Key elements of the synthesis include the stereocontrolled construction of the advanced eastern hemisphere (-)-5, a highly efficient union of the eastern and western fragments (-)-5 and 4, respectively, exploiting our 2-substituted indole synthesis, and a new protocol for the construction of ring C.     

Inhaltsstoffe des Osmanthus-Absolues. 5. Mitteilung. (8E)-4, 7-Epoxymegastigma-5(11),8-dien

Constituents of Osmanthus absolute, 5th communication. (8 E )-4,7-Epoxymegastigma-5(11),8-diene The title compound 1 has been identified as trace constituent in Osmanthus absolute. The synthesis of 1 was performed by reaction of α-ionone-epoxide ( 4 ) with aluminum tri (isopropylate) in 2-propanol at 130°. Besides 1 we found another bicyclic ether 5 in the lower boiling part of the reaction mixture, and ten further substances with interesting structural features from the less volatile part. Formation mechanism as well as some spectral particularities are discussed in more detail.     

Novel,Simple, and Efficient Synthesis of 3-(2-(5-(Benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one Derivatives via a One-Pot,Four-Component Condensation Reaction

The synthesis of 3-(2-(5-(benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one derivatives was achieved through a one-pot, four-component reaction involving condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, thiosemicarbazide, phenacylcyanaide, and various aryl aldehydes in dry alcohol and few drops of acetic acid under reflux condition. This four-component reaction has some advantages such as ease of handling, good yields, and easy workup. All structures of newly prepared compounds were confirmed by analytical and spectral data.     

Synthesis and properties of 5-(5-nitro-2-furyl)thiazolines

The reactions of 2-amino-4-methyl-5-(5-nitro-2-furyl)thiazole with excess methyl iodide leads to 3,4-dimethyl-2-methylamino-5-(5-nitro-2-furyl)thiazolium iodide, which is converted to 2-imino-3,4-dimethyl-5-(5-nitro-2-furyl)thiazoline under the influence of bases. The iminothiazoline structure was proved by comparison of the spectral characteristics of its acetyl derivative and the isomeric 2-(N-acetyl-N-methyl) amino-4-methyl-5-(5-nitro-2-furyl)thiazole. The pKa values of 2-amino-4-methyl-5-(5-nitro-2-furyl)thiazole and 3,4-dimethyl-2-imino-5-(5-nitro-2-furyl)-thiazoline were determined, and the constant of the aminothiazole-iminothiazoline tautomeric equilibrium was calculated.Translated from Khimiya Geterosiklicheskikh Soedinenii, No. 10, pp. 1337–1340, October, 1985.     

Synthesis of 2′-[2-(5-benzyloxyindolyl)]propylamine derivatives

The synthesis of some 2′-[2-(5-benzyloxyindolyl)]propylamine derivatives 1–15 from 2-(5-benzyloxyindole)carboxyaldehyde ( 16 ) and 2-(5-benzyloxy-1-methylindole) carboxyaldehyde ( 17 ) is reported. Compounds 1–15 have been designed as potential monoamine oxidase A and B inhibitors.     

Synthesis of 5-polyfluoroalkyl-4-( p -tolyl-sulfonyl)pyrazoles and 4-polyfluoroalkyl-5-( p -tolylsulfonyl)pyrimidines from 1-dimethylamino-2-( p -tolylsulfonyl)-polyfluoro-1-alken-3-ones

1-Dimethylamino-2-(p-tolylsulfonyl)polyfluoro-1-alken-3-ones were obtained from hydrates of 3,3,3-trifluoro-1-(p-tolylsulfonyl)-2-propanone and 3,3,4,4,5,5-hexafluoro-1-(p-tolylsulfonyl)-2-pentanone under conditions of the Vilsmeier-Haack-Arnold reaction. The analogous reaction of 3,3-difluoro-1-(p-tolylsulfonyl)-2-propanone hydrate leads to 3-chloro-1-dimethylamino-4,4-difluoro-2-(p-tolylsulfonyl)-1,3-butadiene. The feasibility of using 1-dimethylamino-2-(p-tolylsulfonyl)-polyfluoro-1-alken-3-ones in reactions with nitrogen binucleophiles has been demonstrated for the regioselective synthesis of pyrazoles and pyrimidines. The structure of 1-phenyl-4-(p-tolylsulfonyl)-5-trifluoromethyl-1H-pyrazole was confirmed by X-ray diffraction structural analysis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1052–1058, July, 2007.     

