DE1244790B - Process for the production of the cancerostatically effective 5-azacytidine - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

C07d

German class: 12 ρ - 10/05

Number: 1 244 790

File number: C31878IVd / 12p

Filing date: January 15, 1964

Opened on: July 20, 1967

It is known to be effective chemotherapeutic agents that inhibit the growth of malignant cancerous tissue inhibit or prevent the development of a viral infection, such substances are added to the group the so-called antimetabolites belong, of which z. B. the 6-mercaptopurine, the 5-fluorouracil, the 6-azauridine, 5-iododeoxyuridine and hydroxybenzylbenzimidazole are important.

As a result of the research work, the inventors were able to determine that in general the 1-glycosyl-5-azacytosine, which have not yet been described in the literature, particularly thorough cancerostatic ones and have virological activity.

A substance very effective in the metabolism of nucleic acids rapidly growing biological Systems that intervene is mainly 5-azacytidine (l-jS-D-ribofuranosyl-5-azacytosine). The for this Test results obtained have since been published in Neoplasma, 11 (1964), No. 2, pp. 123 to 130, and in Experientia, 20, p. 202 (1964).

The object of the process according to the invention is to produce this latter substance in an economical manner. It uses reactions that are related to other compounds that however, are different from the compounds occurring in the process according to the invention, are known.

The process according to the invention for the preparation of the cancerostatically active 5-azacytidine of the formula NH ₂

Process for the production of the cancerostatically active 5-azacytidine

Applicant:

Ceskoslovenskä academy ved, Prague

Representative:

Dipl.-Ing. K. Siebert, patent attorney, Starnberg, Almeidaweg 12

Named as inventor:
Frantisek Sorm,
Alois Piskala, Prague

Claimed priority:

Czechoslovakia October 29, 1963 (5 916)

wise chloroform, with exclusion of moisture with equimolar amounts of an O-alkylisourea the general formula

HN = C (OR ¹ ) - NH ₂

HOCHo

XK

HO OH (1)

is characterized in that a 2 ', 3', 5 ^/ -Tri-O-acyl - /? - D-ribofuranosyl isocyanate of the general formula is used in a manner known per se

Acyl - Ο —CH ₂ N = C = O

wherein R ¹ denotes an alkyl radical having 1 to 4 carbon atoms, reacts at low temperature, the resulting! - ^ '^', S'-tri-O-acyl-ß-D-ribofuranosyl) -4-O-alkylisobiuret derivative of general formula

OR ¹

Acyl - O - CH ₂ NH-CO-N = C-NH ₂ / (K

Acyl -O Ο -acyl

VK ¹ heated with passing through a weak, dry inert gas stream with excess orthoformic acid methyl ester or ethyl ester, the

Acyl O O Acyl (2) temperature but lower than the boiling point of the

should be in the presence of an inert solvent, preferred orthoester used, and the so-

709 617/537

s-triazine derivative of the general formula

OR ¹

N N

Acyl - O - CH ₂

Acyl - Ο Ο - acyl

(5)

a few hours at room temperature with a saturated solution of ammonia in an alcohol treated.

The configuration of the glycosyl center does not change during the synthesis.

The acyl groups protecting the hydroxyls are split off at the same time when the OR ^ radical (5) is replaced by the NH _{2 group (1).}

In the following an example is given which explains the process according to the invention without the Procedure is limited to the example:

example 1

A solution of 0.65 g of O-methylisourea is added to a solution of 3.01 g of crude 2,3,5-tri-O-acetyl- / jD-ribofuranosyl isocyanate in 50 ml of dry chloroform, with cooling and stirring and with exclusion of atmospheric moisture given in 10 ml of dry chloroform. The solution is left to stand for 1 hour at laboratory temperature, is extracted twice with 20 ml of water, and after it has been dried with sodium sulfate, it is concentrated in vacuo to a thick syrup, which is dissolved in 10 ml of benzene and precipitated with 50 ml of petroleum ether. In this way 3.0 g, ie 80% of the glassy 1- (2 ', 3', 5'-tri-O-acetyl - /? - D-ribofuranosyl) -4 - methylisobiurets, A ä! ^IOH = 221 πΐμ (log f = 4.25).

3.75 g of l- (2 ^/, 3 ', 5'-Tri-O-acetyl / iD-ribofuranosyl) -4-methylisobiuret are dissolved hot in 30 ml Orthoameisensäureäthylester, and the solution is 10 hours at 135 to 14O ⁰ C heated in a slow, dry stream of nitrogen. After cooling, the solution is precipitated 75 ml of petroleum ether, and the deposited syrup is dissolved in 10 ml of dry benzene and again precipitated with 50 ml of petroleum ether. After decanting and drying in vacuo, the glassy l- (2 ', 3', 5'-tri-O-acetyl- / iD-ribofuranosyl) -4-methoxy-2-oxo-1,2-dihydro-1,3 , 5-triazine in a yield of 2.0 g, ie 52% with /. chsCN = 235 ΐημ (log f = 3.36), obtained.

