CH427819A - Process for the preparation of heterocyclic compounds - Google Patents
Process for the preparation of heterocyclic compoundsInfo
- Publication number
- CH427819A CH427819A CH345366A CH345366A CH427819A CH 427819 A CH427819 A CH 427819A CH 345366 A CH345366 A CH 345366A CH 345366 A CH345366 A CH 345366A CH 427819 A CH427819 A CH 427819A
- Authority
- CH
- Switzerland
- Prior art keywords
- compound
- denotes
- group
- formula
- thiobarbituric
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 9
- 238000002360 preparation method Methods 0.000 title description 3
- 150000002391 heterocyclic compounds Chemical class 0.000 title description 2
- 239000002253 acid Substances 0.000 claims description 9
- UMGDCJDMYOKAJW-UHFFFAOYSA-N thiourea Chemical compound NC(N)=S UMGDCJDMYOKAJW-UHFFFAOYSA-N 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 7
- 125000000217 alkyl group Chemical group 0.000 claims description 5
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Natural products NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 4
- 150000007513 acids Chemical class 0.000 claims description 4
- -1 alkali metal salt Chemical class 0.000 claims description 4
- 125000002560 nitrile group Chemical group 0.000 claims description 4
- 229920006395 saturated elastomer Polymers 0.000 claims description 4
- 159000000007 calcium salts Chemical class 0.000 claims description 3
- 125000005843 halogen group Chemical group 0.000 claims description 3
- 229910052783 alkali metal Inorganic materials 0.000 claims description 2
- 125000004432 carbon atom Chemical group C* 0.000 claims description 2
- GESHRHVYCSRGQP-UHFFFAOYSA-N diethyl 2-tetradecylpropanedioate Chemical compound CCCCCCCCCCCCCCC(C(=O)OCC)C(=O)OCC GESHRHVYCSRGQP-UHFFFAOYSA-N 0.000 claims description 2
- 239000007859 condensation product Substances 0.000 claims 1
- 125000000753 cycloalkyl group Chemical group 0.000 claims 1
- 125000004177 diethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 claims 1
- 150000002825 nitriles Chemical class 0.000 claims 1
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 6
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 150000003839 salts Chemical class 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
- 239000000243 solution Substances 0.000 description 4
- RVBUGGBMJDPOST-UHFFFAOYSA-N 2-thiobarbituric acid Chemical compound O=C1CC(=O)NC(=S)N1 RVBUGGBMJDPOST-UHFFFAOYSA-N 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 238000009833 condensation Methods 0.000 description 3
- 230000005494 condensation Effects 0.000 description 3
- 239000003960 organic solvent Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 150000001447 alkali salts Chemical class 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 235000010755 mineral Nutrition 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910052708 sodium Inorganic materials 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 125000003903 2-propenyl group Chemical group [H]C([*])([H])C([H])=C([H])[H] 0.000 description 1
- 125000001494 2-propynyl group Chemical group [H]C#CC([H])([H])* 0.000 description 1
- DRSHXJFUUPIBHX-UHFFFAOYSA-N COc1ccc(cc1)N1N=CC2C=NC(Nc3cc(OC)c(OC)c(OCCCN4CCN(C)CC4)c3)=NC12 Chemical compound COc1ccc(cc1)N1N=CC2C=NC(Nc3cc(OC)c(OC)c(OCCCN4CCN(C)CC4)c3)=NC12 DRSHXJFUUPIBHX-UHFFFAOYSA-N 0.000 description 1
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical class [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
- 208000036142 Viral infection Diseases 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- HGCIXCUEYOPUTN-UHFFFAOYSA-N cyclohexene Chemical class C1CCC=CC1 HGCIXCUEYOPUTN-UHFFFAOYSA-N 0.000 description 1
- 125000000113 cyclohexyl group Chemical class [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 125000004051 hexyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 125000000959 isobutyl group Chemical group [H]C([H])([H])C([H])(C([H])([H])[H])C([H])([H])* 0.000 description 1
- 125000001449 isopropyl group Chemical group [H]C([H])([H])C([H])(*)C([H])([H])[H] 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229940057952 methanol Drugs 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 125000001421 myristyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 238000007911 parenteral administration Methods 0.000 description 1
- 125000002958 pentadecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000000825 pharmaceutical preparation Substances 0.000 description 1
- 125000004368 propenyl group Chemical group C(=CC)* 0.000 description 1
- 230000000069 prophylactic effect Effects 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 230000001225 therapeutic effect Effects 0.000 description 1
- 125000002889 tridecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 241000712461 unidentified influenza virus Species 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 230000009385 viral infection Effects 0.000 description 1
Landscapes
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
Description
Verfahren zur Herstellung von,heterocyclischen Verbindungen Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von Thiobarbitursäuren .der Formel
EMI0001.0005
worin R1 einen Alkylrest mit 11-18 Kohlenstoffatomen und R2 einen gesättigten oder ungesättigten, Halogen atome tragenden niederen Alkyl- oder Cycloalkylrest be deutet, sowie deren therapeutisch verträglichen Salzen.
