BG60756B2 - Difluoroantiviral compounds and their intermediate compounds - Google Patents

Abstract

The invention relates to 2,2-difluoro-2-deoxycarbohydrate used for the preparation of antiviral nucleosides of a suitable structure.

Description

1. Field of the Invention

This invention relates to the field of pharmaceutical chemistry and provides novel difluorocarbohydrate and novel antiviral nucleosides, obtained by coupling the new carbohydrate with suitable bases.

2. Background of the invention

It is known that antiviral drugs can be found in the nucleoside group. For example, 5- (2-bromovinyl) -2'-deoxyuridine is known to be a potential agent against herpes virus, De-Clercq et al., Proc. Natl. Acad. Sci. U.S.A. 76, 2947-51 (1979). Watanabe et al. have described a number of nucleosides prepared by coupling 2-fluoro-2-deoxyarabinofuranose with cytosine bases and thiamine groups; 5-Iodocytosine is their most preferred base, J. Med. Chem. 22, 21-24 (1979), and U.S. Pat. patent no. 4 211 773.

A compound that can be described as an acyclic nucleoside, 9- (2-hydroxyethoxymethyl) guanine, is a potential antiviral agent, especially useful against herpes viruses and has been the subject of a symposium whose materials include

Ί

US 4 808 614 published in a special issue of the American Journal of Medicine, July 1982.

fluorinated carbohydrates have been studied previously. They have been studied by Penglis in Advances in Carbohydrate Chemistry and Biochemistry 38, 195-285 (1981). 2,2-Difluorohexose is described by Adamson et al., Carbohydrate Research 18, 345-47 (1971). Wriglit u Taylor, Carbohydrate Research 6, 347-54 (1968) examined the synthesis of 9- (3-deoxy-3-fluoro-a-arabinofuranosyl) adenine.

Recently, the total synthesis of carbohydrates has been the subject of research and several publications have emerged. Synthesis requires stereospecific methods, using asymmetric epoxidation and asymmetric aldol reactions, Masamune, Sharpless et al., J. Org. Chem. 47, 1373-81 (1982).

SUMMARY OF THE INVENTION

The invention provides difluorodeoxy carbohydrate of formula

Y0H ₂ C o

YO where X is a hydroxy or leaving group; and the Y groups, independently of one another, are hydrogen or hydroxy protecting groups.

The invention also provides nucleosides of formula

US 4 808 614 non> c ο

> --—-- f- F

HO F where R is a base with one of the formulas

CH = CHR ³

where

R 1 is hydrogen, methyl, bromine, fluorine, chlorine or iodine;

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R2 is xugpokcu or amino;

R3 is hydrogen, bromine, chlorine or iodine.

The invention further includes a process for preparing a lactone of formula non ₂ with o

HO F which consists in the hydrolysis under very mild conditions of alkyl 3-dioxolanyl-2,2-difluoro-3-hydroxypropionate of the formula

Another aspect of the invention are pharmaceutical compositions comprising a nucleoside of the above formula and a pharmaceutically acceptable carrier, diluent or excipient, as well as a method of treating viral infections in mammals using one of the present new compounds.

Description of preferred cases

All temperatures in this description. Celsius. The fluids given in the Structural Formulas above are given in degrees by volume, do not show

US 4,808,614 the chemical chemistry of the compounds of the present invention. Compounds of all configurations are considered to be useful and their stereochemistry is not limited. However, it is preferred that the carbohydrate has the configuration of a natural ribose such as the following

(It is also preferred that the configuration of the link between the ribose and the base be as follows:

F _h Chemist pharmacists are understood to be aware of the basics used in the synthesis of antiviral nucleosides of the present invention, but the following specific nucleosides are mentioned herein to ensure that each reader understands the type of antiviral compounds that this invention provides.

1- (5-methyl-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (5-bromo-2,4-deoxy-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

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1- (5-chloro-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (5-Halo-2,4-fluoro-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (4-amino-5-chloro-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

- (4-amino-5-bromo-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

- (4-Amino-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (4-amino-5-iodo-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (4-amino-5-methyl-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- [5- (2-Bromovinyl) -4-hydroxy-2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- [4-amino-5- (2-bromovinyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- [4-amino-5- (2-iodoisyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- [5- (2-Chlorovinyl) -4-hydroxy-2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- [4-hydroxy-5- (2-iodinovinyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- [4-amino-5- (2-chlorovinyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluororibose;

1- (2-amino-6-oxo-1H, 9H-purin-9-yl) -2-deoxy-2,2difluororibose;

1- (6-amino-9H-purin-9-yl) -2-deoxy-2,2-difluororibose;

1- (5-fluoro-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

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1- (2,4-guoxo-1H, 3H-nitro-1H-yl-1-yl) -2-deoxy-2,2difluoroxylose;

1- (5-bromo-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

1- (5-chloro-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

1- (5-iodo-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

1- (4-amino-5-fluoro-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose;

1- (4-amino-5-chloro-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

1- (4-amino-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

1- (4-amino-5-fluoro-2-oxo-N-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose;

B (4-amino-5-mesyl-2-oxo-1H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose

1- [5- (2-Bromovinyl) -4-hydroxy-2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose;

1- [4-amino-5- (2-bromovinyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose;

1- [4-amino-5- (2-iodinovin) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose ',

1- [5- (2-Chlorovinyl) -4-hydroxy-2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose;

1- [4-hydroxy-5- (2-iodinovin) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose;

1- [4-amino-5- (2-chlorovinyl) -2-oxo-1H-pyrimidin-1-yl] -2-deoxy-2,2-difluoroxylose;

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1- (2-amino-6-oxo-1H, 9H-purin-9-yl) -2-deoxy-2,2d fluoroxylose a 1-> 1- (6-amino-9H-purin-9-yl) -2 - deoxy-2,2-difluoroxylose.

