CH324082A - Process for the preparation of N-acyl derivatives of 3,5-diamino-2,4,6-triiodo-benzoic acid - Google Patents
Process for the preparation of N-acyl derivatives of 3,5-diamino-2,4,6-triiodo-benzoic acidInfo
- Publication number
- CH324082A CH324082A CH324082DA CH324082A CH 324082 A CH324082 A CH 324082A CH 324082D A CH324082D A CH 324082DA CH 324082 A CH324082 A CH 324082A
- Authority
- CH
- Switzerland
- Prior art keywords
- acid
- triiodo
- diamino
- benzoic acid
- preparation
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 8
- 239000005711 Benzoic acid Substances 0.000 title claims description 3
- 238000002360 preparation method Methods 0.000 title claims description 3
- 239000002253 acid Substances 0.000 claims description 12
- 150000001875 compounds Chemical class 0.000 claims description 7
- 150000008064 anhydrides Chemical class 0.000 claims description 4
- 150000007513 acids Chemical class 0.000 claims description 2
- 125000004122 cyclic group Chemical group 0.000 claims description 2
- 150000004820 halides Chemical class 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 claims 1
- 230000001419 dependent effect Effects 0.000 claims 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- XCZKKZXWDBOGPA-UHFFFAOYSA-N 2-phenylbenzene-1,4-diol Chemical compound OC1=CC=C(O)C(C=2C=CC=CC=2)=C1 XCZKKZXWDBOGPA-UHFFFAOYSA-N 0.000 description 6
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 5
- 239000011630 iodine Substances 0.000 description 5
- 229910052740 iodine Inorganic materials 0.000 description 5
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- 230000010933 acylation Effects 0.000 description 4
- 238000005917 acylation reaction Methods 0.000 description 4
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 239000003610 charcoal Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 230000008030 elimination Effects 0.000 description 3
- 238000003379 elimination reaction Methods 0.000 description 3
- 239000000706 filtrate Substances 0.000 description 3
- 229910052500 inorganic mineral Inorganic materials 0.000 description 3
- 239000011707 mineral Substances 0.000 description 3
- 239000002244 precipitate Substances 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 description 2
- HEDRZPFGACZZDS-UHFFFAOYSA-N Chloroform Chemical compound ClC(Cl)Cl HEDRZPFGACZZDS-UHFFFAOYSA-N 0.000 description 2
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 2
- JUJWROOIHBZHMG-UHFFFAOYSA-N Pyridine Chemical compound C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 2
- WPYMKLBDIGXBTP-UHFFFAOYSA-N benzoic acid Chemical compound OC(=O)C1=CC=CC=C1 WPYMKLBDIGXBTP-UHFFFAOYSA-N 0.000 description 2
- YHASWHZGWUONAO-UHFFFAOYSA-N butanoyl butanoate Chemical compound CCCC(=O)OC(=O)CCC YHASWHZGWUONAO-UHFFFAOYSA-N 0.000 description 2
- -1 dipropionyl compound Chemical class 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 description 1
- OIXRDAZPDINJPT-UHFFFAOYSA-N 2,4,6-triiodo-3,5-bis(propanoylamino)benzoic acid Chemical compound CCC(=O)NC1=C(I)C(NC(=O)CC)=C(I)C(C(O)=O)=C1I OIXRDAZPDINJPT-UHFFFAOYSA-N 0.000 description 1
- CRVYPNHLIAWRNV-UHFFFAOYSA-N 2,4,6-triiodobenzoic acid Chemical compound OC(=O)C1=C(I)C=C(I)C=C1I CRVYPNHLIAWRNV-UHFFFAOYSA-N 0.000 description 1
- MTYCANXGXKRMAI-UHFFFAOYSA-N 3,5-bis(butanoylamino)-2,4,6-triiodobenzoic acid Chemical compound CCCC(=O)NC1=C(I)C(NC(=O)CCC)=C(I)C(C(O)=O)=C1I MTYCANXGXKRMAI-UHFFFAOYSA-N 0.000 description 1
- XCNHOBHCZBIGJP-UHFFFAOYSA-N 3-acetamido-5-amino-2,4,6-triiodobenzoic acid Chemical compound CC(=O)NC1=C(I)C(N)=C(I)C(C(O)=O)=C1I XCNHOBHCZBIGJP-UHFFFAOYSA-N 0.000 description 1
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- WETWJCDKMRHUPV-UHFFFAOYSA-N acetyl chloride Chemical compound CC(Cl)=O WETWJCDKMRHUPV-UHFFFAOYSA-N 0.000 description 1