Cu(II), Ni(II) and Fe(II) complexes with a new substituted [1,2,4] triazole Schiff base derived from 4-amino-5-(thien-2-yl ethyl)-2,4-dihydro-3H-1,2,4-triazol-3-one and 2-hydroxy-1-naphthaldehyde: synthesis,characterization and a comparison of theoretical and experimental results by Ab inito calculation

The synthesis and structural properties of two novel compounds, 4-amino-5-(thien-2-yl ethyl)-2,4-dihydro-3H-1,2,4-triazol-3-one and 4-{[(2-hydroxy-1-naphthyl)methyl-ene]amino}-5-(thien-2-ylmethyl) − 2,4-dihydro-3H-1,2,4-triazol-3-one have been described. 4-Amino-5-(thien-2-ylmethyl)-2,4-dihydro-3H-1,2,4-triazol-3-one was synthesized by treating N-propionyl-2-thien-2-ylethane-hydrazonoate with hydrazine hydrate and the Schiff base was obtained from condensation of substituted amine with 2-hydroxy-1-naphthaldehyde. The Cu(II), Ni(II) and Fe(II) complexes were prepared and characterized by elemental analyses, IR, magnetic moment, UV–Vis, mass spectral data and ¹H- and ¹³C-NMR IR spectra. The Schiff base is coordinated to the metal ions in a tridentate manner with OON donors of the phenolic O, carbonyl O and triazolic N. From the magnetic and UV spectral data, it was found the geometrical structure of Cu(II) and Fe(II) ions are octahedral while Ni(II) ion is square planar.Ab-inito 6-31 G* level calculations provided structural information and IR data that were in good agreement with experimental results.     

Possibility of intramolecular hydrogen bonding in 1-[β-(2-pyridyl)ethyl]-5-amino(or hydroxy) pyrazoles

It is shown on the basis of IR spectral and dipole moment data that the formation of a seven-membered cyclic structure is possible in 1-[-(2-pyridyl)ethyl]-5-amino(or hydroxy)-pyrazoles, stabilized by intramolecular hydrogen bonds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1255–1257, September, 1970.     

1-(4-硝基苯基)-3-(5-溴吡啶)-三氮烯的合成及其与镉(Ⅱ)离子的显色反应

报道了 1 (4 硝基苯基) 3 (5 溴吡啶)三氮烯(NPBPDT)的合成及其与镉的显色反应.在TritonX 100的存在下,该试剂能与镉发生显色反应,形成摩尔比为 2∶1型的黄色配合物,在 440nm处有一最大正吸收峰,在540nm处有一最大负吸收峰.以 440nm为参比波长, 540nm为测量波长进行双波长测定,表观摩尔吸光系数为3. 14×105 L·mol-1·cm-1,镉的浓度在 0~0. 48mg/L范围内遵守比尔定律.用拟定方法测定废水中的微量镉,结果满意.     

Synthesis of 3-[4-(1-Benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one Derivatives as Biological Agents

A protocol for the synthesis of 3-[4-(1-benzofuran-2-yl)-1,3-thiazol-2-yl]-2-(4-aryl)-1,3-thiazolidin-4-one derivatives (5a–e) has been developed from 1-(1-benzofuran-2-yl)-2-bromoethanone (2),which served as a key intermediate for the synthesis of the title compounds. The reaction of compound 2 with thiourea furnished 4-(1-benzofuran-2-yl)-1,3-thiazol-2-amine 3, which upon further reaction with various aromatic aldehydes, gave Schiff bases 4a–e. These Schiff bases, when treated with thioacetic acid in the presence of catalytic amount of anhydrous ZnCl₂, yielded thiazolidinone derivatives 5a–e. All the newly synthesized compounds have been characterized by analytical and spectral data and screened for their antimicrobial and analgesic activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

A new route to the improved synthesis of 1-(alkoxymethyl)-5-alkyl-6-(arylselenenyl)uracils

A new route to C-6-selenenyl analogs of compound 1a from 5-alkyl-6-chlorouracils 6a-b has been described. A mild and highly efficient synthesis of 1-(alkoxymethyl)-5-alkyl-6-(arylselenenyl)uracils 8a-e has been accomplished from 6a-b in good yields using a two step procedure. Silylation of 5-alkyl-6-chlorouracils 6a-b using N,O-bis(trimethylsilyl)acetamide followed by regioselective alkylation of the silylated intermediate with ethyl or benzyl chloromethyl ether in dichloromethane afforded the desired 1-(alkoxymethyl)-5-alkyl-6-chlorouracils 7a-d in 88–94% yields. Compounds 7a-d readily underwent addition-elimination reaction with an appropriate arylselenol in the presence of ethanolic sodium hyroxide to produce the corresponding 1-(alkoxymethyl)-5-alkyl-6-(arylselenenyl)uracils 8a-e in excellent yields (94–99%).     

Chemoenzymatic synthesis of (5S)- and (5R)-hydroxymethyl-3,5-dimethyl-4-(methoxymethoxy)-5H-thiophen-2-one: a precursor of thiolactomycin and determination of its absolute configuration

A convenient enantioselective synthesis of (5S)- and (5R)-hydroxymethyl-3,5-dimethyl-4-(methoxymethoxy)-5H-thiophen-2-one, a key intermediate in the synthesis of thiolactomycin has been carried out by a Carica papaya lipase-mediated resolution protocol to provide (R)-2 in a 94% ee and its enantiomer (S)-9 in a 98% ee. The absolute configuration at the C-5 position has been determined by Mosher’s method.