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901.
Victor Mamane Frédéric Louërat Julien Iehl Mohamed Abboud Yves Fort 《Tetrahedron》2008,64(47):10699-10705
A new, short and efficient synthesis of substituted benzo-(iso)quinoline derivatives is reported. The methodology is based on a Suzuki or Negishi cross-coupling followed by a cyclization reaction induced by t-BuOK in DMF to form the central ring. This approach allowed the synthesis of all four benzo-(iso)quinoline isomers and the substitution of each ring of the benzo-(iso)quinoline core. 相似文献
902.
Mohamed E Abdul-Rahman PS Doustjalali SR Chen Y Lim BK Omar SZ Bustam AZ Singh VA Mohd-Taib NA Yip CH Hashim OH 《Electrophoresis》2008,29(12):2645-2650
A 35 kDa glycoprotein whose abundance was previously demonstrated to be enhanced in sera of patients with endometrial adenocarcinoma (n = 12), was isolated from pooled sera of three of the cancer patients using champedak galactose-binding lectin affinity chromatography in the present study. Subjecting it to 2-DE and MS/MS, the glycoprotein was identified as the O-glycosylated fragment of inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4). When compared to control sera (n = 17), expression of the 35 kDa ITIH4 cleavage fragment was demonstrated to be significantly enhanced in sera of patients with breast carcinoma (n = 10), epithelial ovarian carcinoma (n = 10), and germ cell ovarian carcinoma (n = 10) but not in patients with nasopharyngeal carcinoma (n = 13) and osteosarcoma (n = 7). The lectin-based electrophoretic bioanalytical method adopted in the present study may be used to assess the physiological relevance of ITIH4 fragmentation and its correlation with different malignancies, their stages and progression. 相似文献
903.
Al-Dirbashi OY Rashed MS Jacob M Al-Ahaideb LY Al-Amoudi M Rahbeeni Z Al-Sayed MM Al-Hassnan Z Al-Owain M Al-Zeidan H 《Biomedical chromatography : BMC》2008,22(11):1181-1185
We describe an improved diagnostic method for tyrosinemia type 1 based on quantifying succinylacetone in dried blood spots by ultra-performance liquid chromatography tandem mass spectrometry. Succinylacetone extracted from a single 3/16 inch disk of specimen collection paper containing a dried blood spot was derivatized with dansylhydrazine, separated on an Acquity UPLC BEH C(18) column (2.1 x 50 mm, 1.7 microm) and detected by electrospray ionization tandem mass spectrometry. Succinylacetone derivative eluted at 0.6 min with a complete run time of 1 min. Using a 13C4 labeled succinylacetone as an internal standard, the calibration plot was linear up to 100 micromol/L with a detection limit (S/N = 3) of 0.2 micromol/L. Intra-day (n = 13) and inter-day (n = 10) variations were better than 10%. The cutoff level of succinylacetone in dried blood spots from healthy infants obtained by the current method was 0.63 micromol/L (n = 151). In dried blood spots from patients with established tyrosinemia type 1 (n = 11), concentration of succinylacetone was 6.4-30.8 micromol/L. 相似文献
904.
Sayed M. Riyadh Hamad M. Al‐Matar Mohamed H. Elnagdi 《Journal of heterocyclic chemistry》2008,45(4):975-979
The utilization of arylhydrazononitriles ( 6‐9 ) for synthesis of azoles is demonstrated. Thus, arylazomalononitriles ( 6 ) reacted with hydroxylamine hydrochloride to afford isoxazol‐5‐imine ( 10 ), amidoxime ( 12 ) and bis‐amidoxime ( 13 ) derivatives depending upon both the reaction conditions and molar ratio employed. 2‐Thiazolyl‐2‐arylhydrazononitriles ( 7 ) and cyanoformazans ( 8 ) gave 1,2,3‐triazole derivatives ( 15 ) and ( 17 ) respectively upon treatment with hydroxylamine hydrochloride and concomitant loss of water molecule. Formation of novel 1,2,4‐triazin‐5(4H)‐one derivatives ( 21 ) has efficiently been carried out by treatment of amidoximes ( 18 ) with acetic anhydride in acetic acid. 相似文献
905.