It will be appreciated that the reactions in which the novel 2-deoxy-2,2difluorocarbohydrate of this invention kunnel with the bases are often of such a nature that the hydroxy groups need to be protected from reacting with the base or from degradation in any way. The protecting groups are selected from the groups used in organic synthesis for this purpose. Chemists are accustomed to choosing groups that can be effectively put in place of hydroxy groups and that can be easily separated when the desired reaction is complete. Suitable groups are described in 6 ordinary textbooks, such as section 3 of Protective Groups in Organic Chemistry, McOmie, Ed., Plenum Press, New York (1973); and Section 2 of Protective Groups in Organic Synthesis, Green, John Wiley & Sons, New York (1981).

Typical hydroxy-protecting groups are formyl, 2-chloroacetyl, benzyl »diphenyl, trifluoromethyl, 4-nitrobenzyl, phenoxycarbonyl, t-butyl, methoxymethyl, ethyl, tetrahydrocarbonyl, methoxyethanol; similar. Silyl hydroxy-protecting groups are often more convenient because most of them are easily cleaved by contact with water or alcohol. Such a group is trimethylsilyl as well as isopropyldimethylsilyl, methyldiisopropylsilyl, triisopropylsilyl and the like. similar, the butyldimethylsilyl group is a special case and is preferably a protecting group in this synthesis; it splits harder and requires a reagent such as ο

US 4 808 614 hydrochloric acid to separate it from the hydroxy groups.

Ribose or xylose have a hydroxy group in the 1st position in their rings. In order for the carbohydrate of this invention to react with the base to produce the antiviral compounds of the invention, it is necessary to place the leaving group in the 1st position. The leaving groups used are those commonly used in organic synthesis. Preferred leaving groups are sulfonates, of which the most preferred is (* methanesulfonate; other typical leaving groups are toluenesulfonate, ethanesulfonate, isopropanesulfonate, 4methoxybenzenesulfonate, 4-nitrobenzenesulfonate, 2chlorobenzenesulfonate, 2chlorobenzenesulfonate, 2chlorobenzenesulfonate).

To ensure that the reader is aware, the following group of representative 2-deoxy-2,2 difluorocarbohydrates of the present invention is mentioned;

2-deoxy-2,2-difluororibose;

3,5-bis (trimethylsilyloxy) -2-deoxy-2,2-difluororibose;

3,5-dibenzyloxy-2-deoxy-2,2-difluororibose;

3,5-bis (chloroacetoxy) -2-deoxy-2,2-difluororibose;

3.5- bis (2-chlorobenzyloxy) -1-methanesulfonyloxy-2-deoxy-

2,2-difluororibose;

3,5-bis (4-nitrobenzyloxy) -1- (4-toluenesulfonyloxy) -2-deoxy-2,2-difluororibose;

1-chloro-3,5-bis (phenoxyacetoxy) - 1,2-deoxy-2,2difluoroxylose;

1- (2,4-dibromophenylsulfonyloxy) -3,5-bis (2,2dimethylpropionyloxy) -2-deoxy-2,2-difluoroxylose;

US 4 808 614

3,5-bis (benzyloxy) -1- (o-schulenesulfonyloxy) -2-deoxy-2,2difluoroxylose;

1-bromo-3,5-bis (methoxycarbonyloxy) - 1,2-deoxy-2,2difluoroxylose '

3,5-bis (allyloxycarbonyloxy) -1-chloro-1,2-deoxy-2,2difluoroxylose;

3,5-bis (benzyloxycarbonyloxy) -2-deoxy-2,2difluoroxylose;

1-bromo-3,5-bis (4-nitrobenzyloxycarbonyloxy) -1,2-deoxyI-

2,2-difluoroxylose;

1-bromo-3,5-bis (tetrahydroxyenyloxy) -1,2-deoxy-2,2difluororibose *, h

1-bromo-3,5-bis (isopropyldimethylsilyloxy) -1,2-deoxy-2,2difluororibose;

1- (2-chlorophenylsulfonyloxy) -3,5-bis (methoxymethoxy) -2deoxy-2,2-difluororibose;

3,5 - bis (benzyloxymethoxy) 2-deoxy-2,2-difluoro bose;

1- (4-iitrophenylsulfonyloxy) -3,5-bis (trityloxy) -2deoxy-2,2-difluororibose;

3,5-bis (allyloxy) -1-chloro-1,2-deoxy-2,2-difluororibose;

2- deoxy-2,2-difluoroxylose;

3,5-bis (trimethylsilyloxy) -2-deoxy-2,2-difluoroxylose;

3,5-dibenzyloxy-2-deoxy-2,2-difluoroxylose;

3,5-bis (chloroacetoxy) -2-deoxy-2,2-difluoroxylose;

3,5 - bis (2-chlorobenzyloxy) -1-thaisulfone.yloxy-2-deoxy-

2,2-difluoroxylose;

3,5-bis (4-nitrobenzyloxy) -1- (4-toluenesulfonyloxy) -2-deoxy-2,2-difluoroxylose;

