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Synthesis and Structure Elucidation of Merucathinone and Synthesis of Cathinone. Constituents of Catha edulis FORSK . Starting from L-alanine, two constituents of Catha edulis FORSK ., (S)-4-amino-1-phenylpent-1-en-3-on ((S)- 3 ; merucathinone) and (S)-2-amino-1-phenylpropan-1-on ((S)- 1 ; cathinone) were synthesized.  相似文献   

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The Isolation and Structural Elucidation of Microline. The structure and absolute configuration of microline, a new metabolite isolated from culture filtrates of Gilmaniella humicola BARRON , has been shown to be 1 , by spectral data and chemical transformations, and by X-ray analysis [4].  相似文献   

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Synthesis and Structure Elucidation of Merucathine and Pseudomerucathine. Two Constituents of Catha edulis FORSK . Starting from L-alanine, two constituents of Catha edulis FORSK . (3R,4S)-4-amino-1-phenyl-1-penten-3-ol ((3R,4S)- 4 , merucathine) and (3S,4S)-4-amino-1-phenyl-1-penten-3-ol ((3S,4S)- 4 , pseudomerucathine) were synthesized.  相似文献   

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Reactions of Zinc and Cadmium Halides with Tris(trimethylsilyl)phosphane and Tris(trimethylsilyl)arsane ZnCl2 reacts with E(SiMe3)3 (E = P, As) in toluene in the presence of PnPr3 to give the binuclear complexes [Zn2Cl2{E(SiMe3)2}2(PnPr3)2] · C7H8 (E = P 1 , As 2 ). Therefore by the use of PiPr3 clusters consisting of ten metal atoms are obtained, [Zn10Cl12(ESiMe3)4(PiPr3)4] (E = P 3 , As 4 ). As a result of the reaction of CdBr2 with P(SiMe3)3 the compound [CdBr2{P(SiMe3)3}]2 ( 5 ) can be isolated at –40 °C. In the presence of PnPr3 CdBr2 reacts with P(SiMe3)3 forming the binuclear complex [Cd2Br2{P(SiMe3)2}2(PnPr3)2] · thf ( 6 ). The same reaction with PiPr3 yields to the cluster [Cd10Br12(PSiMe3)4{P(SiMe3)3}4] · 2 C7H8 ( 7 ). ZnI2 and CdI2 react with As(SiMe3)3 to yield the complexes [MI2{As(SiMe3)3}]2 (M = Zn 8 , Cd 9 ). In the case of CdI2 additionally the cluster [Cd10I12(AsSiMe3)4 · {As(SiMe3)3}4] · 4,5 C7H8 ( 10 ) is formed which is analogous to the compounds 3 , 4 and 7 . In the presence of [PnBu4]I 8  reacts in THF to give the ionic compound [PnBu4]2[Zn6I6(AsSiMe3)4(thf)2] · C6H6 ( 11 ).  相似文献   

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The reactions of 4N‐ethyl‐2‐[1‐(pyrrol‐2‐yl)methylidene(hydrazine carbothioamide ( 4 EL1 ) and 4N‐ethyl‐2[1‐(pyrrol‐2‐yl)ethylidene(hydrazine carbothioamide ( 4 EL2 ) with Group 12 metal halides afforded complexes of types [M(L)2X2] (M = Zn, Cd; L = 4 EL1, 4 EL2; X = Cl, Br, I; 1 – 6 , 14 – 19 ) and [M(L)X2] (M = Hg; L = 4 EL1, 4 EL2; X = Cl, Br, I; 7 – 9 , 20 – 22 ). In addition, reaction of 4 EL1 with salts of CuII, NiII, PdII and PtII afforded compounds of type [M(4 EL1–H)2] ( 10 – 13 ). The new compounds were characterized by elemental analysis, FAB mass spectrometry, IR and electronic spectroscopy and, for sufficiently soluble compounds, 1H, 13C and, when appropriate, 113Cd or 199Hg NMR spectrometry. The spectral data suggest that in their complexes with Group 12 metal cations, both thiosemicarbazones are neutral and S‐monodentate; and for [Zn(4 EL1)2I2] ( 3 ), [Cd(4 EL1)2Br2] ( 5 ) and [Hg(4 EL1)Cl2]2 ( 7 ) this was confirmed by X‐ray diffractometry. By contrast, in its complexes with CuII and Group 10 metal cations, 4 EL1 is monodeprotonated and S,N‐bidentate, as was confirmed by X‐ray diffractometry for [Ni(4 EL1–H)2] ( 11 ) and [Pd(4 EL1–H)2] ( 12 ).  相似文献   

