CA1212943A - Method for the preparation of 1,8-dihydroxy-10-acyl-9- anthrones, especially for use in the treatment of psoriasis - Google Patents
Method for the preparation of 1,8-dihydroxy-10-acyl-9- anthrones, especially for use in the treatment of psoriasisInfo
- Publication number
- CA1212943A CA1212943A CA000454593A CA454593A CA1212943A CA 1212943 A CA1212943 A CA 1212943A CA 000454593 A CA000454593 A CA 000454593A CA 454593 A CA454593 A CA 454593A CA 1212943 A CA1212943 A CA 1212943A
- Authority
- CA
- Canada
- Prior art keywords
- dihydroxy
- anthrone
- acyl
- formula
- preparation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
- C07C49/703—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups
- C07C49/723—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups polycyclic
- C07C49/727—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups polycyclic a keto group being part of a condensed ring system
- C07C49/737—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups polycyclic a keto group being part of a condensed ring system having three rings
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C49/00—Ketones; Ketenes; Dimeric ketenes; Ketonic chelates
- C07C49/587—Unsaturated compounds containing a keto groups being part of a ring
- C07C49/703—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups
- C07C49/747—Unsaturated compounds containing a keto groups being part of a ring containing hydroxy groups containing six-membered aromatic rings
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- A61P17/00—Drugs for dermatological disorders
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Pharmacology & Pharmacy (AREA)
- Animal Behavior & Ethology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Dermatology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Pyridine Compounds (AREA)
- Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Cosmetics (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE:
The invention relates to a method for the preparation of 1,8-dihydroxy-10-acyl-9-anthrone, especially for use in the treatment of psoriasis, having the formula
The invention relates to a method for the preparation of 1,8-dihydroxy-10-acyl-9-anthrone, especially for use in the treatment of psoriasis, having the formula
Description
The present invention relates to a methGd for the preparation of 1,8-dihydroxy-10-acyl-9-anthrones, especially for use in the treatment of psoriasis.
1,8-Dih~droxy-9-anthrones substituted in the 10-S position have been used for a Eew years to replace dithranol, which has been known since 1916 and used for the treatment of psoriasis, and which strongly stains the skin and clothing in addition to strongly inflaming the skin.
The structural formula of 1,8-dihydroxy-10-acyl-9-anthrones is as follows:
HO O OH
1~ ~
CO-R
where R is an alkyl group having from 2 to 4 carbon atoms.
Finnish Patent FI 57743 discloses a method for preparing these compounds, which method consists in causing anthraline to react in boiling benzene with an acid chloride in the presence of pyridine. In this method, the acid chloride is used in an excess of 20%. The reaction mixture is boiled using return condensation for 10 hours, and the product is crystallized out from acetic acid. The yield in the method in question is, for example, only 25.5% of the theoretical.
The object of the present invention is to provide an improved method for the preparation of these compounds, which method has considerable advantages. By way of example, this new method can be carried out at a reaction temperature which is as low as -10C. In any case, it makes it possible to use very low reaction temperatures, for example room temperature. In addition, this new method makes it possible to avoid using benzene, which is ,~ - 1 -~2~ 3 strongly carcinogenic, and to use, for example, toluene, which is less harmful. Furthermore, the yield can be incxeased to 2- to 3-fold as compared with the method of Finnish Patent FI 57743.
The present invention provides a method for the preparation of l,8-dihydroxy-10-acyl-9-anthrone, especially for use in the treatment of psoriasis, having the formula lo ~$
co ~
where R is an alkyl group having 2 to 4 carbon atoms, wherein 1,8-dihydroxy-9-anthrone having the formula HO O OH
~ O
is reacted with an acid chloride having the formula RCCl, where R is as defined above, in the presence of a solvent characterized in that the reaction is carried out in the presence of 2,6-dimethyl pyridine.
The invention is based on the observation that the replacement of pyridine with 2,6-dimethyl pyridine makes it possible to lower the reaction temperature, to use toluene, xylene or chlorinated hydrocarbons such as dichloromethane or tetrachloroethene instead o~ benzene, and even to triple the yield as compared with the known method. If, urther-more, the acid chloride is used in an excess of 100 ~, thereaction can be completed in two hours.