- bromo - 3,5-bis (those trichloride nyloxy) -1,2-deoxy-2,2difluoroxylose;

US 4 808 614

1-bromo-3,5-bis (from propyldimethylsilyloxy) -1,2-ge zoxy-2,2difluoroxylose,

3,5-bis (1-Busyldiphenylsilyloxy) -2-deoxy-2,2difluororibose;

3.5-bis (formyloxy) -isopropylsulfonyloxy-deoxy-difluororibose;

3.5-bis (trichloroacetoxy) - 1-methanesulfonyloxy-2-deoxy-

2,2-difluororibose;

1-chloro-3,5-bis (phenoxyacetoxy) -1,2-deoxy-2,2difluororibose;

1- (2,4-dibromophenylsulfonyloxy) -3,5-bis (2,2dimethylpropionyloxy) -2-deoxy-2,2-difluororibose;

3.5-bis (benzyloxy) -1- (o-toluenesulfonyloxy) -2-deoxy-2,2difluororibose ',

1-bromo-3,5-bis (methoxycarbonyloxy) -1,2-deoxy-2,2difluororibose;

1- (2-chlorophenylsulfonyloxy) -3,5-bis (methoxymethoxy) -2deoxy-2,2-difluoroxylose, *

3,5-bis (benzyloxymethoxy) -2-deoxy-2,2-difluoroxylose;

1- (4-nitrophenylsulfonyloxy) -3,5-bis (trityloxy) -2deoxy-2,2-difluoroxylose;

3,5-bis (allyloxy) -1-chloro-1,2-deoxy-2,2-difluoroxylose;

3.5-bis (1-butyldiphenylsilyloxy) -2-deoxy-2,2difluoroxylose *,

3,5-bis (formyloxy) -1-isopropylsulfonyloxy-2-deoxy-2,2difluoroxylose;

3.5-bis (trichloroacetoxy) -1-methanesulfonyloxy-2-deoxy-

2,2-difluoroxylose;

3.5-bis (allyloxy arbonyloxy) - 1-chloro-1,2-de zoxy-2,2difluororibose;

US 4 808 614

3,5-bis (benzyloxycarbonyloxy) -2-deoxy-2,2difluororibose;

1-bromo-3,5-bis (4-nitrobenzyloxycarbonyloxy) -1,2-geosacc-

2,2-guflyopopubosis.

Carbohydrates are prepared by a process> starting with the reaction of D-glyceraldehyde ketonide of the formula

where and R 1 are independently C 1 -C 3 alkyl,; C 1 -C 4 alkyl bromodifluoroacetate, preferably ethyl ester.

A preferred glyceraldehyde ketonide is the acetonide, wherein R1 is both methyl, which was first published by Fischer and Baer, Helv. Chim. Acta. 17, 622 (1934). Ethyl bromodifluoroacetate was obtained for the first time by Morel and Dawans, Tet. 33, 1445 (1977). The ketonide and haloacetate are reacted in the presence of an active metal such as magnesium or preferably zinc. Activation is most easily obtained by applying ultrasonic energy to the reaction mixture. Activation thus compensates for the presence of a small amount of water in the reaction mixture and thus avoids the need to maintain anhydrous conditions and the need to obtain and carefully store activated metals. However, the metal can be activated by methods ₅ known in the art, if necessary. The most recommended

US 4 808 614 amount of metal is approximately the equimolar amount.

The reaction is carried out in ethers such as tetrahydrofuran and diethyl ether at moderate temperatures. However, other organic solvents that are inert to the reaction conditions, including halogenated alkanes such as chloroform, dichloromethane, trichloroethane and the like, may be administered. similar and aromatic solvents, including

S As benzene, toluene and xylene. Temperatures from about ambient to about 100 ° are suitable; temperatures from about ambient to about 80 ° are preferred. Economically acceptable yields are obtained at a reaction time ranging from about a few minutes to about a few hours. It should be noted that the reaction is exothermic and therefore it may be necessary to cool the mixture depending on the scale of the reaction and the rate at which it is added.

reagents. t

The product of the first reaction is alkyl 3-dioxolanyl-2,2difluoro-3-hydroxyproponate of the formula

The ratio of the intermediate 3-R-xugpokcu to its 3-S-xugpokcu enantiomer appears to be about 3: 1. 3-R

US 4 808 614 xugpokcu enantiomer has the appropriate stereochemistry. for the preparation of a naturally occurring ribose so that it is the desired Tennantiomeric product for the first step. The 3-R hydroxy enantiomer can be completely separated from the 3 S enantiomer by standard methods, for example by chromatography on silica gel, eluting with a solvent such as chloroform containing 0.5% methanol (v: v).

Hydroxypropionate in any form is hydrolyzed under very mild conditions to give the lactone form of the carbohydrate of formula

F

BUT F

Proper hydrolysis has been found to result in cleavage of the functional ketonide and, unexpectedly, also to cleavage of the ester group, producing lactone in one step. The hydrolysis reagent is preferably a slightly acidic substituted ion resin, most preferably Dowex 50W-X12 (Dow Chemical Company). It is possible to carry out the process with other soft hydrolysis reagents, but it is possible to obtain larger quantities of by-products. For example, an aqueous solution of acetic acid or other relatively strong acids such as propionic acid, formic acid, chloroacetic acid, oxalic acid and the like may be used for hydrolysis. similar.

