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71.
Laurent CalculArlette Longeon Ali Al MourabitMichèle Guyot Marie-Lise Bourguet-Kondracki 《Tetrahedron》2003,59(34):6539-6544
Four novel alkaloids of the aaptamine class have been isolated in addition to the known aaptamine, isoaaptamine, demethyl(oxy)aaptamine and its dimethylketal from an unidentified species of Indonesian marine sponge of the genus Xestospongia. Their structures were elucidated on the basis of detailed 1D and 2D NMR spectroscopic data. Their antimicrobial activity was tested towards Gram (+) (S. aureus), Gram (−) (E. coli, V. anguillarum) bacterial strains, a fungus (C. tropicalis); their cytotoxic activity was evaluated against KB cells. 相似文献
72.
Reaction of 2-alkyl-4,5-dichloropyridazin-3(2H)-ones with p-cyanophenol and 2-mercaptopyrimidine in the presence of base gave 2,4,5-trisubstituted-pyridazin-3(2H)-ones 4-9, 2-(4-cyanophenoxy)pyrimidine (10) and 5-cyano-5-(pyrimidin-2-yl)-2,7-dialkyl-5H-dipyridazino[4,5-b:4,5-e]-4H-thiopyran-1,6-diones 11 as a novel heterocycle. 相似文献
73.
N. N. Smirnova K. V. Kandeev T. A. Bykova T. G. Kulagina A. M. Fainleib 《Russian Chemical Bulletin》2006,55(5):845-851
The temperature dependences of the heat capacity of partially crystalline linear polyurethanes based on 1,6-hexamethylenediisocyanate
with butane-1,4-diol and hexane-1,6-diol were studied for the first time in a temperature range of 6–460 K by the methods
of adiabatic vacuum and dynamic calorimetry. Physical changes in the state of polyurethanes were revealed and characterized;
the standard thermodynamic functions, namely, C
p
°(T), H°(T)-H°(0), S°(T), and G°(T)-H°(0), were calculated from the obtained experimental data in the temperature range from T → 0 to 460 K for the polymers in the crystalline, glassy, highly elastic, and liquid states. The energies of combustion of
the polymers were measured by the bomb calorimetry method, and the standard thermodynamic characteristics of their formation
at 298.15 K were calculated. The thermodynamic characteristics of bulk polycondensation of 1,6-hexamethylenediisocyanate with
butane-1,4-diol and hexane-1,6-diol to form linear aliphatic polyurethanes-{4,6} and-{6,6} were determined in the range from
T → 0 to 350 K at p° = 0.1 MPa. The thermodynamic properties of the polyurethanes under study and polymers of isomeric structure were compared.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 817–823, May, 2006. 相似文献
74.
2-Trimethylsilylethinylated 1,6-methano[10]annulene1 a was obtained by reaction of 2-bromo-1,6-methano[10]annulene with trimethylsilylacetylene in the presence of bis-(triphenylphosphin-)-Pd (II) chloride and Cu(I) and also by reaction of 1,1-diiodo-2-(1,6-methano[10]annulene-2-yl)-ethene (2) withn-buthyl-lithium followed by hydrolysis.1 a reacts with 2N NaOH to 2-ethinyl-1,6-methano[10]annulene (1 b). 2,7- and 2,10-dibromo-1,6-methano[10]annulene can be substituted to give the trimethylsilylethinylated compounds3 a–6 a, which then can be transformed with 2N NaOH into the desilylated products3 b–5 b.
Wolfgang Kraus, Stuttgart-Hohenheim, mit den besten Wünschen in Freundschaft zum 60. Geburtstag gewidmet 相似文献
75.
N-Methyl-2-benzoylmethylsulfanyl-4-phenylnicotinamide and N-methyl-2-(4-phenyl-1,3-thiazol-2-yl)-acetamide have been obtained
as alternative products to the desired N-methyl-2,3-dihydro-7H-thiazolo[3,2-a]pyridine-8-carboxamide by a one-pot cyclocondensation
of benzylidenemalononitrile, N-methyl-2-thiocarbamoylacetamide, piperidine, and ω-bromoacetophenone. 2-Amino-1-methyl-6-oxo-4-phenyl-5-(4-phenyl-1,3-thiazol-2-yl)-1,6-dihydropyridine-3-carbonitrile
has been obtained as main product by treatment of benzylidenemalononitrile with N-methyl-2-(1,3-thiazol-2-yl)acetamide.
Dedicated to Professor I. Kalvinsh on his 60th birthday
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 777–781, May, 2007. 相似文献
76.
A. Özbay S. Sağlam T.R. Sertbakan E. Kasap S. Özçelik 《Journal of inclusion phenomena and macrocyclic chemistry》2007,58(1-2):49-54
Infrared spectra of M(1,10-diaminodecane)Ni(CN)4 · 1,5 G (M=Co, Ni or Cd; G=o-xylene, m-xylene, p-xylene) and Cd(l,6-diaminohexane)M(CN)4 · C6H6 (M=Cd or Hg) clathrates are reported. The 1,10-diaminodecane and 1,6-diaminohexane molecules in the host permit the inclusion
of bulky guest molecules. The spectral data of clathrates were compared with those of the corresponding host. The spectral
features suggest that these compounds are similar in structure to other Hofmann-type and Hofmann-Td type clathrates, respectively. 相似文献
77.
Summary Syntheses of 1,6-methano[10]annulene-phthalimido-derivatives4,5 a,5 b,5 c, and6 are described, starting from 2,7-disubstituted 1,6-methano[10]annulenes; derivative8 was prepared from 2-bromo-11,11-difluoro-1,6-methano[10]annulene (9).4 and8 can be changed to the 2-amino-1,6-methano[10]annulenes10 and11.
Herrn Professor Siegfried Hünig, Würzburg, mit den besten Wünschen zum 70. Geburtstag gewidmet 相似文献
78.
The synthesis of various 2H-1,5-benzodioxepin and 2,5-dihydro-1,6-benzodioxocin derivatives is described. The key step involves the construction of seven- and eight-membered rings via ring-closing metathesis reaction. 相似文献
79.
Khmel'nitskaya E. Yu. Ivanov A. S. Tugusheva N. Z. Grigor'ev N. B. Granik V. G. 《Russian Chemical Bulletin》2003,52(5):1157-1160
The electroreduction of benzo[b][1,6]naphthyridine derivatives in anhydrous media by the polarographic method was studied. It is found that the first step of the process is the transfer of an electron to position 10 of the molecule, which is consistent with the addition of nucleophilic reagents to this particular position of the tricyclic system in question. 相似文献
80.