Der Rest R1 in obiger Formel stellt vorzugsweise einen Pentadecyl-, Myristyl-, Tridecyl- oder Laurylrest dar.
Der Rest R2 kann gerade oder verzweigte gesättigte oder ungesättigte niedere Alkylreste darstellen, wie z. B. Methyl, Äthyl, Propyl, Isopropyl, Butyl, Isobutyl, Hexyl; Vinyl, ss-Methylallyl, S,,- Dimethylallyl, Propenyl; Prop- argyl; insbesondere aber Allyl, welche mit einem oder mehreren Halogenatomen substituiert sind.
Als Beispiel eines solchen Restes R2 sei ss-Bromallyl genannt. Bei spiele gesättigter und ungesättigter, halogensubstituierter niederer Cycloalkylreste sind halogensubstituiertes Cyclohexyl, Cyclohexen-(2)-yl etc.
Das erfindungsgemässe Verfahren ist dadurch ge kennzeichnet, dass man eine Verbindung der Formel
EMI0001.0044
worin R3 eine Nitril- oder Carbalkoxygruppe und R4 eine niedere Alkylgruppe darstellen, mit Thioharnstoff kondensiert, und, falls man von einer Verbindung Il ausgegangen ist, in der R, eine Nitrilgruppe bedeutet, die erhaltene 4-Imino-thiobarbiiursäure hydrolysiert.
Die Ausgangsprodukte sind zum Teil bekannte Ver bindungen, welche nach an sich bekannten Methoden hergestellt werden können.
Eine geeignete Ausführungsform der erfindungsge- mässen Kondensation besteht darin, dass man die Aus gangskomponenten in einem geeigneten organischen Lösungsmittel, z. B. einem niederen Alkohol, wie Meth anol oder Äthanol, in Gegenwart eines alkalischen Kondensationsmittels, z. B. Natriumalkoholat, reagieren lässt. Vorteilhafterweise wird bei erhöhter Temperatur gearbeitet, z. B. bei Siedetemperatur des Reaktionsgemi sches. Die Reaktion geht jedoch auch bei niedrigen Temperaturen vor sich. Es ist zweckmässig, die Kon densation bei 50-70 vonstatten gehen zu lassen.
Je nach Temperatur und Substituenten variiert die Reak tionszeit zwischen 1/2-3 Stunden oder mehr. Die gebil dete Thiobarbitursäure wird zweckmässig nach dem Verdünnen mit Wasser oder nach Ahdestillation des Lösungsmittels und Lösen des Rückstandes in Wasser durch Zugabe von Säure, z. B. einer Mineralsäure oder Essigsäure, in Freiheit gesetzt und wird durch Filtration oder Extraktion mit einem organischen Lösungsmittel isoliert.
Falls von einer Verbindung der Formel II ausgegan gen wird, worin R3 eine Nitrilgruppe darstellt, muss, wie gesagt, die nach der Kondensation anfallende 4-Imino- thiobarbitursäure, vorzugsweise durch Behandeln mit Mineralsäure, z. B. Salzsäure, und zwar zweckmässiger- weise mit einer äquivalenten Menge davon, in die ent sprechende Thiobarbitursäure der Formell umgewan delt werden. Die Hydrolyse geschieht z.
