SI7713022A8 - Process for obtaining 5'-deoxy-5-fluoro-citidine and 5'-deoxy-5-fluoruridine, respectively - Google Patents

Description

PROCEDURE FOR PREPARATION OF 5 '-DESOXY-5-PLUORCITIDINE OR 5'-DEOXY-5-PLUORURIDINE

1. TECHNICAL FIELD

The present invention relates to the field of organic chemistry and pharmaceutical chemistry.

2. TECHNICAL PROBLEM

The invention includes a process for the preparation of novel pyrimidine nucleosides that can be used as anti-tumor agents, in particular a process for the preparation of 5'-deoxy-5fluorocytidine and 5'-deoxy-5-fluororidine, as well as their physiologically acceptable acid addition salts.

3. BACKGROUND OF THE INVENTION

The introduction of the 5'-deoxy substituent into pyrimidine nucleosides was described previously. Thus, Wempen et al., J.Amer, Chem.Soc. 82, 1624 (1960) described the synthesis of 5'-deoxyuridine, 5'-lezoxy5'-fluoro-cytidine, and 5'-deoxy-5'-fluorouridine. Japanese Pat. 49-116081 describes the preparation of 5'-deoxycytidine by reduction of the corresponding 5'-halo (Br iii I) or 5'-methyl or benzylmercaptan. No anti-tumor activity was attributed to any of the above-mentioned final products.

15324 * 0 9.JULH985

Palco and Pox, J. Med, Chem. 11, 148 (1968) describe the synthesis of 1- (5'-deoxy-β-D-arabinofuranosyl) cytosine. This compound was found to be inactive against L 1210 leukemia and Burkitt cell cultures, probably because such compound could not form a 5'-phosphorylated derivative.

Hein et al., Nu.deic AcldB Research j, 1125 (1976) also obtained 5'-deoxyuridine and 2 ', 5'-dideoxyuridine by alternating reduction methods. No biological activity was attributed to the products obtained.

Japanese Pat. 51-086481 describes the preparation of 2 ', 5'dideoxy-5-fluorouridine from the corresponding 2', 5'-dideoxy-5'j od compounds. The product has been shown to be an anti-khncerine inhibitor of Yoshida Sarcoma growth.

U.S. Patent No. No. 3,687,931 describes the preparation of 5'-deoxy5'-chloro or chromo nucleosides using triphenylphosphine, using carbon tetrachloride or carbon tetrabromide. The compounds have been found to have antibiotic, ant imetabolic and enzymatic inhibitory activity.

The compounds 5'-deoxyuridine and 2 ', 5'-dideoxy-5-fluorouridine are described in C.A. 76 (1972) 154079p and in Japanese Pat. 76-86481.

4. DESCRIPTION OF THE TECHNICAL PROBLEM CASE WINDOWS WITH PERFORMANCE

The compounds of the invention are readily prepared from 5-fluorocytidine and 5-fluouridine, respectively, by protecting both hydroxyl groups in the 2'- and 3'-position by trimming the isopropylidene ketal, which is achieved by treatment

5-fluorocytidine, or 5-fluororidine with organic sulfonic acid, e.g. p-toluenesulfonic acid in an isopropylidene ketalizing agent, e.g. 2,2-dimethoxypropane, in a suitable organic solvent, preferably a ketone such as acetone, at a temperature from about 0 ° C to 60 ° C, preferably at room temperature, and then by halogenation of the formed isopropylidene ketal in the 5'-position, by halogen.

Halogens are primarily bromine and iodine. The introduction of iodine can be effected, for example, by treatment with a learning agent such as methyltriphenoxyphosphonium iodide (MTPI) in a polar aprotic solvent such as * dimethylformamide (DMP) at a temperature between 0 and 100 ° C, preferably at room temperature. The introduction of bromine can be carried out with a brominating agent in a polar aprotic solvent such as DMF at a temperature between 10 and 100 ° C.

The 5'-halogen compound obtained is reduced to the corresponding 5'-deoxy compound, either by catalytic hydrogenation or by reducing agents such as complex metal hydrides.

