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1.
The nitro-imidazolines V and VI are formed by addition reaction of ethylenediamine to the isothiocyanates III and IV. The nitro group is then converted by hydrogenation to the amino group, giving XI and XII, which can be acylated selectively to IX and X. By rearrangement in boiling xylene, the compounds XI and XII give the corresponding 2-(2-aminoethylamino)-benzimidazoles XIII and XIV. The benzoylated derivative IX gives the benzimidazole derivative XVIII by rearrangement and subsequent migration of the benzoyl group, while the benzylated derivative XVI gives the rearranged benzimidazole XXII. The benzimidazole structure of the rearranged products is proven by unambiguous synthesis of XIII, starting with 2-chlorobenzimidazole (VII) and mono-N-acetyl-ethylene-diamine to give compound VIII, from which XIII is obtained by hydrolysis.  相似文献   

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Complexes of Vanadium and Titanium with 2,2′-Dihydroxyazobenzene. Crystal Structure of 2,2′-Dihydroxybenzenato(2-)-oxo-methoxo-methanol-vanadium(V) and μ-Oxo-bis[2,2′-dihydroxyazobenzenato(2-)-oxo-vanadium(V)] By the reaction of 2,2-dihydroxyazobenzene with titanium(IV) the expected compound bis [2,2′-dihydroxybenzenato(2-)-titanium(IV)] was obtained. On the other hand in the dependence on the experimental conditions vanadium forms further compounds beside the bisligand complex. They were characterized by mass spectrometry resp. X-ray structural analysis. Crystallographic data see ?Inhaltsübersicht”?.  相似文献   

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Base Catalysed Cyclizations of 2-(2-Propynyl)oxy-benzamide Systems 2-(2-Propynyl)oxy-benzamides were cyclized under base catalysis to 6- or 7-membered ring compounds, depending on the reaction conditions. Treatment of 2-(2-propynyl)oxy-benzamide ( 10 ) with sodium methylsulfinylmethanide (NaMSM) in DMSO gave two isomeric oxazepinons 11 (34%) and 12 (7%), while the transformation with sodium-2-propanolate in 2-propanol afforded the oxazinone 13 (34%) and with lithium cyclohexyl-isopropylamide (Li-CHIP) in N-methylpyrrolidone 11 (48%) exclusively (Scheme 4). N-Methyl-2-(2-propynyl)-oxy-benzamide ( 14 ) behaved similarly. In the reaction of 14 with sodium 2-propanolate in 2-propanol yielding the benzoxazinone 16 , the allenyloxy-benzamide 17 could be isolated as an intermediate (Scheme 5). The N-phenyl-compounds 18 and 22 treated with NaMSM/DMSO were converted to 3-anilino-2-methyl-benzo- and naphtho-pyran-4-ones, respectively (Schemes 6 and 7). The mechanisms for these reactions are discussed (Schemes 8, 9 and 10).  相似文献   

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Nucleotides. IX. Synthesis and properties of 1-(2′-deoxy-D -ribofuranosyl)-lumazin-3′-monophosphates The synthesis of various 1-(2′-deoxy-α-[and β-]D -ribofuranosyl)-lumazine-3′-monophosphates 25--30 starting from the corresponding pteridine nucleosides 1--6 is described. Monomethoxytritylation in 5′-position to 7--12 , phosphorylation by cyanoethylphosphate to 13--18 , and deprotection by acid and base treatment afforded the lumazine nucleotides 25--30 in good overall yield. The various reaction products have been characterized by physical means, such as UV. spectra, pK-values and their chromatographical and electrophoretical behaviour. Enzymatic dephosphorylations by alkaline phosphatase led to the starting material 1--6 with a 3--4 times slower hydrolysis rate in comparison to Tp.  相似文献   

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Nucleosides and Nucleotides. Part 10. Synthesis of Thymidylyl-(3′-5′)-thymidylyl-(3′-5′)-1-(2′-deoxy-β-D - ribofuranosyl)-2(1 H)-pyridone The synthesis of 5′-O-monomethoxytritylthymidylyl-(3′-5′)-thymidylyl-(3′-5′)-1-(2′-deoxy-β-D -ribofuranosyl)-2(1H)-pyridone ((MeOTr)TdpTdp∏d, 5 ) and of thymidylyl-(3′-5′)-thymidylyl-(3′-5′)-1-(2′-deoxy-β-D -ribofuranosyl)-2(1 H)-pyridone (TdpTdp∏d, 11 ) by condensing (MeOTr) TdpTd ( 3 ) and p∏d(Ac) ( 4 ) in the presence of DCC in abs. pyridine is described. Condensation of (MeOTr) TdpTdp ( 6 ) with Πd(Ac) ( 7 ) did not yield the desired product 5 because compound 6 formed the 3′-pyrophosphate. The removal of the acetyl- and p-methoxytrityl protecting group was effected by treatment with conc. ammonia solution at room temperature, and acetic acid/pyridine 7 : 3 at 100°, respectively. Enzymatic degradation of the trinucleoside diphosphate 11 with phosphodiesterase I and II yielded Td, pTd and p∏d, Tdp and Πd, respectively, in correct ratios.  相似文献   