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Metabolites of Microorganisms. 216. Isolation, Structure and Synthesis of Ferrioxamine H The structure of ferrioxamine H , a minor component of the sideramine complex of actinomycetes, was determined by spectroscopic investigations, degradation and synthesis. Ferrioxamine H is the Fe (III)-complex of 11,22-dihydroxy-4, 12, 15, 23-tetraoxo-5,11,16,22-tetraazatetracosanoic acid ( 2 ).  相似文献   

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Alkali Metal Tetraethinylozincates and ‐cadmates AI2M(C2H)4 (AI = Na — Cs, M = Zn, Cd): Synthesis, Crystal Structures, and Spectroscopic Properties By reaction of AIC2H (AI = Na — Cs) with divalent zinc and cadmium salts in liquid ammonia the alkali metal tetraethinylozincates and ‐cadmates AI2M(C2H)4 (M = Zn, Cd) were accessible as polycrystalline powders. While Na2M(C2H)4 is amorphous to X‐rays and the crystal structure of Cs2Zn(C2H)4 could not be solved up to now, the remaining compounds are isotypic to the already known crystal structures of the potassium compounds, as was deduced from powder diffraction with X‐rays and synchrotron radiation. They crystallise in the tetragonal space group I41a, contain [M(C2H)4]2— tetrahedra and show structural relationships to the scheelit and anatas structure types. Raman spectroscopic investigations confirm the existence of tetrahedral fragments with C‐C triple bonds in the alkali as well as in the amorphous alkaline earth metal compounds AIIM(C2H)4 (AII = Mg — Ba, M = Zn, Cd).  相似文献   

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The 13C NMR spectra of some polysaccharides and their methyl derivatives have been analysed. The numbers and positions of the assigned 13C NMR signals give some information about the structure of the monomer unit and the positions of the glycosidic linkage but no information about the anomeric configuration. In this case the 1J(C-1, H) coupling constants make it possible to identify the anomeric configuration, because the mean differences of the J values for the α- and β-anomers are 12 Hz (at least 5 Hz) with the higher values for the α-anomers.  相似文献   

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Two coordination polymers, [Cd(Heidc)(bpp)]n ( 1 ) and [Zn3 (eidc)2(bpp)(H2O)2] · 2H2O}n ( 2 ) (H3eidc = 2‐ethyl‐4,5‐imidazole dicarboxylic acid, bpp = 1,3‐bis(4‐pyridyl)propane) were hydrothermally synthesized and characterized by elemental analysis, IR, spectroscopy single‐crystal X‐ray diffraction, and thermogravimetric analyses. Compound 1 features a 2D layer formed by C–H ··· π stacking interactions between adjacent chains, whereas compound 2 shows a 3D (83)2(85.10)‐tfc framework constructed of the 2D (6,3) layer. The result demonstrates that the central metal atoms play a key role in governing the coordination motifs. Moreover, solid‐state properties such as thermal stabilities and photoluminescence of 1 and 2 were also investigated.  相似文献   

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Synthesis and Crystal Structure of Manganese(II) and Zinc Amides, Mn(NH2)2 and Zn(NH2)2 Metal powders of manganese resp. zinc react with supercritical ammonia in autoclaves in the presence of a mineralizer Na2Mn(NH2)4 resp. Na2Zn(NH2)4_.0.5NH3 to well crystallized ruby‐red Mn(NH2)2 (p(NH3) = 100 bar, T = 130°C, 10 d) resp. colourless Zn(NH2)2 (p(NH3) = 3.8 kbar, T = 250°C, 60 d). The structures including all H‐positions were solved by x‐ray single crystal data: Mn(NH2)2: I41/acd, Z = 32, a = 10.185(6) Å, c = 20.349(7) Å, N(Fo) with F > 3σ (F) = 313, N(parameter) = 45, R/Rw = 0.038/0.043. Zn(NH2)2: I41/acd, Z = 32, a = 9.973(3) Å, c = 19.644(5) Å, N(Fo) with F > 3σ (F) = 489, N(parameter) = 45, R/Rw = 0.038/0.043. Both compounds crystallize isotypic with Mg(NH2)2 [1] resp. Be(NH2)2 [2]. Nitrogen of the amide ions is distorted cubic close packed. One quarter of tetrahedral voids is occupied by Mn2+‐ resp. Zn2+‐ions in such an ordered way that units M4(NH2)6(NH2)4/2 occur. The H‐atoms of the anions have such an orientation that the distance to neighboured cations is optimum.  相似文献   

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