The hydroxy groups of the lactone must be protected before its keto-oxygen is reduced. Are used

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ordinary reaction conditions depending on the nature of the selected protecting groups. For example, the butyldimethylsilyl group is most preferably administered in the form of its trifluoromethanesulfonate and the protective reaction is carried out in the presence of a base such as lutidine, pyridine and the like. similar. Acyl protecting groups such as acetyl, benzoyl and the like. such are provided by reacting the lactone with an acylating agent such as acyl chloride, bromide, cyanide or azide or with a suitable anhydride. Suitable interactions are with a basic solvent such as pyridine, quinoline or isoquinoline or with a tertiary amine solvent such as triethylamine, tributylamine, methylpiperidine and the like. similar. The reaction may also be carried out in an inert solvent to which an acid acceptor such as a tertiary amine is added. If necessary, acylating catalysts such as 4-dimethylaminopyridine or 4-pyrrolidinopyridine may be used in the reaction. The acylating reactions, which provide hydroxy protecting groups, are carried out at average temperatures in the range of -25 ° to 100 °. Such acylations can be carried out by acid-catalytic reactions of suitable carbocyclic acids in inert or anhydrous organic solvents. Acid catalysts such as sulfuric acid, polyphosphoric acid, methanesulfonic acid and the like are used.

Acylating protecting groups can also be provided by forming an appropriate ester of a suitable acid, such as esters. formed by known reagents such as dicyclohexylcarbodinamide, acylimidazoles,

US 4 808 614

nitrophenols, pentachlorophenol, N-hydroxysuccinimide and 1hydroxybenzotriazole.

Ether-type protecting groups are provided by reacting lactone with, for example, a suitable diazo compound such as diazomethane, phenyldiazomethane or silyldiazomethane. Such reactions are typically efficiently carried out in solvents, including esters such as ethyl acetate, halogenated solvents, for example dichloromethane and chloroform, and ethers, such as diethyl ether and tetrahydrofuran. The process is usually carried out at low temperatures from about -50 ° to about 0 °. Such ether-forming reactions may also be carried out with the aid of reagents such as trimethyloxosulfone hydroxide, trimethylsulfonic hydroxide and trimethylselene hydroxide in solvents such as dimethylsulfoxide, dimethylformamide, hexamethylphosphoramide, acetone, acetone, acetone, acetone similar.

The silyl protecting groups are coupled to hydroxy groups using conventional methods, such as reaction with a suitable silyl carboxamide or bis (substituted silyl) carboxamide or a suitably substituted silozane. Suitably substituted silyl methanesulfonates, toluenesulfonates and the like are also used. Typically, an equivalent amount of base is required in the reaction mixture, unless a reaction medium is used in the form of a basic solvent such as those mentioned above.

When the hydroxy groups are protected, the lactone oxygen is reduced to alcohol to form the protected 2-deoxy-2,2-difluororibose or xylose according to this invention. Most preferred reducing agent

US 4 808 614 agent is diisobutyl aluminum hydride used at low temperature in the range of about -100 ° to -20 °. It is necessary to carry out the reduction very carefully to avoid sharp reducing conditions which will cause the ring to break at the oxygen atom. Other metal hydrides, such as the widely used lithium aluminumH hydride, can be used for the reduction, but it is necessary to maintain a sufficiently low temperature and ensure the destruction of the hydride before the temperature rises to. that of the environment. A very low freezing point solvent may be used in the reduction step. Toluene. is suitable, but of course other solvents may be used, including lower alkanols and in particular ethanol, ethers such as diethyl ether and the like. similar.

A suitable leaving group should be placed in the 1st position of the carbohydrate in order to efficiently react with the base. A preferred leaving group is methanesulfonyl which is readily provided by reaction of methanesulfonyl chloride in the presence of an equivalent amount of a suitable acid acceptor such as triethylamine and the like. Other sulfonyl leaving groups are provided in the same way by reaction with a suitable sulfonyl halide.

When using a chloro or bromo leaving group, it is often appropriate to first obtain the 1-acetate derivative, for example by reacting with acetic anhydride or other source of acetyl groups, in the presence of an equivalent or greater amount of acid acceptor. The acetate group is then replaced by hydrogen bromide or hydrogen chloride at low temperature, such as from ca.

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-50 ° to about 0 °. Since the gaseous hydrogen halide tends to remove the protecting groups, in particular the silyl protecting groups, it is necessary to carry out this step at a sufficiently low temperature and to add the halogen hydrogen slowly in small portions.

The bases used for the preparation of the antiviral compounds of the present invention are well known to organic chemists and no explanation is needed for their synthesis. Primary amino groups present in some of the bases must be protected before the base is coupled with the carbohydrate. The usual amino protecting groups, including silyl groups, such as those mentioned above, as well as such typical groups as tbutoxycarbonyl, benzyloxycarbonyl, 4methoxybenzyloxycarbonyl, 4-tribenzyloxycarbonyl, formyl and the like are used. similar.

It is often advisable to convert the keto oxygen atoms to the bases in an enol form to make the bases more aromatic and thus facilitate the interaction of the base with the carbohydrate. It is most convenient to enolysis the oxygen atoms by providing silyl protecting groups for them. The conventional silyl protecting groups mentioned above are also used for this purpose.

The interaction between the protected carbohydrate and the base is preferably carried out exactly at elevated temperature in the range of from about 50 ° to about 200 °. However, relatively high boiling solvents for the reaction, such as dimethylformamide, dimethylacetamide,

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hexamethylphosphoramide υ and the like. If the coupling reaction is carried out under high pressure to prevent distillation of the low boiling solvent, an inert reaction solvent may be used.