The 5'-deoxy-2 ', 3'-O-isopropylidene 5-fluorocytidine or 5' -deoxy-2 ', 3' -0-isopropylidene-5-fluorouridine thus obtained is subjected to hydrolysis with 90% trifluoroacetic acid in for 1 hour at room temperature to give 5'-deoxy-5-fluorocytidine and 5'-deoxy-5-fluororidine, respectively.

If necessary, the resulting 5 ^z -deoxy-5-fluorocytidine and 5'-deoxy-5-fluororidine are converted into physiologically tolerable salts by treatment with a physiologically tolerable acid.

The term physiologically tolerable salts includes non-toxic salts forming 5'-deoxy-5-fluorocytidine and 5'-deoxy5-fluororidine with inorganic mineral acids _; i. organic acids, e.g. hydrochlorides, hydrobromides, phosphates, sulfates, nitrates, acetates, formates, maleates or benzoates.

5'-Deoxy-5-fluorocytidine and 5'-deoxy-5-fluorouridine as well as their physiologically acceptable acid addition salts act against Ehrlich's cancer and sarcoma 180 in mice within a wide dosage range, oral and parenteral. These compounds are therefore valuable anti-tumor agents and can be administered as pharmaceuticals in the form of pharmaceuticals with direct or sustained release of the active substance.

In mixtures with non-toxic, inert, solid or liquid carriers such as water, gelatin, gum arabic, milk sugar, starch, magnesium stearate, talc, vegetable oils, polyalkylene glycols, petroleum jelly, etc., which are suitable for enteral (eg oral) ) iii parenteral application. The pharmaceutical preparations may be in solid form, for example as tablets, dragees, suppositories, capsules, or in weekly form, for example as solutions, suspensions or emulsions. In certain cases, they are sterilized, that is, they contain other excipients such as preservatives, stabilizers, crosslinkers or emulsifiers, flavoring agents, salts to change osmotic pressure or buffers. The manufacture of pharmaceutical preparations can be performed in a manner that is routine for any person skilled in the art.

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Anti-tumor tests:

For administration to animals, the compounds were dissolved in water.

Sai.com 180-Test

18-20 g heavy white mice were implanted with the trocar small portions of the tumor (2Ό-30 mg) subcutaneously in the right groin area · Tumor sections were taken from Animals that were. carried tumors implanted 7-10 days earlier. Treatment was started on the day of implantation and continued once daily for 8 days. Animals were killed 8 days after implantation and tumors were excised and measured. The ratio of the average tumor weight of the untreated control group (C) to the average tumor weight of the treated group (T) was then calculated. Preventing t

tumor growth was given in prooents as (C-T). 100 / C. A compound was considered active for a given dose if growth inhibition was 50 percent or more.

Ehrlich's cancer test

The solid form of this tumor was obtained by subcutaneous implantation of 0.5 ml of one suspension of ascitic tumor cells diluted to 1-10 with sodium chloride solution. As a donor, one 18-20 g heavy white mouse served as a tumor implant 7-10 days earlier. Claiming and presentation of results was done in the manner described earlier.

The results obtained with the compounds described in this invention as well as with the two compounds of present practice are shown in Tables 1 and 2.

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The compound Dona χ β / mg / kg / Tested ftivotinjo · - 5S # · 5 '-Doxy-5-fluon- 400 i.p. 15 14 91 cytidine 200 24 23 72 100 16 16 65 50 24 23 57 25 15 15 45 800 p. o * 8 8 99 400 16 16 95 200 24 24 80 100 24 24 71 50 16 16 58 25 16 16 > 7 5 * -Dec5csi-5-n.uo3> · 400 and «pi 16 14 98 urldin 200 24 22 86 100 24 20 71 50 24 23 59 25 24 22 45 800 p. 8 8 99 400 16 16 98 200 16 16 90 100 15 15 70 50 8 8 56 25 8 8 27 5'-De <fcelpIrldin 200 i.p. 8 8 9 100 8 8 41 2 \ 5M) ideok3i-5- 400 I.p. 16 14 81 fluororidine 200 16 14 68 100 16 16 > 7 200 p.o. 8 8 34

The following examples give the starting materials and the product according to the invention.