- 239000012346 acetyl chloride Substances 0.000 description 1
- 150000001447 alkali salts Chemical class 0.000 description 1
- YVPYQUNUQOZFHG-UHFFFAOYSA-N amidotrizoic acid Chemical compound CC(=O)NC1=C(I)C(NC(C)=O)=C(I)C(C(O)=O)=C1I YVPYQUNUQOZFHG-UHFFFAOYSA-N 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N ammonia Natural products N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- 235000010233 benzoic acid Nutrition 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- DAPZDAPTZFJZTO-UHFFFAOYSA-N heptanoyl heptanoate Chemical compound CCCCCCC(=O)OC(=O)CCCCCC DAPZDAPTZFJZTO-UHFFFAOYSA-N 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 150000007530 organic bases Chemical class 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- WYVAMUWZEOHJOQ-UHFFFAOYSA-N propionic anhydride Chemical compound CCC(=O)OC(=O)CC WYVAMUWZEOHJOQ-UHFFFAOYSA-N 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K49/00—Preparations for testing in vivo
- A61K49/04—X-ray contrast preparations
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C233/00—Carboxylic acid amides
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Epidemiology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
Verfahren zur Herstellung von N-Acylderivaten der 3, 5-Diamino-2, 4, 6. trijod. benzoesäure
Die Darstellung der 3, 5-Diamino-2, 4, 6-tri jod-benzoesäure ist bereits besehrieben (vgl.
Berichte der Deutsehen Chem. Ges., Band 29, S. 2835). Diese SÏure ist nach den Angaben der erwähnten Literaturstelle wenig beständig und zersetzt sieh bereits beim Aufbewahren in Substanz oder in Losung unter Bildung schwarzer, schmieriger Produkte, was eine direkte technische oder pharmazeutische Verwendung aussichtslos erscheinen lassen mu¯te.
Es wurde nun gelfunden, dass diese Säure sieh durch Anwendung üblicher Acylierungs methoden trotz ihrer Unstabilität überraschend glatt in ihre N-Acyl-, inshesondere N, N'-Di- acylderivate überführen lässt, die sich als sehr stabile ungefärbte Verbindungen erweisen. biser bisher nicht bekannten Verbindungen besitzen ausser ihrer Stabilität auch sonst noeh eine Reihe technise wertvoller Eigenschaften, wie gute Wasserloslichkeit ihrer Salze und hohen Gehalt an Jod in relativ sehr fester Bindung, die Möglichkeiten einer technischen oder pharmazeutischen Verwendung eröffnen.
Die Acylierung erfolgt beispielsweise durch Umsetzung der zweckmϯig frisch hergestell ten 3. 5-Diamino-2, 4, 6-trijodbenzoesäure mit den Anhydride oder Halogeniden offenkettiger, zyklischer oder gemischt offenkettig- zyklischer mono-odeur Polykarbonsäuren nach den zur Acylierung freier Aminogruppen ge läufigen Methoden. Je nach den angewandten
Acylierungsbedingungen k¯nnen hierbei ne@en den diacylierten auch tetraaeylierte Verbin- dungen oder Anhydride entstehen, die in an sich bekannter Weise jedoch leicht in die Diacylverbindungen der freien Säure überführbar sind.
Beispiel 1
53 g 3, 5-Diamino-2, 4, 6-trijod-benzoesÏure werden mit 400 cm3 Acetanhydrid kurze Zeit ruz Sieden erhitzt und die abgekühlte Losung in einen Liter Wasser eingerührt. Die Acet. ylierungsprodukte scheiden sich alsbald in fester Form ab. Die Fällung wird vervoll- ständigt durch Zusatz von 100 em3 20%iger Salzsäure. Zur Reinigung wird die genannte Fällung in 250 cm3 5%iger Kalilauge bei gewohnlicher Temperatur in Lösung gebracht und naeh Behandlung mit Tierkohle das Filtrat mit Mineralsäure angesäuert.
Nach eini- gen Stunden wird die abgeschiedene 3, 5-Di acetylamino-2, 4, 6-trijodbenzoesÏure isoliert und mit stark verdünnter Salzsäure ausgewaschen. Die auf diese Weise erhaltene farb- lose SÏure ist bereits rein. Sie zersetzt sich beim Erhitzen unter Braunfärbung und Jodabspaltung von 260¯ ab. Die SÏure ist löslieh in Alkohol und Aceton, weniger in Wasser, unlöslieh in Äther, Benzol und Chloroform.