The coupling reaction can be carried out at low temperatures if a reaction initiator such as trifluoromethanesulfonyloxysilane is used.

The ordinary inert reaction solvents mentioned above may be used at temperatures ranging from about room temperature to about 100 °.

The last step of the reaction is the removal of the protecting groups. Most silyl protecting groups are easily separated by contact with water or alcohol, but the tbutyldimethylsilyl protecting group requires acidic conditions such as contact with gaseous halogen to remove it.

The acyl protecting groups are separated by simple hydrolysis with strong or medium strong bases, such as alkali metal hydroxides at temperatures from about room temperature to about 100 °. At least an equivalent amount of base is required for each protecting group. Such hydrolyses are conveniently carried out in hydroxyl solvents, in particular aqueous alkanols. However, the reactions can be carried out in any suitable solvent such as polyols, including ethylene glycol, ethers such as tetrahydrofuran and the like. similar ketones such as acetone and methyl ethyl ketone and other polar solvents such as dimethyl sulfoxide. The separation of acyl protecting groups may also be accomplished with other bases, for example sodium methoxide, potassium t-butoxide, hydrazine, hydroxylamine, ammonia, amides,

US 4,808,614 alkali metal and secondary amines such as diethylamine and the like. similar. Acyl protecting groups may also be separated by acid catalysts such as methanesulfonic acid, hydrochloric acid, bromoic acid, sulfuric acid or acid-substituted resins. Preferably, such hydrolysis is carried out at a relatively high temperature, such as the reflux temperature of the mixture, but temperatures as low as ambient temperature may be used when particularly strong acids are used.

Separation of the ether protecting groups is carried out by known methods, for example with ethanethiol and aluminum chloride.

None of the reaction steps requires unusual excess reagents. As is customary in organic syntheses, it is advisable and more economical to use a moderate excess in the range of 1.05 to 2 times the cheaper reagents to make sure that the more expensive ones are consumed.

The following preparations and examples illustrate the synthesis

of compounds of the present invention.

PREPARATION 1 ethyl 2,2-difluoro-3-hydroxy-3- (2,2-dimethyl-dioxolan-4yl) propionate

A small amount of solution containing 31.8 g of ethyl bromodifluoroacetate and 22.6 g of 4-formyl-2,2-dimethyldioxolane in 53 ml of tetrahydrofuran and 53 ml of diethyl ether was added to 10.2 g of activated zinc. Care should be taken to exclude water from the reaction mixture. Immediately after the first addition of zinc is activated, the solution begins to

US 4 808 614

is heated to reflux. The remainder of the solution is added dropwise at a rate that maintains a low reflux temperature during the addition of about 30 minutes. The mixture is then stirred at a low reflux temperature for about 30 minutes or more. The reaction mixture was poured into 200 ml of 1N hydrochloric acid and 200 g of ice and the mixture was stirred until all ice had melted. The aqueous mixture was then extracted 4 times with 70 ml portions of diethyl ether, and the organic layers were combined and washed with 50 ml of saturated aqueous sodium chloride solution and 50 ml of saturated aqueous sodium bicarbonate solution, dried with magnesium sulfate. and evaporated in vacuo to give 26 g of light yellow oil. The crude product was chromatographed on a column of 1000 g silica gel, eluting with chloroform containing 0.5% methanol to separate the basic 3-R-xugpokcu product from the secondary 3-hydroxy product. The ratio of the quantities of both products is about 3: 1; the by-product leaves the column first.

Evaporation of the fractions containing the 3-R-xugpokcu product afforded 12.6 g of the product in sufficiently pure form. It is determined by mass spectrometry showing a product weighing 239, which corresponds to the molecular weight of the desired product without a methyl group that is lost by the acetonide functional group in the spectrometric measurement. Nuclear magnetic resonance analysis of the 3-R-xugpokcu product at 90 MHz in CDCl3 showed characteristics 5 = 3.94-4.45 (m, 5H); 3.14 (d, J = 4.5 Hz, 1H); 1.2-1.47 (m, 9H).

⁴ Analysis of the same NMR procedure of the 3-S-xugpokcu product, of which 4.68 g were obtained by evaporation of

Λ ζ.

IJS 4 808 614 chromatographic fractions containing it show characteristics 3.75-4.47 (m, 6H); 2.95 (d, J = 8 Hz, 1H); 1.251.5 (m, 9H).

RECEIPT 2

2-deoxy-2,2-difluoro-1-oxoribose gr from the 3-R-xugpokcu product obtained by a synthesis similar to that in Preparation 1 was dissolved in 500 ml of methanol and 250 ml of water and 250 g of Dowex 50W resin were added. X12.

The mixture was stirred at room temperature for 4 days and then the mixture was filtered through a pad of diatomaceous earth. The filtrate was evaporated to dryness in vacuo to give 33.0 g of the desired product, which was identified by a 90 MHz NMR assay in CD3OD: 8 = 3.6-4.6 (series m, 4H); 4.8 (bs, 2H).