From the above-mentioned low reaction temperature, which can be for example ~10C to +20C, it follows that the amount of impurities passing into the completed 1~8-dihydroxy-
1,8-Dih~droxy-9-anthrones substituted in the 10-S position have been used for a Eew years to replace dithranol, which has been known since 1916 and used for the treatment of psoriasis, and which strongly stains the skin and clothing in addition to strongly inflaming the skin.
The structural formula of 1,8-dihydroxy-10-acyl-9-anthrones is as follows:
HO O OH
1~ ~
CO-R
where R is an alkyl group having from 2 to 4 carbon atoms.
Finnish Patent FI 57743 discloses a method for preparing these compounds, which method consists in causing anthraline to react in boiling benzene with an acid chloride in the presence of pyridine. In this method, the acid chloride is used in an excess of 20%. The reaction mixture is boiled using return condensation for 10 hours, and the product is crystallized out from acetic acid. The yield in the method in question is, for example, only 25.5% of the theoretical.
The object of the present invention is to provide an improved method for the preparation of these compounds, which method has considerable advantages. By way of example, this new method can be carried out at a reaction temperature which is as low as -10C. In any case, it makes it possible to use very low reaction temperatures, for example room temperature. In addition, this new method makes it possible to avoid using benzene, which is ,~ - 1 -~2~ 3 strongly carcinogenic, and to use, for example, toluene, which is less harmful. Furthermore, the yield can be incxeased to 2- to 3-fold as compared with the method of Finnish Patent FI 57743.
The present invention provides a method for the preparation of l,8-dihydroxy-10-acyl-9-anthrone, especially for use in the treatment of psoriasis, having the formula lo ~$
co ~
where R is an alkyl group having 2 to 4 carbon atoms, wherein 1,8-dihydroxy-9-anthrone having the formula HO O OH
~ O
is reacted with an acid chloride having the formula RCCl, where R is as defined above, in the presence of a solvent characterized in that the reaction is carried out in the presence of 2,6-dimethyl pyridine.
The invention is based on the observation that the replacement of pyridine with 2,6-dimethyl pyridine makes it possible to lower the reaction temperature, to use toluene, xylene or chlorinated hydrocarbons such as dichloromethane or tetrachloroethene instead o~ benzene, and even to triple the yield as compared with the known method. If, urther-more, the acid chloride is used in an excess of 100 ~, thereaction can be completed in two hours.
From the above-mentioned low reaction temperature, which can be for example ~10C to +20C, it follows that the amount of impurities passing into the completed 1~8-dihydroxy-
- 2 -1~ 29~3 10-acyl-9-anthrone is small. Thus the purification is a simple procedure compared with the respective procedure in the known method. Acetonitrile or 2-propanol are suitable for use as the recrystallization solvent along with or instead of acetic acid.
The compounds prepared in accordance with the invention can be used in, for example, vaseline- or paraffin-based skin creams in concentrations of 0.5 - 5 %, in sticks intended for skin care in concentrations of, for example, 2 - 8 %, and in gels and in film-forming solutions.
The following examples illustrate the invention in greater detail.
Examp~ 1 Butyryl chloride in an amount of 207 ml (213 g, 2.0 mol) was added in the course of 2 hours at a temperature below 0C to a mixture which contained 2500 ml toluene, 226 g (1.0 mol) 1,8-dihydroxy-9-anthrone and 232 ml (214 g, 2.0 mol3 2,6-dimethyl pyridine.
The mixture was stirred at a temperature below 0C
for a further two hours after the addition.
The mixture was thereafter heated to +40C, the hydrochloride of the 2j6-dimethyl pyridine was filtered off, and most of the toluene was evaporated at lowered pressure.
2300 ml isopropanol was added to the residue, the mixture was cooled to -10C, and the precipitate was recovered by filtration. Recrystallization was carried out from aceto-nitrile, whereby a yield of 222 g 1,8-dihydroxy-10-butyryl-9-anthrone was obtained. This was 75 % of the theoretical.
Example 2 39 The procedure was fully analogous to that in Example 1, except that xylene was used instead of toluene.