Ihre Alkalisalze und die Salze organischer Basen besitzen eine hohe Loslichkeit in Wasser. Die Ausbeute des Verfahrens beträgt etwa 90 % der Theorie.
Beispiel 2 53 g 3, 5-Diamino-2, 4, 6-trijodbenzoesÏure werden mit 400 em3 Propionsäureanhydrid kurze Zeit zum Sieden erhitzt. Nach dem Ab- kühlen wird in 2 Liter Wassereingerührt. unter weiterem Rühren bis auf 50 erwärmt und 24 Stunden stehengelassen. Die entstan- dene Fällung wird abgesaugt und mit verdünnter Salzsäure und Wasser ausgewaschen.
Die erhaltene Tetrapropionylverbindung vom F. = 129 wird zur Reinigung und ¯berf hrung in die Dipropionylverbindung in der eben ausreichenden Menge verdünnter Kalilauge unter Zusatz von Tierkohle gelost, filtriert und das Filtrat mit Mineralsäure gefällt.
Die auf diese Weise erhaltene 3, 5-Dipropionylamino-2, 4, 6-trijodbenzoesÏure ist rein. Sie zersetzt sich beim Erhitzen nach vorhergehender Jodabspaltung bei 238 . Die Ausbeute betrÏgt 50 g = etwa 78"/o der Theorie.
Beispiel 3 53 g 3, 5-Diamino-2, 4, 6-trijod-benzoesÏure werden mit 275 em3 n-Buttersäureanhydrid mit einigen Tropfen konzentrierter Schwefel- sÏure unter Rühren erst eine Stunde auf 130 , dann 30 Minuten auf 150 erhitzt. Buttersäure und Buttersäureanhydrid wird im Vakuum abdestilliert, der Rüekstand mit wässrigem Ammoniak bei etwa 60 in Losung gebracht und mit Kohle filtriert. Ansäuern des Filtrats mit MineralsÏure liefert die reine 3, 5-Di- butyrylamino-2, 4, 6-trijod-benzoesäure als flok kigen, farblosen Niedersehlag mit 75%iger Ausbeute. Die Substanz zersetzt sieh beim Erhitzen bei 267¯ unter Jodabspaltung.
Beispiel 4
53 g 3, 5-Diamino-2, 4, 6-trijod-benzoesäure und 300 em3 Önanthsäureanhydrid werden naeh Zusatz einiger Tropfen konzentrierter Sehwefelsäure unter Rühren auf 135 erhitzt und bei dieser Temperatur 30 Minuten gehalten. Naeh Abkühlung wurde die abgeschiedene Substanz abgesaugt und mit Ather ausgewaschen. Die erhaltene 3, 5-Di¯nanthoylamino 2, 4, 6-trijod-benzoesÏure ist rein. Beim Er- hitzen verfärbt sie sieh von 245 an, um sieh bei 258 unter Jodabspaltung zu zersetzen.
Die Ausbeute beträgt 80% der Theorie.
Beispiel 5 3-Acetylamino-5-amino-2, 4, 6-trijod benzoesÏure
10, 6 g 3, 5-Diamino-2,4,6-trijod-benzoesÏure (2/100 Mol) werden in 25 cm3 Dioxan warm gelöst, unter Abkühlung der Losung auf 10 bis 15 4/100 Mol Pyridin und 4/100 Mol Acetylehlorid hinzugefügt und einige Stunden bei dieser Temperatur gehalten. Die Fällung wird isoliert und mit Wasser ausgewaschen.
Die vorliegende 3-Aeetylamino-5-amino-2, 4, 6trijod-benzoesäure schmilzt bei 162 .
Process for the preparation of N-acyl derivatives of 3, 5-diamino-2, 4, 6th triiodine. benzoic acid
The representation of the 3, 5-diamino-2, 4, 6-triiodo-benzoic acid has already been described (cf.
Reports from Deutsehen Chem. Ges., Volume 29, p. 2835). According to the information in the cited literature, this acid is not very stable and decomposes even when stored in substance or in solution to form black, greasy products, which should make direct technical or pharmaceutical use seem futile.
It has now been found that this acid can be converted surprisingly smoothly into its N-acyl, in particular N, N'-diacyl derivatives, which are very stable uncolored compounds, by using conventional acylation methods, despite its instability. In addition to their stability, the previously unknown compounds also have a number of technically valuable properties, such as good water solubility of their salts and high iodine content in a relatively very strong bond, which open up possibilities for technical or pharmaceutical use.
