JPS59155400A - Improved preparation of c-amp acyl derivative - Google Patents

Abstract

PURPOSE:To obtain an N<6>,2'-O-diacyladenosine-3',5'-cyclic phosphate useful as a drug and a reagent advantageously, by reacting adenosine-3',5'-cyclic phosphoric acid with a carboxylic acid anhydride in the presence of a tertiary amine under heating, treating the resultant product with a salt exchanging agent. CONSTITUTION:Adenosine-3',5'-cyclic phosphoric acid is reacted with preferably 3-6 times the molar quantity of carboxylic acid anhydride(e.g., acetic anhydride, etc.) in the presence of preferably 1-3 times the molar quantity of a tertiary amine under heating to form N<6>,2'-O-diacyladenosine-3'5'-cyclic phosphoric acid (DBc-AMP for short), which is treated with a salt exchanging agent (e.g., NaH CO3, etc.), to give an alkali metal salt of DBc-AMP. EFFECT:The desired compound can be prepared efficiently, economically and in high yield.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides 2'-0-diacyladenosine-s: 51
- This invention relates to an improved method for producing alkali metal cyclic phosphates, and provides an industrially advantageous method for producing 2'-〇-dibutyryladenosine-31,57-cyclic sodium phosphate salts, which are particularly useful as medicines and reagents. The purpose is to

In the following, the production of the sodium salt of dibutyryl compound will be explained as an example, and the following abbreviations will be used.

c-AMP: Adenosine-3',5'-cyclic phosphoric acid D
Bc-AMP: N',2'-0-dibutyryladenosine-8',5'-cyclic phosphoric acid OMc-AMP: 2'-0-monobutyryladenosine-3',5'-cyclic phosphoric acid NMC-AMP: ~6-Motsubu f-Lil 7denoshi>
-3',5'-Cyclic phosphoric acid Conventionally, the following production method is known for DBc-AMP sodium salt. Namely.

a) Heating c-AMP with butyric anhydride in the presence of a tertiary amine and a dehydrating agent (JP-A-52-89699).

b) Reacting c-AMP triethylamine salt with butyric anhydride in the presence of a deoxidizing agent (Biochim, Bio
-phys, Acta, 148 9 9-1
05 (1967).

c) Heat reaction of c-AMP sodium salt with butyric anhydride at a temperature of 70°C or higher (Japanese Patent Application Laid-Open No. 57-18698)
).

Among these known methods, the method using c-AMP triethylamine salt or c-AMP sodium salt as a starting material requires first producing anhydrous triethylamine salt or sodium salt from c-AMP. For example, c-AMP/triethylamine salt can be prepared by dissolving c-AMP in an aqueous triethylamine solution, reacting at room temperature, concentrating one reaction mixture to dryness under reduced pressure, adding anhydrous pyridine to this and drying again. The operation becomes complicated because the operation must be repeated to obtain an anhydride.

In addition, in the method using C-MP or C-AMP triethylamine salt as a starting material, the reaction product is DBc-AMP.
- It is a triethylamine salt type, and a salt exchange operation is essential to convert it into a useful sodium salt. For example, DBc-AMP/triethylamine salt is treated with a sodium-type cation exchange resin) to convert it to IJium salt, but since the ion exchange resin treatment solution is a dilute solution, a concentration operation is required and it becomes unstable. Bc-AMP・su)
The IJum salt decomposes during concentration to produce OMc-AMP-sodium salt or:JMc,-AMP sodium salt, resulting in a decrease in the purity of the target product.

As described above, all of the known methods have disadvantages such as the complicated H process and the decomposition of DBc-AMP/sodium salt during the post-treatment of the two reactions, resulting in a decrease in purity. It wasn't necessarily satisfying.

Therefore, as a result of intensive research, the present inventor found that in the reaction between c-AMP and acid anhydride, (1) it is not necessary to use c-AMP in the form of a salt, and (2) the presence of a tertiary amine is necessary. and (2) The inventors completed the present invention by discovering that the desired product can be easily obtained in the form of an alkali metal salt by adding a salt exchanger to the acylation reaction solution.

That is, in the present invention, adenosine-3',5'-cyclic phosphoric acid is heated with a carboxylic acid anhydride in the presence of a tertiary amine to form N6,2'-0-diacylazo/syn-3',5'.
-By producing cyclic phosphoric acid and then reacting this with a salt exchanger, 2'-0-diacyladenosine-
This is a method for producing a 3', 5/-9 alkali metal phosphate.

To describe the present invention in more detail, e-AMP is heated with 2 to 6 times the mole of carboxylic acid anhydride 9, for example, butyric anhydride, in the presence of 1 to 3 times the mole of a tertiary amine 17) without a solvent or in a solvent. This will produce a diacylated product. This is confirmed by analyzing the substances present in the reaction solution over time using high performance liquid chromatography. -As an example.