EXAMPLE 1> A suspension of 2-fluorocytidine (92 g) and p-toluenesulfonic acid mono-hydrate (80 g) in acetone (1500 ml) and 2,2 µmethoxypropane (200 ml) was stirred for 2 hours at room temperature. Then solid sodium bicarbonate is added to the excess and stirred until acid is neutralized. The solid residue was filtered off and washed with acetone, and the filtrate and washing solution were evaporated to dryness. The residue was treated with hot ethyl acetate (700 ml) and, upon cooling, its crystallization began slowly. After standing overnight, the solid residue was washed with ethyl acetate and vacuum dried. Yield: 99.5 g (94%) of 2 ', 3'-0isopropylidene-5-fluorocytidine. One sample was recrystallized from methanol / ethyl acetate; m.p. 182-184 ° C.

A solution of 2 ', 3'-O-isopropylidene-5-fluorocytidine (32 g) and methyl-triphenoxy-phosphonium iodide (MTPI, · 60 g) in dimethyl formate (DMP, 300 ml dried) was left standing 1 1/2 hours at room temperature. Then methanol (100 ml) was added and the mixture was evaporated to oil consistency after 30 minutes.

Then 700 ml of ethyl acetate and 700 ml of 5% aqueous sodium thiosulphate solution were added and after shaking, the layers were separated. The ethyl acetate layer was washed once with aqueous thiosulphate solution (700 ml) and twice with water (700 ml) and evaporated to an oily residue, which was dissolved in hot ethyl acetate (400 ml). Hexane was added to the hot solution until crystallization began. After standing at 0 ° C, the crystalline precipitate was washed with hexane and dried in vacuo. After treatment with the mother liquor, a total of 30.1 g (69%) of 5 '-deoxy-5'-iodo-2', 3'-O-isopropylidene-5fluore itidine were obtained, m.p. Mp 192-194 ° C.

A solution of 5 '-deoxy-5' -j-2 ', 3 -'-O-isopropylidene-5 "fluorothio idine (48 g) in methanol (500 ml) and triethylamine (20 ml) was hydrogenated at room temperature and under normal pressure for 30 minutes in the presence of palladium-based coal (5%, 25 g) with constant stirring. The catalyst was removed by straining through Celite® the filtrate was evaporated to dryness and ethyl acetate (200'ml) was added to the residue. The crystals were allowed to stand overnight and the crystals were drained, the filtrate was evaporated to about 100 ml and left to stand again overnight. The recovered crystals were drained and the filtrate was evaporated to dryness in vacuo. 31 g (93%) of 5 * -deoxy-23'-O-isopropylidene-5-fluorocytidine * are obtained in the form of a foam. This substance is characterized by cropping crystalline picrate, m.p. Mp 168-17 ° C.

5'-deoxy-2 ', 3-2 N -isopropylidene-5-fluorocytidine (31 g) was treated with 40% trifluoroacetic acid (200 ml) for 40 minutes. The solution was evaporated to dryness and the residue was repeatedly evaporated with ethanol to remove water and trifluoroacetic acid and finally dissolved in ethyl acetate (400 ml). The solution was calcined using triethylamine and crystallization began after a few minutes. After standing overnight, the crystals were washed with ethyl acetate and dried in vacuo. 14 g (49%) of 5'-deoxy-5-fluorocytidine are obtained. An additional amount was obtained by chromatography on mother liquor on a silica gel column (600 g), eluting with ethyl acetate (4 L) and ethyl acetate / methanol mixture (5: 1, w / z 4 liters). The fractions of interest uparch were not dry and released over a Dowex 5C ^ column (H ⁺ - shape 2.3 x 60 cm). The column was then washed, first with water and finally with ammonia solution (IN). The ammonia fractions were evaporated to dryness and the residue was recrystallized from methanol. In this way another 6.7 g of 5'-desousi5-fluoroitidine is obtained. Total Yield: 20.7 g (78%); mp 209-211 ° C.