The yield was the same as in Example 17 i.e. 75 %.
Example 3 Propionyl chloride in an amount of 86.9 ml (92.5 g, :~2~L~943 1 mol) was added in the course of about 2 hours at a temperature below 0C to a mixture which contained 1200 ml toluene, 113 g ~0.5 mol) 1,8-dihydroxy-9-anthrone and 116 ml (107 g, 1 mol) 2,6-dimethyl pyridine. Stirring was continued for a further two hours after the addition.
The 1,8-dihydroxy 10-propionyl-9-anthrone obtained as the result was separated by the procedure presented in Example 1. The yield was (120 g3 82 % of the theoretical.
Exa~ple 4 Starting from 1~8-dihydroxy-9-anthrone and valeryl chloride and using valeryl chloride in an excess of 100 %
and by proceeding otherwise as in Example 1, 1,8-dihydroxy-10-valeryl-9-anthrone was obtained as the result, the yield being 53 %.
Example 5 Pharmaceutical compositions were prepared by using the following constituents and amounts:
liquid paraffin 40 - 60 ~
solid paraffin 40 - 60 %
microcrystalline wax 0~5 - 5 %
In addition, about 2 - 8 % 1,8-dihydroxy-10-butyryl-9-anthrone was mixed with the carrier composition presented above. Sticks intended for skin care were molded ~rom the mixture, and it was observed that the use properties of the sticks were good and, furthermore, the medication in the sticks remained unchanged, specifically unoxidized.
The compounds prepared in accordance with the invention can be used in, for example, vaseline- or paraffin-based skin creams in concentrations of 0.5 - 5 %, in sticks intended for skin care in concentrations of, for example, 2 - 8 %, and in gels and in film-forming solutions.
The following examples illustrate the invention in greater detail.
Examp~ 1 Butyryl chloride in an amount of 207 ml (213 g, 2.0 mol) was added in the course of 2 hours at a temperature below 0C to a mixture which contained 2500 ml toluene, 226 g (1.0 mol) 1,8-dihydroxy-9-anthrone and 232 ml (214 g, 2.0 mol3 2,6-dimethyl pyridine.
The mixture was stirred at a temperature below 0C
for a further two hours after the addition.
The mixture was thereafter heated to +40C, the hydrochloride of the 2j6-dimethyl pyridine was filtered off, and most of the toluene was evaporated at lowered pressure.
2300 ml isopropanol was added to the residue, the mixture was cooled to -10C, and the precipitate was recovered by filtration. Recrystallization was carried out from aceto-nitrile, whereby a yield of 222 g 1,8-dihydroxy-10-butyryl-9-anthrone was obtained. This was 75 % of the theoretical.
Example 2 39 The procedure was fully analogous to that in Example 1, except that xylene was used instead of toluene.
The yield was the same as in Example 17 i.e. 75 %.
Example 3 Propionyl chloride in an amount of 86.9 ml (92.5 g, :~2~L~943 1 mol) was added in the course of about 2 hours at a temperature below 0C to a mixture which contained 1200 ml toluene, 113 g ~0.5 mol) 1,8-dihydroxy-9-anthrone and 116 ml (107 g, 1 mol) 2,6-dimethyl pyridine. Stirring was continued for a further two hours after the addition.
The 1,8-dihydroxy 10-propionyl-9-anthrone obtained as the result was separated by the procedure presented in Example 1. The yield was (120 g3 82 % of the theoretical.
Exa~ple 4 Starting from 1~8-dihydroxy-9-anthrone and valeryl chloride and using valeryl chloride in an excess of 100 %
and by proceeding otherwise as in Example 1, 1,8-dihydroxy-10-valeryl-9-anthrone was obtained as the result, the yield being 53 %.
Example 5 Pharmaceutical compositions were prepared by using the following constituents and amounts:
liquid paraffin 40 - 60 ~
solid paraffin 40 - 60 %
microcrystalline wax 0~5 - 5 %
In addition, about 2 - 8 % 1,8-dihydroxy-10-butyryl-9-anthrone was mixed with the carrier composition presented above. Sticks intended for skin care were molded ~rom the mixture, and it was observed that the use properties of the sticks were good and, furthermore, the medication in the sticks remained unchanged, specifically unoxidized.