Charts of high performance liquid chromatography after 15 minutes and 30 minutes when c-AMP 1.659 + 3.17 g of rubutyric anhydride and 1.02 g of triethylamine were heated and stirred at 140°C are shown in A and B of the drawing. . In the drawing, a represents c A M P + b OMc-AMP, and s represents an internal standard substance (β-naphthalenesulfonic acid). From this drawing, it can be seen that the raw material c-AMP and the intermediate product OM c -A MP that were present after 15 minutes disappeared after 30 minutes.

It is recognized that OB c -A and MP are produced at a high rate.

This reaction proceeds without solvent, but ethyl butyrate and
It is also possible to use aliphatic esters such as isopropyl acetate, butyl acetate.

As the tertiary amine, triethylamine is usually preferred, but trimethylamine, tripropylamine, tributylamine, etc., or cyclic tertiary amines such as pyridine, picoline, etc. can also be used.

The reaction conditions vary depending on whether or not a solvent is used and the number of moles of the tertiary amine and acid anhydride, such as butyric anhydride.
0-20 hours at 0-150°C, preferably 90-20 hours
It is preferable to carry out the reaction at 120°C for about 1 to 5 hours until OMc-AMP disappears.

By adding a salt exchanger to this reaction mixture and causing the reaction, N6,2'-〇-diacyl c-AMP can be obtained as a desired salt. What is the reaction?

It is appropriate to carry out heating until the salt exchanger is dissolved, and usually 1 to 2 hours is sufficient.

9 As a salt exchange agent, 1) usually hydrogen carbonate, IJium is preferred, but sodium iodide, sodium carbonate, sodium methylate, sodium butyrate, sodium acetate, etc. may also be used.

The alkali metal salt of diacyl c-A MP produced can be isolated and purified by appropriately treating the reaction mixture.

That is, in the case of DBc-AMP sodium salt, crude crystals are precipitated by adding an appropriate amount of a mixed solvent of Improvyl alcohol doisoprobyl ether or aqueous tetrahydrofuran to the reaction mixture. Dissolve this crude product in a small amount of water (less than 3 cups per liter), add 1.2 g of tetrahydrofuran,
It is appropriate to add an appropriate amount of = dimethoxyethane, 1,3-dioxolane, acetonitrile or propionitrile for recrystallization. Among them, tetrahydrofuran, 1,2-dimethoxyethane or 1,3-dioxolane are excellent.

Further, a mixed solvent of these and methyl ethyl ketone is also industrially excellent, and the most preferred is a combination of tetrahydrofuran and methyl ethyl ketone or tetrahydrofuran, which makes it possible to obtain sufficiently purified DBc-AMP sodium salt.

The present invention has made it possible to produce DBc-AMP sodium salt efficiently and with high yield, whereas conventional operations were complicated and unsatisfactory. ,Economic.

This provides an industrially superior method.

Example 1 C'-A1. (Pa. 29, add 6.83!7 of butyric anhydride and 2.027 of triethylamine,
Stir at ~120°C for 2 hours. Next.

Add 0.849% sodium hydrogen carbonate to the reaction solution and add 1% at the same temperature.
Stir for an hour. When the reaction solution is cooled and 130 tnl of 1.5% aqueous tetrahydrofuran is added, crystals are precipitated. The crystals were collected by filtration, recrystallized from 1.5% hydrated tetrahydrofuran, 150% of 20-furan, removed from oil, and dried.
AMP sodium salt 3.539 (yield □71 no 9%)
is obtained.

The IR of this product completely matches that of the standard sample of DBc-AMP sodium salt synthesized separately, and the analysis value by high performance liquid chromatography shows that the purity is 99.1% and impurities are OMc.
-AMP/sodium salt 0.25%, NMC=A1. l
P. Sodium salt is 0°21%.

Example 2 To cmAMP8.009, 5.77 cm of butyric anhydride and 2.309 cm of triethylamine were added and
Stir 4M at 120°C for 2 hours at rt. Add butyric acid to the reaction solution using a V-shaped tube.1. Add ox9 and stir at the same temperature for 1 hour. 8 mJ of isopropyl alcohol and then 6° of isopropyl ether are added to the reaction mixture. The precipitated crystals were collected by filtration, dried in a desiccator, dissolved in 2frLt of water, recrystallized from 130% tetrahydrofuran, collected by filtration, and dried to give DBc-AMP-sodium salt s,so
g (yield 73.7%) is obtained. The analysis value of this product by high performance liquid chromatography is - purity 98.5%.

Impurities are OMc-AMP sodium salt o, 16%, N
Mc-AMP-sodium salt 0.06%.

[Brief explanation of the drawing]

The drawing is a chart of fi1m liquid chromatography.

Claims (1)

[Claims] Azo/Syn-3: 51- M-phosphoric acid is heated with carboxylic acid anhydride in the presence of a tertiary amine to produce 2'-〇-diacyladenosine-sr, 5/-cyclic phosphoric acid. ~6,2'-'0-diacyladenosine-s characterized by reacting the compound with a salt exchanger.
',r,! -Production method of cyclic alkali metal phosphate