RECEIPT 3

3,5-bis (1-butyldimethylsilyloxy) -2-deoxy-2,2-difluoro-1-oxoribose

To 13 g of the product obtained in Preparation 2 was added 60 ml of dichloromethane, 22.5 ml of 2,6-lutidine and 48.2 ml of trifluoromethylsulfone loxy t-butyldimethylsilane, in the presence of nitrogen and under slight cooling, to keep the temperature below 25 ° . By 15 min after mixing the reagents, the reaction becomes quite exothermic and the mixture is diluted and easily stirred. The mixture was stirred overnight. The mixture was diluted with 150 ml of ethyl acetate and washed successively with 40 ml of 1N hydrochloric acid, 40 ml of saturated aqueous sodium bicarbonate solution and 40 ml of saturated aqueous sodium chloride solution. It was then dried with magnesium sulfate and evaporated to dryness under dry conditions

US 4 808 614 vacuum to obtain 32.1 g of crude product to be chromatographed: c. 260 g of 100 mei silica gel, eluting with a 10: 1 mixture of chloroform and diethyl ether (v: v). The fractions containing the desired product were combined and evaporated in vacuo to give 7.8 g of pure product. The other fractions were collected and evaporated to give another 10 g of impure product that was no longer purified. The pure product analysis shows the following results:

IR (exact) 1820 cm-L NMR (CDCl3 * 90 ΜΗζ) δ = 0.1-0.22 (m, 12H); 0.83-0.98 (m, 18H); 3.63-4.7 (series of m, 4H); mass spectrometry m / e = 339 = P-t-butyl.

EXAMPLE 1

3,5-bisH-bipyldimethylsilyl) -2-deoxy-2,2-difluororibose

10.3 g of 3,5-bis (1-butyldimethylsilyloxy) -2-deoxy-

The 2,2-difluoro-1-oxoribose, obtained in a similar manner to Preparation 3, was dissolved in 120 ml of anhydrous toluene and cooled to -84 °. To the solution was added 26 g of diisobutyl aluminum hydride for 20 min with constant stirring. The temperature of the reaction mixture was maintained below -65 ° throughout. Two hours after the first addition of hydride, the reaction mixture was cooled sharply with methanol at -20 °, additional cold methanol was added until gas evolution ceased. The mixture was allowed to warm slowly to ambient temperature and washed with N 100 ml of 0.1Ν hydrochloric acid. The aqueous layer was then washed with 100 ml of diethyl ether and then 3 times with 50 ml of diethyl ether each time. The organic layers were combined, washed with 100 ml of saturated aqueous sodium bicarbonate solution, dried with magnesium sulfate and evaporated under

US 4 808 614 vacuum dry to obtain 8.2 g of the desired product in crude form.

If necessary, this material can be chromatographed on silica gel (25 g of silica / 1 g of crude product) using 100% dichloromethane for elution. NMR (CDCl3, 90 MHz) δ = 0.1-0.24 (m, 12H); 0.85-1.0 (m, 18H); 3.33-4.63 (m series, 5H); 5.0-5.27 (dd, 1H); mass spectrometry m / e = 341 = P - 1 - butyl; = + 25.1 °.

EXAMPLE 2

3,5-bis (1-butyldimethylsilyloxy) -1-methanesulfonyloxy-2- de zoxy-2,2-difluororibose

0.5 g of 3,5-bis (1-butyldimethylsilyloxy) -2-deoxy-2,2-

the difluororibose is dissolved in 5 ml of anhydrous dichloromethane and 0.17 g of triethylamine. 0.11 ml of mixed sulfonyl chloride was added to the solution under slight cooling. After stirring for three hours, in the presence of nitrogen at about 25 ° C, the mixture was evaporated in vacuo and the precipitate was collected in 10 ml of ethyl acetate. The solution was extracted with 3 ml of saturated aqueous sodium bicarbonate solution and then successively with 3 ml of 1N hydrochloric acid, 3 ml of water and 3 ml of saturated aqueous sodium chloride solution. The organic solution was then dried with sodium sulfate and concentrated in vacuo to give 0.59 g of the desired product, NMR (CDCl 3, 90 MHz) 80.05-0.16 (m, 12H); 0.78-0.90 (m, 18H); 3.0 (s, 3H); 3.634.59 (m series, 4H); 5.67-5.9 (dd, 1H); mass spectrometry m / e = 419 = P-1-butyl.

EXAMPLE 3

1- (5-methyl-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

US 4 808 614

To 2.59 g of 3,5-bis (L-butyldimethylsilyloxy) -1-methanesulfonloxy-2-deoxy-2,2-difluororibose are added 1.60 g of 5-methyl-2,4-bis (trimethylsilyloxy) pyrimidia and 45 ml of dry 1,2-dichloroethane. To this mixture was added 1.45 g of trifluoromethanesulfonyloxytrimethylsilane and the pure solution was stirred in the presence of nitrogen and refluxed for about 2-3 hours. It is then cooled to ambient temperature and 1.35 ml of methanol is added and the suspension is stirred for 30 minutes. The precipitate is filtered and the filtrate is reduced to half its volume in vacuo and then diluted with an equivalent volume of dichloromethane. The solution was washed with saturated aqueous sodium bicarbonate solution and then with saturated aqueous sodium chloride solution and dried with anhydrous sodium sulfate. The solution was filtered and the filtrate was saturated with anhydrous hydrogen bromide. The reaction mixture was stirred for 30 min and then concentrated in vacuo. The precipitate was dissolved in methanol and the solution was evaporated to dryness in vacuo. The precipitate was dissolved in water and the solution was extracted twice with diethyl ether. The aqueous layer was then evaporated to dryness. The precipitate was collected in ethanol and evaporated repeatedly until all the water was combined in an azeotropic mixture. 1 g of crude product is obtained, which is chromatographed on 30 g of Woelm silica gel (70-150 mesh), eluted with ethyl acetate to give 0.76 g of the desired product. It was again purified by recrystallization from ethyl acetate to give 0.37 g of a white, crystalline product. NMR (CDgOD, 90 MHz) δ 1.93 (s, 3H); 3.5-4.67 (m series, 4H); 4.83 (bs, 3H); 6.3 (t, J = 9 Hz, 1H); 7.47 (m, 1H); mass spectrometry m / e = 278 = Parent.