Claims (5)
1. A method for the preparation of 1,8-dihydroxy-10-acyl-9-anthrone having the formula where R is an alkyl group having 2 to 4 carbon atoms, wherein 1,8-dihydroxy-9-anthrone having the formula is reacted with an acid chloride having the formula where R is as defined above, in the presence of a solvent characterized in that the reaction is carried out in the presence of 2,6-dimethyl pyridine.
2. A method according to claim 1, characterized in that the solvent is selected from the group consisting of toluene, xylene and chlorinated hydrocarbons.
3. A method according to claim 2, wherein the chlorinated hydrocarbons are selected from the group consist-ing of dichloromethane and tetrachloroethane.
4. A method according to claim 1, characterized in that the acid chloride is used in an excess of 100 %.
5. A method according to claim 1, characterized in that the reaction temperature is -10 to +20°C, the acid chloride is added in the course of two hours, and the stirring is continued for a further two hours.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI831739A FI66585C (en) | 1983-05-18 | 1983-05-18 | FOERFARANDE FOER FRAMSTAELLNING AV SAERSKILT VID BEHANDLING AVSORIASIS ANVAENDBARA 1,8-DIHYDROXI-10-ACYL-9-ANTRONER |
| FI831739 | 1983-05-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1212943A true CA1212943A (en) | 1986-10-21 |
Family
ID=8517222
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000454593A Expired CA1212943A (en) | 1983-05-18 | 1984-05-17 | Method for the preparation of 1,8-dihydroxy-10-acyl-9- anthrones, especially for use in the treatment of psoriasis |
Country Status (31)
| Country | Link |
|---|---|
| JP (1) | JPS59212443A (en) |
| KR (1) | KR840009059A (en) |
| AU (1) | AU560079B2 (en) |
| BE (1) | BE899334A (en) |
| CA (1) | CA1212943A (en) |
| CH (1) | CH659464A5 (en) |
| CS (1) | CS256379B2 (en) |
| DD (1) | DD223702A5 (en) |
| DE (1) | DE3418382A1 (en) |
| DK (1) | DK154207C (en) |
| ES (1) | ES8505167A1 (en) |
| FI (1) | FI66585C (en) |
| FR (1) | FR2546162B1 (en) |
| GB (1) | GB2140007B (en) |
| GR (1) | GR79971B (en) |
| HU (1) | HUT36076A (en) |
| IL (1) | IL71446A (en) |
| IN (1) | IN156115B (en) |
| IS (1) | IS2902A7 (en) |
| IT (1) | IT1173473B (en) |
| LU (1) | LU85292A1 (en) |
| NL (1) | NL8401074A (en) |
| NO (1) | NO157099C (en) |
| NZ (1) | NZ207592A (en) |
| PH (1) | PH20038A (en) |
| PL (1) | PL141866B1 (en) |
| PT (1) | PT78603B (en) |
| SE (1) | SE453827B (en) |
| SU (1) | SU1240351A3 (en) |
| YU (1) | YU81784A (en) |
| ZA (1) | ZA842223B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2492372A1 (en) * | 1980-10-21 | 1982-04-23 | Cird | 1,8-DIHYDROXY-9-ANTHRONES SUBSTITUTED IN POSITION 10 AND THEIR USE IN HUMAN OR VETERINARY MEDICINE AND IN COSMETICS |
| FR2591222B1 (en) * | 1985-12-11 | 1988-07-22 | Cird | MONO, DI AND TRI-ESTERS OF 1,8-DIHYDROXY PHENYL-10 ANTHRONE-9 OR ANTHRANOL-9, THEIR PREPARATION PROCESS AND THEIR USE IN HUMAN OR VETERINARY MEDICINE AND IN COSMETICS |
| US4843097A (en) * | 1984-06-13 | 1989-06-27 | Groupement D'interet Economique Dit: Centre International De Recherches Dermatologiques C.I.R.D. | 10-aryl-1,8-dihydroxy-9-anthrones and their esters, process for preparing same, and use of same in human and veterinary medicine and in cosmetics |
