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991.
Zusammenfassung Es wird über die Synthese von verschiedenen methylsubstituiertens-Triazolo[4,3—b]pyridazinen berichtet. Außerdem wurdens-Triazolo[4,3—b]pyridazin und seine 7-Methyl- und 6-Chlor-Derivate der homolytischen Methylierung unterworfen, die Reaktionsgemische gaschromatographisch auf einzelne Methyl-s-triazolo[4,3—b]pyridazine aufgetrennt und die Verbindungen identifiziert.
Syntheses of pyridazines, XXVI: Synthesis and homolytic methylation of s-triazolo[4.3—b]pyridazines
The syntheses of some methyl substituteds-triazolo[4,3—b]-pyridazines are reported.s-Triazolo[4.3—b]pyridazine and its 7-methyl and 6-chloro analogs were submitted to homolytic methylations and the obtained reaction mixtures were separated by gas chromatography into particular components which were then identified.
  相似文献   
992.
Applied Biochemistry and Biotechnology - Z.mobilis (ATCC 29191) produced ethanol in significantly greater yield thanS. cerevisiae, (0.49 vs 0.45 g ethanol/g glucose entering the system), in...  相似文献   
993.
The Michael condensation of 1,1,2,2-tetracyanoethane with 3-methyl-4-benzylideneisoxazolin-5-one having the Z configuration leads to a heterocyclic spiran with retention of the cis orientation of the phenyl and keto groups. The deviations of the series of bond angles of the spiran from the standard values, the abnormal lengths of the C-C bonds adjacent to the gem-dicyano group, and the appearance of nonbonding >C=O(...)CN interactions and conjugation effects in the enaminonitrile fragment are discussed.For Communication 10, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1404–1410, October, 1988.  相似文献   
994.
995.
By allylation and benzylation of 2-phenyl- and 2-phenyl-3-formylindole, N-allyl- and benzyl-substituted indoles have been obtained. By condensation of 2-phenylindole with 2-formylfluorene, and also with 4-aza- or 3-methyl-2-azafluorenone, compounds containing fragments of the indole, fluorene, and azafluorenone systems have been synthesized. In the interaction of 2-phenylindole or indole with formaldehyde and 2,5-dimethylpiperidin-4-one, depending on the temperature, bis(2-phenylindol-3-yl)methane, (2,5-dimethyl-4-oxopiperidino)-(1-indolyl)methane, and bis(indol-3-yl)methane are formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 29, No. 5, pp. 648–650, May, 1993.  相似文献   
996.
By condensation of 6-methyl-3,4-dioxo-1H-furo[3,4-c]pyridine with heteroaromatic aldehydes, furfurylidene- and thenylidenefuropyridinediones have been obtained. By means of 1H NMR spectrometry using the nuclear Overhauser effect, it has been established that these compounds have the cis-s-cis and cis-s-trans conformations, respectively.For Communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 29, No. 5, pp. 633–638, May, 1993.  相似文献   
997.
Alizarin Red S. displays a dramatic change in fluorescence intensity and color in response to the binding of a boronic acid and can be used as a general reporter for studying carbohydrate-boronic acid interactions, both quantitatively and qualitatively.  相似文献   
998.
The split-root technique was used to study the effect of varying the growth media on the elemental content of nutrient elements in the roots of grape vines. The varieties 2-1 (R99 x Jacquez) and Sauvignon blanc (Vitis vinifera) were grown in Hoagland water culture with and without added aluminium. The elemental concentrations of Mg, Al, Si, P. S, Cl, K and Ca in the dried roots were determined by PIXE. Roots grown in Al-rich media were deficient in Mg and Ca, but enriched in Al. There was a correlation between Al and Si but the uptake differed in the two varieties.  相似文献   
999.
Laserspectroscopic investigations were performed on a collimated atomic beam of barium (natural isotope abundance). The metastable ground levels (3D1,2,3 and 1D2) of the investigated lines were populated by a discharge burning in barium vapour directly in front of the oven hole. We could investigate 14 spectral lines between 580 and 690 nm. The tensor polarizabilities of the upper and the lower level as well as the differences in the scalar polarizabilities could be determined. Spectra in magnetic fields up to 0.03 Tesla showed no deviation from the pattern resulting from a simple Russell-Sounders coupling.  相似文献   
1000.
The behavior of hexafluoroacetone ethoxycarbonylimine in cyclocondensation with different binucleophiles of the amidine type, viz., amino derivatives of N- and N,S-heterocycles, was studied. A preparative method for the synthesis of previously unknown annelated 2,2-bis(trifluoromethyl)-1,3,5-triazinones was developed.  相似文献   
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