Preliminary Note on Dietthio and Diethylsulphone derivatives of Succinic Acid

1897 ◽  
Vol 21 ◽  
pp. 156-159
Author(s):  
Crum Brown ◽  
R. Fairbairn

Sodium mercaptide and dibromosuccinic ether, in the proportion of two molecules of the former to one of the latter, were dissolved separately in absolute alcohol, and slowly mixed. A considerable evolution of heat took place, while sodium bromide separated out. The flask was then digested for some hours on the steam-bath. The alcohol was subsequently distilled off, and the residue, on cooling, was treated with water. An oil separated out. This oil was collected by means of a separating funnel, and the aqueous layer several times extracted with ether. The oil and the ethereal extracts were added together and dried over calcium chloride. Next morning the ether was distilled off at the ordinary pressure. The remainder was distilled in vacuo. Between 50° and 60° a few drops came over, which proved to be ethyldisulphide.The remainder came over between 150° and 170°.This latter fraction was redistilled, and a portion of it used for analysis. The boiling point at 20 mm. pressure was 160°.Combustion of dietthiosuccinic ether.Weight of substance taken = ·2477 gram.Weight of carbonic acid obtained = ·4476 gram.Weight of water obtained = ·1702 gram.

1999 ◽  
Vol 54 (9) ◽  
pp. 1133-1137
Author(s):  
Astrid Knieß ◽  
Margit Gruner ◽  
Roland Mayer

ß-Oxo-1 and 9-anthracenepropionate (6 and 7) reacts with DMF-acetale to enaminones 10 and 11. The reaction of 2-(dimethylamino)methylen-substituted ß-oxo-1 -anthracenepropionate (10) with hydrazines yields 5-(l-anthracenyl)-pyrazol-4-carboxylates (13). In contrast, the cyclocondensation of 3-(9-anthracenyl)-2-(dimethylamino)methylen-3-oxo-propionate (11) with hydrazine hydrochlorides gives 4-(9-anthracenoyl)-5-hydroxy-pyrazoles (14). This is caused by the sterical hindrance of the carbonyl group of the anthracene derivatives in position 9; thus, the cyclocondensation proceeds via reaction of the ester group of the enaminone 11.


Biomolecules ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 175 ◽  
Author(s):  
Ying He ◽  
Yuan Jia ◽  
Fachuang Lu

Various ferulic acid (FA) dimers occurring in plant cell walls, such as 8-5-, 8-O-4-, 5-5-, and 8-8-coupled dimers, are effective antioxidants and potential antimicrobials. It is necessary to access these diferulates as reference compounds to validate those isolated from plants. 3,6-bis(4-hydroxy-3-methoxyphenyl)-tetrahydrofuro-[3,4-c]furan-1,4-dione, a 8-8-coupled FA dilactone generated from ferulic acid via radical coupling, has been used to synthesize 8-8-coupled FA dimers although few reports investigated the distribution of products and mechanisms involved in the transformation of FA dilactone. In this work, the FA dilactone, obtained from FA by a peroxidase-catalyzed radical coupling, was reacted under various base/acid conditions. Effects of reaction conditions and workup procedures on the distribution of products were investigated by GC-MS. The isolated products from such treatments of FA dilactone were characterized by NMR. New derivatives of FA dimer including 2-(4-hydroxy-3-methoxybenzylidene)-3-(hydroxyl-(4-hydroxy-3-methoxyphenyl)methyl)succinic acid and 2-(bis(4-hydroxy-3-methoxyphenyl)-methyl)-succinic acid were produced from NaOH treatment. Another novel 8-8-coupled cyclic FA dimer, diethyl 6-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-methoxy-1,2-dihydronaphthalene-2,3-dicarboxylate was identified in products from FA dilactone treated by dry HCl in absolute ethanol. Mechanisms involved in such transformations were proposed.


1977 ◽  
Author(s):  
R. von Hugo ◽  
R. Hafter ◽  
A. Stemberger ◽  
H. Graeff

Crosslinked high molecular weight derivatives of fibrin (fibrinoligomers) were observed during intravascular coagulation. It was the purpose of this study to investigate the complex formation of fibrin oligomers with fibrinogen and fibrinmonomer. Fibrinogen coupled to agarose (Fg-ag) as well as fi-brinmonomer coupled to agarose (Fm-ag) was used as substrate. Soluble oligomers of fibrin were produced by incubating fibrinogen with thrombin, calcium-chloride, cystein and F XIII. They were separated from fibrinogen by gel filtration. Γ-dimers were demonstrated in fractions from the void volume and the shoulder prior to the fibrinogen peak. These fractions were subjected to affinity chromatography. Crosslinked oligomers of fibrin were not adsorbed on Fg-ag, yet adsorption occured on Fm-ag. This indicates that fibrin oligomers have no affinity to fibrinogen, yet readily form complexes with fibrin. This could mean that in vivo they compete with fibrinogen for the fibrinmonomer part of soluble fibrin monomer complexes, and hence have a tendency to increase in size.


1977 ◽  
Vol 8 (28) ◽  
pp. no-no
Author(s):  
J. LANGE ◽  
S. RUMP ◽  
E. GALECKA ◽  
L. ILCZUK ◽  
M. LECHOWSKA-POSTEK ◽  
...  

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