B. durch Erhit zen in der äquivalenten Menge verdünnter wässriger Salzsäure unter Rückfluss.
Die erfindungsgemäss erhältlichen neuen Thiobarbi- tursäuren sind aus organischen Lösungsmitteln kristalli- sierbare Verbindungen, welche infolge ihres sauren Charakters in der Lage sind, geeignete Metallsalze, wie Alkalisalze, z. B. Natriumsalze, oder Calciumsalze, zu bilden. Die Alkalisalze werden z.
B. so hergestellt, dass man die Thiobarbitursäure in einem geeigneten Alkohol löst und mit einem Alkalialkoholat oder mit wässrigem Alkali zur Reaktion bringt und. die erhaltenen Salze durch Zugabe eines geeigneten Lösungsmittels zur Ab scheidung bringt. Die Calciumsalze können z. B. aus den Natriumsalzen durch doppelten Umsatz mit Calcium- chlorid gewonnen werden.
Die vorliegenden neuen Thiobarbitursäuren sowie deren therapeutisch verträgliche Alkali- und Erdalkali- salze besitzen wertvolle therapeutische und prophylak tische Wirkungen gegen Virusinfektionen, z.
B. gegen In- fluenzaviren, und können deshalb als Heilmittel in Form pharmazeutischer Präparate, Verwendung finden, wel che sie oder ihre Salze in Mischung mit einem für die enterale oder parenterale Applikation geeigneten phar- mazeutischen, organischen oder anorganischen inerten Trägermaterial enthalten.
Sie können auch noch andere therapeutisch wertvolle Stoffe enthalten.
<I>Beispiel 1</I> Zu einer Lösung von 9,3g Natrium in 90 ml absolu tem Methanol gibt man 13,18 g Thioharnstoff und rührt das Gemisch, bis vollständige Lösung eingetreten ist. Danach gibt man 55 g (ss-Brom-allyl)-myristyl-malon- säurediäthylester (Siedepunkt 190 /0,07 mm) zu.
Das Ganze wird bei einer Badtemperatur von 70 so lange unter Rühren reagieren gelassen, bis sich eine Probe des Ansatzes in Wasser klar löst, was nach etwa zwei Stun den der Fall ist. Danach wird auf Eis gegossen, mit Essigsäure auf einen pH-Wert von 5 eingestellt und mit Äther extrahiert.
Nach dem Abtrennen der ätherischen Schicht wird dieselbe mit Natriumbicarbonatlösung und hernach mit gesättigter Natriumchloridlösung ausge schüttelt, getrocknet und eingeengt. Es bleibt ein dick flüssiges Öl zurück, das in Petroläther (Siedepunkt 60-90 ) in der Wärme gelöst wird. Nach dem Filtrieren und Abkühlen der Lösung kristallisiert 5-(ss-Brom-allyl)- 5-myristyl-2-thiobarbitursäure, welche nach Umkristal lisation aus wässrigem Äthanol bei 90 C schmilzt.
Process for the preparation of heterocyclic compounds The present invention relates to a process for the preparation of thiobarbituric acids of the formula
EMI0001.0005
wherein R1 is an alkyl radical with 11-18 carbon atoms and R2 is a saturated or unsaturated, halogen atom-bearing lower alkyl or cycloalkyl radical, and their therapeutically acceptable salts.
The radical R1 in the above formula preferably represents a pentadecyl, myristyl, tridecyl or lauryl radical.
The radical R2 can represent straight or branched, saturated or unsaturated lower alkyl radicals, such as. B. methyl, ethyl, propyl, isopropyl, butyl, isobutyl, hexyl; Vinyl, ss-methylallyl, S ,, - dimethylallyl, propenyl; Propargyl; but in particular allyl which are substituted by one or more halogen atoms.
An example of such a radical R2 is ß-bromoallyl. Examples of saturated and unsaturated, halogen-substituted lower cycloalkyl radicals are halogen-substituted cyclohexyl, cyclohexen (2) -yl etc.