The acylation is carried out, for example, by reacting the expediently freshly prepared 3. 5-diamino-2, 4, 6-triiodobenzoic acid with the anhydrides or halides of open-chain, cyclic or mixed open-chain-cyclic mono-odeur polycarboxylic acids after the amino groups free for acylation common methods. Depending on the applied
Acylation conditions can result from the diacylated as well as tetraaeylated compounds or anhydrides, which, however, can easily be converted into the diacyl compounds of the free acid in a manner known per se.
example 1
53 g of 3, 5-diamino-2, 4, 6-triiodo-benzoic acid are briefly heated to the boil with 400 cm3 of acetic anhydride and the cooled solution is stirred into one liter of water. The acet. ylation products are soon deposited in solid form. The precipitation is completed by adding 100 cubic meters of 20% hydrochloric acid. For purification, the above-mentioned precipitation is dissolved in 250 cm3 of 5% potassium hydroxide solution at normal temperature and, after treatment with animal charcoal, the filtrate is acidified with mineral acid.
After a few hours, the 3, 5-diacetylamino-2, 4, 6-triiodobenzoic acid which has separated out is isolated and washed out with very dilute hydrochloric acid. The colorless acid obtained in this way is already pure. It decomposes when heated, turning brown and splitting off iodine of 260¯. The acid is soluble in alcohol and acetone, less in water, and insoluble in ether, benzene and chloroform.
Their alkali salts and the salts of organic bases have a high solubility in water. The yield of the process is about 90% of theory.
Example 2 53 g of 3,5-diamino-2, 4, 6-triiodobenzoic acid are heated to the boil for a short time with 400 cubic meters of propionic anhydride. After cooling, it is stirred into 2 liters of water. heated to 50 with further stirring and left to stand for 24 hours. The resulting precipitate is filtered off with suction and washed out with dilute hydrochloric acid and water.
The obtained tetrapropionyl compound of F. = 129 is for purification and conversion into the dipropionyl compound in the just sufficient amount of dilute potassium hydroxide solution with the addition of animal charcoal, filtered and the filtrate is precipitated with mineral acid.
The 3, 5-dipropionylamino-2, 4, 6-triiodobenzoic acid obtained in this way is pure. It decomposes on heating after previous iodine elimination at 238. The yield is 50 g = about 78 "/ o of theory.
EXAMPLE 3 53 g of 3,5-diamino-2, 4, 6-triiodo-benzoic acid are heated with 275 cubic meters of n-butyric anhydride with a few drops of concentrated sulfuric acid with stirring, first to 130 for one hour and then to 150 for 30 minutes. Butyric acid and butyric anhydride are distilled off in vacuo, the residue is dissolved with aqueous ammonia at about 60 ° and filtered with charcoal. Acidification of the filtrate with mineral acid gives the pure 3, 5-di-butyrylamino-2, 4, 6-triiodo-benzoic acid as a flaky, colorless precipitate with 75% yield. The substance decomposes when heated at 267¯ with elimination of iodine.
Example 4
53 g of 3, 5-diamino-2, 4, 6-triiodo-benzoic acid and 300 em3 of enanthic anhydride are heated to 135 with stirring after adding a few drops of concentrated sulfuric acid and kept at this temperature for 30 minutes. After cooling, the deposited substance was suctioned off and washed out with ether. The 3, 5-Dīnanthoylamino 2, 4, 6-triiodo-benzoic acid obtained is pure. On heating it changes color from 245 to 258 to decompose with elimination of iodine.
The yield is 80% of theory.
Example 5 3-Acetylamino-5-amino-2, 4, 6-triiodobenzoic acid
10.6 g of 3,5-diamino-2,4,6-triiodo-benzoic acid (2/100 mol) are dissolved warm in 25 cm3 of dioxane, while cooling the solution to 10 to 15 4/100 mol of pyridine and 4/100 Mol acetyl chloride added and kept at this temperature for a few hours. The precipitate is isolated and washed out with water.
The present 3-ethylamino-5-amino-2, 4, 6-triiodo-benzoic acid melts at 162.
Claims (1)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE324082X | 1953-02-05 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH324082A true CH324082A (en) | 1957-08-31 |
Family
ID=6177326
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH324082D CH324082A (en) | 1953-02-05 | 1954-02-01 | Process for the preparation of N-acyl derivatives of 3,5-diamino-2,4,6-triiodo-benzoic acid |
Country Status (1)
| Country | Link |
|---|---|
| CH (1) | CH324082A (en) |
-
1954
- 1954-02-01 CH CH324082D patent/CH324082A/en unknown
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