Ramadan Ahmed Mekheimer Afaf Mohamed Abd El‐Hameid Kamal U. Sadek 《Journal of heterocyclic chemistry》2008,45(1):97-101
Reacting of 6‐azidopyridone derivatives 1 with o‐phenylenediamine ( 2a ) in chloroform at room temperature afforded the new azidopyridones 3 . However, its fusion with 2a,b at 100–110°C gave the interesting pyrido[2,3‐b][1,5]diazepines 4a,b . Alternatively, compound 4a could also be obtained by heating azidopyridones 3 at 100–110°C. When compound 1 was allowed to react with hydrazines 7a‐d at room temperature it gave the corresponding azido compounds 8a‐d . Fusion of 1 with phenylhydrazine ( 7d ) at 140–160°C afforded the new aminopyridones 10 . The 6‐azidopyridones 1 could also be converted to the corresponding 6‐alkylaminopyridones 15a‐d by reaction with an excess of alkylamines at room temperature. 相似文献
906.
Treatment of 2‐cyano‐3‐phenyl‐2‐pentenedinitrile with some heterocyclic diazonium salts afforded the corresponding heterocyclic hydrazones. Some of the latter hydrazones were converted into fused polyaza‐heterocycles upon boiling in pyridine. Reaction of 2‐cyano‐3‐phenyl‐2‐pentenedinitrile with phenylisothiocyanate gave a tricyano‐thiole derivative which on treatment with hydrazonoyl chlorides and 1‐(benzothiazol‐2‐yl)‐2‐bromoethanone furnished 1,3,4‐thiadiazole and thiazole derivatives, respectively. 相似文献
907.
Mohamed. R. Aouad Nadje T. Rezki El Sayed H. El Ahsry 《Journal of heterocyclic chemistry》2008,45(5):1321-1327
A solid support under microwave (MW) irradiation without solvent allowed the synthesis of the 2,3‐epoxy‐propyl‐thioimidazole 4 , regioselectively, and prohibited its cyclization to give the imidazo[2,1‐b]thiazine 3 from the reaction of 4,5‐diphenylimidazole‐2‐thione ( 1 ) with 1‐chloro‐2,3‐epoxy‐propane ( 2 ). The formation of the latter required basic conditions whereby it became the sole product; the change of the basic catalyst changed the ratio of the two products under both conventional and microwave (MW) conditions. A regioselective allylation of 1 with allyl bromide in presence of triethylamine gave the S‐allyl 8 , while in presence of potassium carbonate led to the S,N‐bis(allylated) derivative 9 . The intramolecular ring closure of 8 in presence of sulfuric acid afforded the imidazothiazole 16 . Protection of the sulfur in 1 and subsequent reaction with allyl bromide gave the N‐allylated derivative and with 2 gave N‐3‐chloro‐prop‐1‐yl derivative that shed light on the preferred route for the formation of 3 and 4 . The reactivity encountered during the alkylation of 1 with 2 has been theoretically investigated by using the AM1 method. 相似文献
908.
