Some condensation products of ergoline - I Derivatives with ketones

1980 ◽  
Vol 45 (3) ◽  
pp. 755-760 ◽  
Author(s):  
Jiří Křepelka ◽  
Jiří Holubek ◽  
Miroslav Semonský

Monotopic bis-ergolin-2-yl derivatives of alkanes and cycloalkanes (I-VIII) were prepared on reaction of derivatives of ergoline-I (XI-XIV) with ketones in the presence of sulfuric acid or p-toluenesulfonic acid. Esterification of compound XV with cyclohexanol under catalysis with-p-toluenesulfonic acid gave condensation product IX after previous separation of cyclohexyl ester XVI. The condensation products did not exhibit prolactin inhibiting effect.

1984 ◽  
Vol 49 (1) ◽  
pp. 313-319 ◽  
Author(s):  
Věra Přikrylová ◽  
Petr Sedmera ◽  
Josef V. Jizba ◽  
Jindřich Vokoun ◽  
Helena Lipavská ◽  
...  

Reaction of daunomycinone (I) with alcohols and p-toluenesulfonic acid produces a mixture (~3 : 1) of its (7S)- and (7R)-O-alkyl derivatives II-IX. According to the 1H NMR evidence, the alicyclic ring exists in the 9H8 conformation in (7R)-O-alkyl derivatives, on the contrary to (7S)-epimers and 7-epi-daunomycinone that adopt the 8H9 conformation.


1952 ◽  
Vol 30 (3) ◽  
pp. 203-207 ◽  
Author(s):  
Yvon Perron ◽  
Roger Barré

The synthesis of 1,1,1-trichloro-2,2-bis-(p-cyanophenyl)-ethane was carried out with the condensation product of chloral and toluene as starting material. This product was converted, through the corresponding tetraacetate, to 1,1,1-trichloro-2,2-bis-(p-aldehydophenyl)-ethane which in turn reacted with hydroxylamine to give the dioxime. The subsequent dehydration of the latter gave rise to the desired dinitrile. The corresponding dichloro derivatives of the oxime and nitrile were also prepared.


1968 ◽  
Vol 46 (23) ◽  
pp. 3643-3648 ◽  
Author(s):  
Réal Laliberté ◽  
Hilda Warwick ◽  
Georges Médawar

Some derivatives of α-cyano tétrahydro benzothiazoline-Δ2α-acetic acid and their intermediates are described. The lack of reactivity of this class of compounds and products of treatment with concentrated sulfuric acid have been studied. Assignment of configuration was based on infrared and ultraviolet spectroscopic evidence.


1971 ◽  
Vol 49 (17) ◽  
pp. 2797-2802 ◽  
Author(s):  
D. E. Horning ◽  
G. Lacasse ◽  
J. M. Muchowski

The sulfuric acid catalyzed acylation of 2-methyl-5-nitroisocarbostyril with carboxylic acid anhydrides gave the corresponding 4-acylated derivatives 3, which underwent reductive cyclization to 2-substituted derivatives of 4-methyl-1,3,4,5-tetrahydropyrrolo[4.3.2.de]isoquinolin-5-one (4). Alkaline hydrolysis of the six-membered lactam in 4 was accompanied by a retro-Mannich reaction to produce 2-substituted indole-4-carboxylic acids in about 40 % overall yield from 3.


1935 ◽  
Vol 13b (2) ◽  
pp. 61-77 ◽  
Author(s):  
Irene Koerber Buckland ◽  
Fritz Brauns ◽  
Harold Hibbert

The condensation of lignin with phenol by treatment of spruce wood meal with this solvent, using hydrogen chloride as catalyst, yields two chemically different phenol lignins, namely, an ether-insoluble and an ether-dioxane–soluble phenol lignin, in a ratio of approximately 3 to 1. Duplicate preparations gave the same yields of these two fractions, analyses of which gave concordant results, indicating homogeneity and constancy of composition.The analytical results of the ether-insoluble phenol lignin, and of its methylated and acetylated derivatives, can be interpreted on the basis of the Brauns–Hibbert formula for the "native" lignin unit. It is found, in this way, that the ether-insoluble phenol lignin contains three new free phenolic hydroxyl groups capable of methylation with diazomethane, while one phenol group has reacted with one hydroxyl group in the lignin unit with formation of a phenyl-oxygen ether linkage.The analytical results of the ether-dioxane–soluble phenol lignin indicate that a much larger quantity of phenol has condensed with the "native" lignin building unit than in the case of the ether-insoluble fraction. The exact number of phenol molecules reacting to form this condensation product has not been determined experimentally although calculations based on analytical data point to a number as large as 15 or 21.The phenol condensation products were obtained from Freudenberg and Willstätter lignins in nearly quantitative yield and found to differ from the directly extracted phenol lignin in that neither of them could be resolved into two fractions, thus indicating that some change had taken place in the native lignin during the isolation process. The Brauns-Hibbert formula can also be applied to interpret the experimental data in both cases. These lignins appear to contain the same fundamental building unit as the ether-insoluble phenol lignin fraction isolated directly from spruce wood, with the difference that the former probably have one additional hydroxyl group capable of acetylation and diazomethane-methylation.The correlation found to exist in the present investigation between the phenol condensation products from native spruce lignin, isolated Freudenberg lignin and Willstätter lignin is regarded as providing definite experimental evidence indicating the presence of a chemical unit common to various lignins. The phenol condensation products, it is considered, may serve as valuable reference compounds for proving the identity of lignins obtained from different sources and by use of different chemical reagents.


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