10.

EXAMPLE 2

Suspension of 5-fluorouridine (50 g) and p-toluenesulfonic acid monohydrate. (39.3 g) in acetone (750 ml) and 2,2-dimethoxy propane (94 ml) was stirred at room temperature for 50 minutes.

An excess of solid sodium bicarbonate of sodium was added to the clear solution and the mixture was stirred until it reacted neutrally. The solid residue was removed by filtration, washed with acetone and the filtrate evaporated to dryness. The solid was recrystallized from ethyl acetate (2 L) to give 48 g (83%) of 2 ', 3'-O-isopropylidene-5-fluororidine, m.p. Mp 196-197 ° C.

A solution of 2 ', 3'-O-isopropylidene-5-fluorouridine (46.4 g) in DMP (250 ml dry) was kept at room temperature for 50 minutes in contact with MTPI (86.7 g). Ethanol (200 ml) was then added and after 30 minutes the solution was evaporated and the oily residue was partitioned between ethyl acetate (1 L) and aqueous sodium thiosulphate (5%, 11). The ethyl acetate layer was washed twice with 1 l of water each, dried with sodium sulfate and evaporated to dryness.

The oily residue was crystallized from ethyl acetate (350 ml). 52.9 g (85%) of 5 '-isoxy-5 ^with- iodo-2,3, ^with -O-isopropylidene-5-fluorouridine, mp 202-203.5 ° C, are obtained.

A solution of 5 ^with -dezoksi-5 ^with the -j-2 ', 3'-O-isopropylidene-5-fluoruridina (24 g) in methanol (800 ml) and triethylamine (15 ml) hidrogenovan 90 minutes at room temperature under normal pressing, with constant stirring in the presence of palladium uiq on coal (12 g,

%). The catalyst was filtered off through Celite and washed with methanol, while the filtrate was evaporated to dryness and 200 ml of ethyl acetate were added to the residue and left to stand for 1 hour. The crystalline precipitate was removed by filtration, the filtrate was evaporated in half and allowed to stand overnight and once again treated. The resulting filtrate was evaporated to dryness in vacuo to give 5'-deoxy-2 ', 3' -O-isopropylidene-5-fluororidine / UV (CH 2 OH):

204 nm (£ 10,900) and 267 nm (£ 8670). IR (KBr): 3380, 3200, 1710, 1670 cm ^"1 /, the blade being operated Still 1 hour an aqueous solution of trifluoro / acetic acid (90%, 200 ml). The product was evaporated to dryness to remove water and trifluoroacetic

11.

acid, ethanol was added repeatedly and the solution was evaporated again with Han and the residue was crystallized from ethyl acetate. It was obtained

11.35 g of 5'-deoxy-5-fluororidine, m.p. Mp 189-190 ° C.

Dos. 9047/168 P-3022/77 9/07/1985

12NOWBOWS AND THE APPLICANT KNOWS A WAY FOR THE ECONOMIC USE OF THE APPLICATION FOUND. A suspension of 2-fluorocytidine (92 g) and p-toluenesulfonic acid mono-hydrate (80 g) in acetone (1500 ml) and 2,2dimethoxypropane (200 ml) was stirred for 2 hours at room temperature. Solid sodium bicarbonate is then added to the excess and stirred to neutralize the acid. The solid residue was filtered off and washed with acetone, and the filtrate and washing solution were evaporated to dryness. The residue was treated with hot ethyl acetate (700 ml) and crystallized slightly after cooling. After standing overnight, the solid residue was washed with ethyl acetate and vacuum dried. Yield: 99.5 g (94%) of 2 ', 3'-0isopropylidene-5-fluorocytidine. One sample was recrystallized from methanol / ethyl acetate '; m.p. 182-184 ° C.