The inventive method is characterized in that a compound of the formula
EMI0001.0044
where R3 is a nitrile or carbalkoxy group and R4 is a lower alkyl group, condensed with thiourea, and, if a compound II is assumed in which R is a nitrile group, the 4-imino-thiobarbicuric acid obtained is hydrolyzed.
Some of the starting products are known compounds which can be produced by methods known per se.
A suitable embodiment of the condensation according to the invention consists in that one of the starting components in a suitable organic solvent, eg. B. a lower alcohol such as meth anol or ethanol, in the presence of an alkaline condensing agent, e.g. B. sodium alcoholate, can react. It is advantageous to work at an elevated temperature, e.g. B. at the boiling point of the reaction mixture cal. However, the reaction also proceeds at low temperatures. It is advisable to let the condensation take place at 50-70.
Depending on the temperature and substituents, the reaction time varies between 1 / 2-3 hours or more. The gebil ended thiobarbituric acid is expediently after dilution with water or after distilling the solvent and dissolving the residue in water by adding acid, for. B. a mineral acid or acetic acid, and is isolated by filtration or extraction with an organic solvent.
If a compound of the formula II is assumed in which R3 is a nitrile group, the 4-iminothiobarbituric acid obtained after the condensation must, as said, preferably by treatment with mineral acid, e.g. B. hydrochloric acid, and expediently with an equivalent amount thereof, can be converted into the corresponding thiobarbituric acid of the formula. The hydrolysis happens z.
B. by heating zen in the equivalent amount of dilute aqueous hydrochloric acid under reflux.
The novel thiobarbituric acids obtainable according to the invention are compounds which can be crystallized from organic solvents and which, due to their acidic character, are capable of converting suitable metal salts, such as alkali salts, e.g. B. sodium salts, or calcium salts to form. The alkali salts are z.
B. prepared so that the thiobarbituric acid is dissolved in a suitable alcohol and reacts with an alkali metal alcoholate or with an aqueous alkali and. the salts obtained are deposited by adding a suitable solvent. The calcium salts can e.g. B. obtained from the sodium salts by double conversion with calcium chloride.
The present new thiobarbituric acids and their therapeutically acceptable alkali and alkaline earth salts have valuable therapeutic and prophylactic effects against viral infections, eg.
B. against influenza viruses, and can therefore be used as remedies in the form of pharmaceutical preparations which contain them or their salts in a mixture with a pharmaceutical, organic or inorganic inert carrier material suitable for enteral or parenteral administration.
They can also contain other therapeutically valuable substances.
<I> Example 1 </I> 13.18 g of thiourea are added to a solution of 9.3 g of sodium in 90 ml of absolute methanol, and the mixture is stirred until complete dissolution has occurred. Then 55 g of (ss-bromo-allyl) myristyl-malonic acid diethyl ester (boiling point 190 / 0.07 mm) are added.
The whole thing is left to react with stirring at a bath temperature of 70 until a sample of the batch dissolves clearly in water, which is the case after about two hours. It is then poured onto ice, adjusted to pH 5 with acetic acid and extracted with ether.
After separating the ethereal layer, the same is shaken out with sodium bicarbonate solution and then with saturated sodium chloride solution, dried and concentrated. A thick liquid oil remains, which is dissolved in petroleum ether (boiling point 60-90) in the heat. After filtering and cooling the solution, 5- (ss-bromo-allyl) - 5-myristyl-2-thiobarbituric acid crystallizes, which melts after recrystallization from aqueous ethanol at 90 C.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH345366A CH427819A (en) | 1961-09-29 | 1962-07-19 | Process for the preparation of heterocyclic compounds |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH1135661A CH411901A (en) | 1961-09-29 | 1961-09-29 | Process for the preparation of heterocyclic compounds |
| CH345366A CH427819A (en) | 1961-09-29 | 1962-07-19 | Process for the preparation of heterocyclic compounds |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH427819A true CH427819A (en) | 1967-01-15 |
Family
ID=25693039
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH345366A CH427819A (en) | 1961-09-29 | 1962-07-19 | Process for the preparation of heterocyclic compounds |
Country Status (1)
| Country | Link |
|---|---|
| CH (1) | CH427819A (en) |
-
1962
- 1962-07-19 CH CH345366A patent/CH427819A/en unknown
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