US 4 808 614

EXAMPLE 4

1- (5-megpyl-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

5.4 g of 3,5-bis (1-butyldimethylsilyloxy) -1-methanesulfonyloxy-2-deoxy-2,2-difluororibose and 5.4 g of 5-methyl-2,4-bis (trimethylsilyloxy) pyrimidine are mixed and heated in the presence of nitrogen by stirring at 100 ° for 1 hour and then at 150 ° for 1 hour. The mixture was then cooled to ambient temperature and diluted with 25 ml water and 10 ml methanol. The suspension was filtered through a pad of diatomaceous earth and the precipitate on the filter was washed with acetone. The combined filtrate was evaporated in vacuo to give 5.3 g of an oily precipitate. The precipitate was dissolved in 10 ml of acetone and passed through 4.5 cm filled with 80 g of silica gel. Elute with a mixture of dichloromethane: methanol: triethylamine = 15: 1: 1.

The first 100 ml of eluent was removed and the next 300 ml was evaporated in vacuo to give 4.1 g of crude product which was dissolved in 40 ml of acetone. Hydrogen chloride was bubbled through the solution for 1 hour and then bubbled with hydrogen bromide for another 1 hour. The solution was evaporated at 62 ° to afford

4.4 g dark, oily product.

The above product was dissolved in 10 ml of a warm mixture of dichloromethane: acetic acid = 3: 1 and passed through a 4.5 cm column filled with 45 g of silica gel. The eluent used for the first 1000 ml is a mixture of dichloromethane and acetic acid (3: 1), then only acetic acid. Most of the desired product exits the column of fractions between 1000 and 1400 ml determined by thin layer

US 4 808 614

silica gel chromatography, dichloromethane: ethanol evaporated in vacuo, acetone and filtered to give an oil, chromatographed and chloroformed the product to give 300 parts in 5 evaporated under use. The mixture was also mixed in 15 ml of cold (1.5: 1). The fractions were separated and the precipitate separated and the filtrate was distilled off in vacuo, which was dissolved in 5 ml on acetone and mixed υ (15: 1). is taken in mg semi-solid and ml acetone vacuum to prepare the ar silica gel fractions, vacuum, with a mixture containing to

This product is filtrate is mg light brown ml saturated aqueous water is evaporated under a substance.

i— filtered, 230 semi-solids were obtained. It was dissolved in 6 10 sodium bicarbonate solution and the solution was extracted twice with 15 ml portions of diethyl ether. The aqueous phase was then evaporated in vacuo, the precipitate suspended in acetone vacuum to give 140 mg of the desired product, filtered, and the filtrate was evaporated with a tan red-brown viscous oil.

The following example illustrates a preferred method of isolating a compound of the present invention.

EXAMPLE 5

1- (5-methyl-2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

To 80 g of 3,5-bis (1-butyldimethylsilyloxy) -1methanesulfonyloxy-2-deoxy-2,2-difluororibose in a nitrogen atmosphere were added 1.4 liters of freshly distilled methylene chloride and 49.5 g of 5-methyl-2,4-bis ( trimethylsilyloxy) pyrimidine. To this mixture was added 44.8 g of trifluoromethanesulfonyloxytriethylsilane and the reaction mixture was heated

US 4 808 614 reflux for approximately 3 1/4 hours.

The reaction mixture was stirred at room temperature overnight and 41.6 ml of methanol were added. The resulting mixture was stirred for approximately 30 min and the precipitated solid was collected by filtration, the filtrate was concentrated in vacuo at 45 ° to give a dark oil which was diluted in 500 ml of methylene chloride saturated with anhydrous hydrogen bromide. The resulting suspension was stirred for approximately 3 hours, after which the volatiles were removed in vacuo at 45 °. The residue was dissolved in 100 ml of S% - ^ene sodium bicarbonate and 100 ml of diethyl ether. The aqueous layer was separated and concentrated in vacuo at 50 ° to give a precipitate that was treated | three times with 1θά ml portions of hot ethyl acetate. The organic layers were combined and evaporated in vacuo at 45 ° to give a precipitate which was dissolved in 50 ml of water. This solution was chromatographed on 10 ml portions through a Waters Prep 500 reversed phase column using Water / methanol (v: v, 9: 1) as eluent to give 2.21 g of 1- (5-methyl) -

2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose. NMR (CDgOD, 90 MHz) δ 1.9 (s, 3H); 3.65-4.65 (m, 4H); 4.83 (s, 3H); 6.12 (dd, J = 7Hz, 12Hz, 1H); 7.70 (s, 4W; mass spectrometry m / e = 278 = p.