| FR2566772B1 (en) * | 1984-06-29 | 1986-11-14 | Cird | DIACYLOXY-1,8 ACYL-10 ANTHRONES, THEIR PREPARATION PROCESS AND THEIR USE IN HUMAN OR VETERINARY MEDICINE AND IN COSMETICS |
| FR2580631B1 (en) * | 1985-04-17 | 1987-05-29 | Cird | HYDROXY-1 ACYLOXY-8 ACYL-10 ANTHRONES, THEIR PREPARATION PROCESS AND THEIR USE IN HUMAN OR VETERINARY MEDICINE AND IN COSMETICS |
| DE69223723T2 (en) * | 1991-10-04 | 1998-04-16 | Fisher & Paykel | humidifier |
| DE4231636A1 (en) * | 1992-09-22 | 1994-03-24 | Beiersdorf Ag | New anthrone and anthracene derivatives substituted in the 10-position, processes for their preparation, pharmaceutical or cosmetic compositions containing these compounds and their use |
| US5426197A (en) * | 1993-07-19 | 1995-06-20 | Teva Pharmaceutical Industries, Ltd. | 10-substituted 1,8-dihydroxy-9(10H) anthracenone pharmaceuticals |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI57743C (en) * | 1979-03-29 | 1980-10-10 | Orion Yhtymae Oy | FREQUENCY REQUIREMENT FOR NYA 1,8-DIHYDROXI-10-ACYL-9-ANTRONER MOT PSORIASIS |
-
1983
- 1983-05-18 FI FI831739A patent/FI66585C/en not_active IP Right Cessation
-
1984
- 1984-03-22 NZ NZ207592A patent/NZ207592A/en unknown
- 1984-03-22 AU AU25998/84A patent/AU560079B2/en not_active Ceased
- 1984-03-23 IT IT20213/84A patent/IT1173473B/en active
- 1984-03-26 ZA ZA842223A patent/ZA842223B/en unknown
- 1984-03-29 IN IN209/CAL/84A patent/IN156115B/en unknown
- 1984-03-30 DK DK173584A patent/DK154207C/en active IP Right Grant
- 1984-04-04 GB GB08408666A patent/GB2140007B/en not_active Expired
- 1984-04-04 NL NL8401074A patent/NL8401074A/en not_active Application Discontinuation
- 1984-04-05 IL IL71446A patent/IL71446A/en not_active IP Right Cessation
- 1984-04-05 GR GR74318A patent/GR79971B/el unknown
- 1984-04-05 BE BE0/212698A patent/BE899334A/en not_active IP Right Cessation
- 1984-04-05 IS IS2902A patent/IS2902A7/en unknown
- 1984-04-06 LU LU85292A patent/LU85292A1/en unknown
- 1984-04-18 CS CS842911A patent/CS256379B2/en unknown
- 1984-04-18 ES ES531760A patent/ES8505167A1/en not_active Expired
- 1984-04-27 KR KR1019840002278A patent/KR840009059A/en not_active Application Discontinuation
- 1984-05-02 FR FR8406790A patent/FR2546162B1/en not_active Expired
- 1984-05-04 JP JP59090047A patent/JPS59212443A/en active Pending
- 1984-05-08 SU SU843735603A patent/SU1240351A3/en active
- 1984-05-10 YU YU00817/84A patent/YU81784A/en unknown
- 1984-05-16 PH PH30686A patent/PH20038A/en unknown
- 1984-05-16 NO NO841965A patent/NO157099C/en unknown
- 1984-05-16 SE SE8402649A patent/SE453827B/en not_active IP Right Cessation
- 1984-05-17 DE DE19843418382 patent/DE3418382A1/en not_active Withdrawn
- 1984-05-17 PT PT78603A patent/PT78603B/en unknown
- 1984-05-17 CH CH2431/84A patent/CH659464A5/en not_active IP Right Cessation
- 1984-05-17 HU HU841908A patent/HUT36076A/en unknown
- 1984-05-17 CA CA000454593A patent/CA1212943A/en not_active Expired
- 1984-05-17 DD DD84263131A patent/DD223702A5/en unknown
- 1984-05-17 PL PL1984247724A patent/PL141866B1/en unknown
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| MKEX | Expiry |