3.85 g of the crude 1- (2 ', 3', 5'-tri-O-acetyl - / <? - D-ribofuranosyl) -4-methoxy-2-oxo-1,2-dihydro-1,3 , 5-triazine are dissolved in 30 ml of saturated at 0 ⁰ C methanolic ammonia solution and left for 12 hours in a sealed tube at room temperature. The precipitated crystalline l - /} - D-ribofuranosyl-5-azacytosine (5-azacytidine) melts at 227-230 ⁰ C (decomposition), yield 1.7 g, which is 70%.

Example 2

A solution of 5.40 g of crude 2,3,5-tri-O-benzoyl - ^ - D-ribofuranosylisqcyanat in 50 ml of anhydrous ether with cooling, stirring and exclusion of humidity with a solution of 0.74 g of 2-methylisourea in 20 ml of anhydrous acetone are added. The solution obtained in this way is stored at room temperature for 20 minutes, evaporated in vacuo to a thick syrup, the syrup is dissolved in 10 ml of ether and the solution is stored in the refrigerator overnight. The precipitated crystals are filtered off with suction, washed with a little ether and dried in a vacuum desiccator over concentrated sulfuric acid and potassium hydroxide. Yield 5.15 g (92% of theory) [based on 2-methylisourea] 1 - (2,3,5 - tri - O - benzoyl -beta-o- ribofuranosyl) -4-methylisobiuret, mp 169-170 ^0th C (ethanol).

A solution of 5.61 g of 1- (2,3,5-tri-O-benzoyl - /? - D-ribofuranosyl) -4-methylisobiuret in 50 ml of ethyl orthoformate is in a distillation apparatus and dried nitrogen is passed through for 15 hours to 135 heated to 140 ^{0 C.} The voluminous precipitate which precipitates out on cooling is filtered off with suction. The amorphous crude product becomes crystalline by trituration with 20 ml of anhydrous ether. It is suctioned off again, washed with a little anhydrous ether, dried in vacuo and recrystallized from anhydrous ethanol. When left to stand overnight, the pure product crystallizes out. It is filtered off with suction, washed with a little anhydrous ether and dried in vacuo. Yield 3.95 g (69% of theory) 1- (2,3,5-tri-O-benzoyl- / ti-D-ribofuranosyi) -4-methoxy-2-oxo-1,2-dihydro-1- , 3,5-triazine, m.p. 162 to 163 ° C (ethanol).

A mixture of 5.71 g of l- (2,3,5-tri-O-benzoyl- / fD-ribofuranosyl) -4-methoxy-2-oxo-1,2-dihydro-1,3,5-triazine and 40 ml of anhydrous methanol saturated with ammonia at 20 ° C. is stored in a closed vessel with occasional stirring at room temperature, the material being im. Goes into solution over the course of 1 hour. At this stage, the solution is inoculated and stored for a further hour at room temperature, the product separating out in crystalline form. The mixture is kept in the refrigerator overnight. The precipitated crystals are filtered off with suction, washed with anhydrous methanol and ether and dried in vacuo. Yield 1.96 g (80% of theory) of 5-Acacytidin, mp. 230-231 ⁰ C (decomposition).

Claims (1)

Claim: Process for the preparation of the cancerostatically active 5-azacytidine of the formula NB » HIGH ₂ N N HO OH characterized in that a 2 ', 3', 5'-tri-O-acyl- β - D - ribofuranosyl isocyanate of the general formula Acyl - Ο —CH ₂ N = C = O Acyl -O Ο -acyl in the presence of an inert solvent with exclusion of moisture with equimolar Amounts of an O-alkylisourea of the general formula HN = C (ORi) -NH ₂ wherein R ¹ denotes an alkyl radical having 1 to 4 carbon atoms, reacts at low temperature, the resulting 1- (2 ', 3', 5'-tri-O-acyl- / iD-ribofuranosyl) -4-O-alkylisobiuret derivative der general formula OR ¹ Acyl —O —CH ₂ NH-CO-N = C-NH ₂ heated with passing through a weak, dry stream of inert gas with excess orthoformate, but the temperature should be lower than the boiling point of the orthoester used, and the resulting s -Triazine derivative of the general formula OR ¹ N N Acyl - O - CH ₂ Acyl - O O - acyl a few hours at room temperature with a saturated solution of ammonia in one Alcohol treats. Acyl - O O - acyl Considered publications: A. R. Katritzky, Advances in heterocyclic Chemistry (1963), pp. 195, 196 and 203.