A solution of 2 ', 3' -O-isopropylidene-5-fluorocytidine (32 g) and methyl-triphenoxy-phosphonium um iodide (MTPI, 60 g) in dimethyl formate (DMP, 300 ml dried) was allowed to stand 1 1/2 hours at room temperature. Then methanol (100 ml) was added and the mixture was evaporated to oil consistency after 30 minutes.

Then 700 ml of ethyl acetate and 700 ml of 5% aqueous sodium thiosulphate were added and, after shaking, the layers were separated. The ethyl acetate layer was washed once with aqueous thiosulphate solution (700 ml) and twice with water (700 ml) and evaporated to an oily residue, which was dissolved in hot ethyl acetate (400 ml). Hexane was added to the hot solution until crystallization began. After standing at 0 ° C, the crystalline precipitate was washed with hexane and dried in vacuo. After treatment with mother liquor, a total of 3θ, 1 g (69%) of 5 '-deoxy-5'-iodo-2', 3'-0-isopropylidene-5fluorocytidine were obtained, m.p. Mp 192-194 ° C.

LAWYER 'to «nn MIODRAO P. POPOVIC * 09.JULi19gQRDANA m. again

BELGRADE - TAKOVSKI 1 j Phone 339-442

A solution of 5'-deoxy-5'-of-2 ', 3 -'-0-isopropylidene-5fluorocytidine (48 g) in methanol (500 ml) and triethylamine (20 ml) was hydrogenated at room temperature and under normal pressure 30 minutes in the presence of palladium mind on coal (5%, 25 g) with constant stirring. The catalyst was removed by filtration through Celiteia®, the filtrate was evaporated to dryness and ethyl acetate (200 ml) was added to the residue. The crystals were allowed to stand overnight and the crystals were drained, the filtrate was evaporated to about 100 ml and left to stand again overnight. The recovered crystals were drained and the filtrate was evaporated to dryness in vacuo. 31 g (93%) of 5'-deoxy-2 ', 3'-O-isopropylidene-5-fluorocytidine are obtained as a foam. This substance is characterized by the formation of crystalline picrate, m.p. Mp 168-170 ° C.

5'-deoxy-23-S-isopropylidene-5-fluorocytidine (31 g) was treated with 90% trifluoroacetic acid (200 ml) for 40 minutes. The solution was evaporated to dryness and the residue was repeatedly evaporated with ethanol to remove water and trifluoroacetic acid and finally dissolved in ethyl acetate (400 ml). The solution was calcined using triethylamine and crystallization began after a few minutes. After standing overnight, the crystals were washed with ethyl acetate and dried in vacuo. 14 g (49%) of 5'-deoxy-5-fluorocytidine are obtained. An additional amount was obtained by chromatography on mother liquor on a silica gel column (600 g), eluting with ethyl acetate (4 L) and ethyl acetate / methanol mixture (5: 1, z / z 4 liters). The fractions of interest were evaporated to dryness and released over a column of Dowex 5C ^ (H ⁺ - shape 2.3 x 60 cm). The column was then washed, first with water and finally with ammonia solution (IN). The ammonia fractions were evaporated to dryness and the residue was recrystallized from methanol. An additional 6.7 g of 5'-deoxy5-fluorocytidine is thus obtained. Total Yield: 20.7 g (78%); mp 209-211 ° C.

5'-deoxy-5-fluorouridine is also obtained in an analogous manner.

Claims (1)

A process for the preparation of 5'-deoxy-5-fluorocytidine and 5'-deoxy-5-fluororidine as well as their physiologically acceptable acid addition salts, wherein 5'-deoxy-2 ', 3'-0- isopropylidene-5-fluorcitidin iii 5 * -dezoksi-2 ', 3''- 0-isopropylidene-5-fluoruridin hidrolizuju with 90% -nom trifluoro acetic acid at room temperature., and, if necessary, obtained was 5 ^r -dezoksi-5- fluorocytidine, or BO 5 '' - deoxy-5-fluorouridine is treated with physiologically acceptable acid.