Liquid purification or separation – Processes – Liquid/liquid solvent or colloidal extraction or diffusing...
Patent
1990-09-07
1991-11-05
Therkorn, Ernest G.
Liquid purification or separation
Processes
Liquid/liquid solvent or colloidal extraction or diffusing...
210656, 514 26, 536 5, 536 63, 536127, 536128, B01D 1508
Patent
active
050629590
DESCRIPTION:
BRIEF SUMMARY
The subject of the present invention are processes for the working up of mixtures containing cardiac glycosides, such as crude extracts, products of chemical changes and crystallisation steps, as well as mother liquors.
By cardiac glycosides are understood compounds of the general formulae I, II or III acetyl group and D a desoxysugar residue (cf. Ullmann, 3rd ed., Volume 8, pp. 222-231).
For the isolation of cardiac glycosides, such as digoxin, metildigoxin, strophanthrins, lanatosides, from mixtures such as are obtained e.g. in the case of extraction of plant parts, chemical changes and crystallisation operations, laborious processes are generally needed, such as multiple counterflow partition, redissolvings and reprecipitations (cf. for example: Ullmann, loc. cit.).
These processes require the use of large amounts of potentially environment-endangering organic solvents, such as chloroform, dichloromethane, trichloroethylene. The handling of these solvents in large amounts leads to a large technical expense for maintaining the quality of air and water. Additionally the loss of valuable glycosides in non-utilisable mother liquors and concentrates is high.
The invention here is designed to alleviate these problems. The invention, as it is characterised in the claims, solves the task of making available processes for the enrichment and isolation of cardiac glycosides from mixtures, such as crude extracts, products of chemical changes and crystallisation steps, as well as from mother liquors, which manages as far as possible without the potentially environment-endangering solvents required according to the state of the art and, in addition, decreases the losses of valuable glycosides and thus increases product yields.
BRIEF DESCRIPTION OF THE DRAWING
The sole FIGURE shows apparatus suitable for Example 6's recovery of digoxin.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
It has been found that the enrichment and purification of the cardiac glycosides from the mixtures 100 to 1000 m.sup.2 /g and mother liquors described above in detail can be achieved by adsorption on non-polar, large-pored resins from aqueous solutions, possibly with the addition of solvents miscible with water, and subsequent desorption with water-solvent mixtures or pure solvents. It is especially surprising that a separation of the glycoside mixtures into individual compounds or groups is thereby simultaneously possible by variation of the composition of the desorption solution.
The isolation of valuable materials, such as antibiotically-active cephalosporins, from highly diluted solutions with the help of polymeric non-polar resins has been known for a long time. The problem of the enrichment and isolation of cardiac glycosides from complex cardiac glycoside mixtures and especially the dangerous conditions caused by the solvents necessary therefor has been known even longer. Thus, the present invention satisfies a long-existing need.
The adsorption and desorption necessary for the enrichment and isolation according to the invention can be carried out continuously or discontinuously (batch process). Preferably, however, this process is carried out on a column under slight pressure of 1 to 10 bar at temperatures of 20.degree. to 50.degree. C., preferably at room temperature.
For this purpose, one applies to a column filled with a suitable resin the aqueous solution of a crude extract or contaminated glycoside mixture, possibly with the addition of 1-80% of lower alcohols, preferably methanol, ethanol or isopropanol, or of lower ketones, preferably acetone, after the fat-like components have been removed by treatment of the crude extract with a non-polar solvent, preferably hexane, toluene, isohexane or petroleum ether.
All strongly polar materials, such as sugars, are removed from the loaded column by rinsing with water. By the addition of solvents miscible with water, preferably alcohols, lower ketones or cyclic ethers, by addition of salts and adjustment of a particular pH value, the elution solution is so varied that individual cardia
REFERENCES:
patent: 2557916 (1951-09-01), Rosen
patent: 4138474 (1979-02-01), Updike
patent: 4147764 (1979-04-01), Levy
patent: 4151254 (1979-04-01), Gimovsky
patent: 4166104 (1979-08-01), Wagner
patent: 4301139 (1981-11-01), Feingers
patent: 4434236 (1984-02-01), Freytag
patent: 4654311 (1987-03-01), Khanna
patent: 4764601 (1988-08-01), Reuning
Chemical Abstracts, vol. 101, p. 410, Sep. 1984, Abstract 97633y.
Snyder, Introduction to Modern Liquid Chromatography John Wiley & Sons, Inc., New York, 1979, pp. 487-494.
Haring Werner
Lettenbauer Gustav
Machat Rudolf
Ross Carl H.
Boehringer Mannheim GmbH
Therkorn Ernest G.
LandOfFree
Process for the enrichment and/or isolation of heart glycosides does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the enrichment and/or isolation of heart glycosides , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the enrichment and/or isolation of heart glycosides will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-497050