Saleh M. Al‐Mousawi Morsy A. El‐Apasery Najat Al‐Kandery Mohamed H. Elnagdi 《Journal of heterocyclic chemistry》2008,45(2):359-364
1‐[2‐Phenyl‐1‐diazenyl]‐1‐[2‐phenylhydrazono]acetone or 1‐[‐2‐(4‐methylphenyl)‐1‐diazenyl]‐1‐[‐2‐(4‐methylphenyl)hydrazono]‐butan‐2‐one were produced via coupling the (E) 2‐oxopropanal‐1‐phenyl‐hydrazone or (E) 2‐oxobutanal‐1‐(4‐methylphenyl)hydrazone with aromatic diazonium salts. These formazanes condensed readily with ethyl cyanoacetate to yield 5‐methyl‐3‐oxo‐2‐phenyl‐6‐phenylazo‐2,3‐dihydropyridazine‐4‐carbonitrile compound ( 9a ), 5‐ethyl‐3‐oxo‐2‐p‐tolyl‐6‐p‐tolylazo‐2,3‐dihydro‐pyridazine‐4‐carbonitrile and/or 5‐ethyl‐3‐oxo‐2,6‐di‐p‐tolyl‐2,3‐dihydropyridazine‐4‐carbonitrile that reacted with sulphur in presence of piperidine to yield the aminothienopyridazinones. The latter reacted with electron poor olefins and acetylenes to yield aminophthalazines. Compound ( 9a ) reacted also with benzylidenemalononitrile to yield the arylazophthalazinone. 相似文献
909.
Mohamed Ghazzali Vratislav Langer Lars Öhrström 《Journal of solid state chemistry》2008,181(9):2191-2198
Two new dual-metal assemblies: 2[Ru(phen)3]2+·[Fe(SCN)4]2−·2SCN−·4H2O 1 and [Ru(phen)3]2+·[Co(SCN)4]2−2, (phen:1,10-phenanthroline), have been prepared and their structures were characterized by X-ray diffraction. In 1, the cationic octahedral enantiomers are arranged with a ΛΔΛΔΛ sequence supported by π-π stacking and the anionic inorganic tetrahedral units are oriented between these stacks by interacting with the nearby water molecules through strong O-H?O and O-H?S hydrogen bonds. In 2, homochiral double helices in the b-direction are revealed, with tetrakis-isothiocyanate CoII anions arranged in the crystal to furnish one-dimensional (1D)-helical chains with S?S intermolecular interactions at 3.512(2) and 3.966(2) Å supporting [Ru(phen)3]2+Λ- and Δ-helices with Ru?Ru shortest distance of 8.676(7) Å. In both 1 and 2, the supramolecular assembly is maintained by C-H?S hydrogen bonds extending between the phenanthroline aromatic carbons in the cationic nodes and the sulphur atoms of the isothiocyanates anions. Analysis of S?S interactions in isothiocyanate containing compounds using Cambridge structural database (CSD) showed an angle dependence categorizing these interactions into “type-I” and “type-II”. 相似文献
910.
Somnath Roy Tarak Nath Mandal Anil Kumar Barik Samik Gupta Ray J. Butcher Mohamed Salah El Fallah Javier Tercero Susanta Kumar Kar 《Polyhedron》2008
The synthesis and structure of a pyrazole-based orthogonal ferromagnetically coupled tetracopper(II) 2 × 2 homoleptic grid complex [Cu4(PzOAPyz)4(ClO4)2](ClO4)2 · 6H2O (1), formed by the reaction between the ditopic ligand PzOAPyz and Cu(ClO4)2 · 6H2O, are described. The ligand contains terminal pyrazole and pyrazine residues bound to a central flexible diazine subunit (N–N) as well as one potentially bridging alkoxo group. The two adjacent metal centers are linked by an alkoxo oxygen forming essentially a square Cu4(μ-O4) cluster. In the Cu4(μ-O4) core, out of the four copper centers, two copper centers are penta-coordinated and the remaining two are hexa-coordinated. In each case of hexa-coordination, the sixth position is occupied by one of the oxygen atoms of a coordinated perchlorate ion. Complex 1 has been characterized structurally and magnetically. Although the large Cu–O–Cu bridge angles (137–138°) and short Cu–Cu distances (3.964–3.970 Å) are suitable for the transmission of the expected antiferromagnetic coupling, the square-based Cu4(μ-O4) cluster exhibits an intramolecular ferromagnetic exchange (J = 7.47 cm−1) between the metal centers with an S = 2 magnetic ground state associated with the quasi orthogonal arrangement of the magnetic orbitals (dx2-y2). The exchange pathway parameters have been evaluated from density functional calculations. 相似文献