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Nucleosides and Nucleotides. Part 16. The Behaviour of 1-(2′-Deoxy-β-D -ribofuranosyl)-2(1H)-pyrimidinone-5′-triphosphate, 1-(2′-Deoxy-β-D -ribofuranosyl-2(1H))-pyridinone-5′-triphosphate and 4-Amino-1-(2′-desoxy-β-D -ribofuranosyl)-2(1H)-pyridinone-5′-triphosphate towards DNA Polymerase The behaviour of nucleotide base analogs in the DNA synthesis in vitro was studied. The investigated nucleoside-5′-triphosphates 1-(2′-deoxy-β-D -ribofuranosyl)-2(1 H)-pyrimidinone-5′-triphosphate (pppMd), 1-(2′-deoxy-β-D -ribofuranosyl)-2(1 H)-pyridinone-5′-triphosphate (pppIId) and 4-amino-1-(2′-deoxy-β-D -ribofuranosyl)-2(1 H)-pyridinone-5′-triphosphate (pppZd) can be considered to be analogs of 2′-deoxy-cytidine-5′-triphosphate. However, their ability to undergo base pairing to the complementary guanine is decreased. When pppMd, pppIId or pppZd are substituted for pppCd in the enzymatic synthesis of DNA by DNA polymerase no incorporation of these analogs is observed. They exhibit only a weak inhibition of the DNA synthesis. The mode of the inhibition is uncompetitive which shows that these nucleotide analogs cannot serve as substrates for the DNA polymerase.  相似文献   

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Reaction of tetramethylsuccinicdinitrile with methylmagnesium iodide in boiling toluene leads to the title compound 8 in 80–85% yield. The magnesium complex of 2-imino-3,3,4,4-tetramethyl-5-methylidene-pyrrolidine is shown to act as an intermediate.  相似文献   

13.
Vibrational Spectra of Complexes of Gold Trichloride with 2,2′-Dipyridne and 4,4′-Dipyridine, Dipyridine and 4,4′-Dipyridine By reaction of Au2Cl6 with 2,2′-Dipyridine and 4,4′-Dipyridine, respectively, the complexes [AuCl2(2,2′-Dipy)][AuCl4] (I) and [AuCl2(4,4′-Dipy)]Cl (II) are obtained. IR and Raman spectra show that (I) has a complex chelate structure, whereas (II) is polymeric with cis-configuration of the ligands.  相似文献   

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Nucleotides. X. Synthesis and properties of dinucleoside monophosphates with 2′-deoxyadenosine and 1-(2′-deoxy-β-D -ribofuranosyl)-lumazines as building blocks The synthesis of various dinucleoside monophosphates 16--20 consisting of 2′-deoxyadenosine and 1-(2′-deoxy-β-D -ribofuranosyl)-lumazines via the triester approach is described. The fully protected phosphotriesters 6--10 as well as the partially deblocked intermediates 11--15 have also been isolated and characterized by physical means. Intramolecular interactions in 16--20 have been investigated by the determination of the hypochromicities and CD. spectra revealing a more or less distinct stacking effect in dependence of the 6,7-substituents in the lumazine moiety as well as the polarity of the internucleotidic linkage. Enzymatic degradations of the dinucleoside monophosphates with snake venom and spleen phosphodiesterase are depending strongly on various structural features indicating a much lower substrate specificity especially in presence of 6,7-diphenyl-lumazine as an aglycone with the latter enzyme.  相似文献   

15.
Complexes of Vanadium and Titanium with Salicylaldehyde benzoylhydrazone and 2-(2′-Hydroxyphenyl)-8-quinolinol. Crystal Structure of μ-Oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinato(2-)}-vanadium(V)] . By reaction of titanium(IV)-isopropoxide and bis(acetylacetonato)-oxovanadium(IV) with salicylaldehyde benzoylhydrazone and 2-(2′hydroxyphenyl)-8-quinolinol, respectively, the metal complexes of the tridentate diacidic ligands were synthesized and characterized mass spectrometrically. The mass spectra of the titanium compounds correspond to the expected bisligand complexes whereas several species are demonstrable in the case of vanadium. Crystals of μ-oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinolato(2-)}-vanadium(V)] were isolated and characterized by X-ray structural analysis. The complex exhibits C2 symmetry, accordingly the μ2-oxygen atom is situated on the 4 axis. The VOV bridge is angular with the unusually small bond angle of 107.3°. The coordination polyhedron is distorted octahedral. The compound additionally contains one molecule of chloroform per formula unit which is disordered in two positions. Crystallographic data see “Inhaltsübersicht”.  相似文献   

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Isomerization at the Complexation of 3-Acetyltetramic Acid: Structure and Magnetic Properties of the CuII- and NiII-Complex of 2,7-Bis (1′, 5′, 5′ -trimethylpyrrolidin-2′,4′ -dion-3′ -yl)-3,6-diazaocta-2,6-dien 2,7-Bis(1′, 5′, 5′ -trimethylpyrrolidin-2′, 4′ -dion-3′ -yl)-3,6-diazaoctadien formes CuII and NiII complexes with different constitutions (because of the Z/E isomerization). Results of X-ray analysis of N,N′ -ethylenbis(1′, 5′, 5′ -trimethylpyrrolidin-2′, 4′ -dion-3′ -acetiminato)nickel(II) 1 respectively -copper(II) 2 shows, that the complexing agent in 1 occurs in the E-form, whereas the ligand of the CuII complex forms the Z-form. Magnetic susceptibility and shift effects of the 13C-NMR signals point to a weak paramagnetism of the NiII complex. ESR-spectra are obtained from 2 only. Furthermore, the CuII complex reduces the relaxation times T1 and T2 of 1H and 17O nuclei spins from water. From the temperature dependence of the shortening of the relaxation times an activation energy is calculated which describes the reorientation of the copper complex in the “water matrix”.  相似文献   

18.
Synthesis of (R)-β, β-Caroten-2-ol and (2R, 2′R)-β, β-Carotene-2,2′-diol Starting from geraniol, the two carotenoids (R)-β, β-caroten-2-ol ( 1 ) and (2R, 2′R)-β, β-carotene-2,2′-diol ( 3 ) were synthesized. The optically active cyclic building block was obtained by an acid-catalysed cyclisation of the epoxide (R)- 4 . The enantiomeric excess of the product was > 95 %.  相似文献   

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