EXAMPLE 6

1- (5-iodo-2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

To a solution of 1.99 g of 3,5-bis-butyldimethylsilyloxy) 1-methanesulfonyloxy-2-deoxy-2,2-difluororibose in 35 ml of dry methylene chloride, 2.08 g of tri (trimethylsilyl) -5-iodocytosine and 1.11 g of cyanide were added under nitrogen. trifluoro29

US 4 808 614 Methanesulfonyloxytrimethylsilane. The reaction mixture was refluxed for approximately 16 hours and cooled to room temperature. To the mixture was added 5 ml of methanol and stirred for approximately 30 minutes. The precipitated solid was collected by filtration and the filtrate was evaporated to dryness in vacuo. The precipitate was dissolved in 20 ml of methylene chloride saturated with anhydrous hydrogen bromide to give a suspension which was stirred for approximately 3 hours at room temperature. The volatiles were evaporated under reduced pressure at 45 ° and the resulting precipitate was dissolved in 15 ml of water. The solution was neutralized to pH approximately 7 to 8 with 10% sodium bicarbonate and washed once with 10 ml of ethyl acetate. The aqueous layer was chromatographed over Whatman Prep ODS-3 reversed phase column in 2 ml portions using water / methanol (v: v, 9: 1) as eluent to give 30 mg 1- (5- iodo-2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose. NMR (CD3OD, 90 MHz) δ 3.47-4.66 (m, 4H), 4.78 (s, 4H), 6.14 (2e, J = 7Hz, 1H), 8.32 (s, 1H); mass spectrometry m / e = 389 = p.

EXAMPLE 7

1- (5-fluoro-2,4-dnoxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

Solution of 1.1 g of 3,5-bisH-butyldimethylsilyloxy) -1methanesulfonyloxy-2-deoxy-2,2-difluororibose, 0.83 g of 5fluoro-2,4-bis (trimethylsilyloxy) pyrimidine and 0.655 g of trifluoromethanesulfonyloxytrimethylsilane silane reflux for approximately 17 hours in the presence of nitrogen. The reaction mixture was cooled to room temperature and 3 ml was added

US 4 808 614 methanol. The resulting solution was stirred for approximately 30 min at room temperature and the precipitated solid was collected by filtration. The filtrate was evaporated to dryness in vacuo at 50 ° and the precipitate was dissolved in 15 ml of methylene chloride saturated with anhydrous hydrogen bromide. The resulting suspension was stirred for approximately 30 min and the volatiles were removed in vacuo at 45 °. The precipitate was dissolved in 15 ml of water and the aqueous solution was extracted once with 10 ml of ethyl acetate. The aqueous layer was neutralized with sodium carbonate to pH approximately 7 and the solution was evaporated to dryness in vacuo at 50 °. The precipitate was dissolved in about 6 ml of water and the resulting solution was chromatographed in 2 ml portions through Whatman ODS-3 50 cm reversed phase column using water as eluent to give 30 mg 1- (5- fluoro-2,4-dioxo-1H, 3H pyrimidin-1-yl) -2-deoxy-2,2-difluororibose nmr CD ₃ OD, 90 MHz) δ 3.63, -4.6 (t, 4H), 4.79 (s, 3H ), 6.04 (t, J = 7Hz, 1H), 8.07 (d, J = 6Hz, 1H); mass spectrometry m / e = 282 = p.

EXAMPLE 8

1- (2-Oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

In a nitrogen atmosphere, 48 g of b and c (tertiary meth and lc and (tp and methyl and lc and or l) - N - acetylcytosine. To this mixture was added 39.23 g of shrifluoromeshansulfonyloxytrimethylsilane and the resulting mixture was stirred at reflux for approximately 15 hours. The reaction mixture was cooled to room temperature and 16 ml of methanol were added.

US 4 808 614

The resulting solution was stirred for approximately 30 min and concentrated to about half of its original volume. The solution was cooled in ice and the precipitated solid was collected by filtration.

shake once with approximately 300

The filtrate is ml

10% ^t ^ iampue6 bicarbonate and once with &? 100 ml of brine, Organic layer

evaporated to dryness in vacuo at 45 ° and the precipitate was dissolved in 1.3 l of methanol saturated with ammonia. The resulting suspension was allowed to stir overnight at room temperature

I - temperature, and the volatiles were removed in vacuo at 45 °. Dissolve the precipitate in 275 ml of methanol and add 100 sp of Bio Rad resin ion (AG 50WX8). The suspension was stirred at room temperature overnight and the resin was collected by filtration. The resin was washed with 100 ml of methanol and suspended in 100 ml of methanol and 50 ml of concentrated ammonium hydroxide. The suspension containing

N resin, stirred vigorously for 15 min and the resin was collected by filtration. This procedure is repeated twice with methanol saturated with ammonia. The combined methanol filtrates were combined and evaporated at 45 ° in vacuo to give 13.8 g of solid. This material was chromatographed on a Waters Prep 500 C ^ ⁸ reversed phase column with water as eluent to afford 1.26 g of 1- (2oox-4-amino - 1H - pyridin-1-yl) -2 - de zoxy-2 , 2 difluororibose. NMR (CD3OD, 90 ΜΗζ) 0 3.7-4.65 (w, 4H),

4.83 (s, 4H), 5.97 (d, J = 8Hz 1H), 6.24 (t, J = 7Hz, 1H), 7.88 (d,

J = 8 Hz, 1H); mass spectrometry m / e = 263 = p.

EXAMPLE 9

1- (2-Oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluoroxylose

US 4 808 614

In a nitrogen atmosphere, 23 g of tris (trimethylsilyl) cytosine and 300 ml of methylene chloride were added to 23 g of 3,5-6uc (tbutyldimethylsilyloxy) -1-methanesulfonyloxy-2-deoxy2,2difluoroxylose. To this mixture was added 10.84 g of trifluoromethanesulfonyloxytrimethylsilane and the mixture was stirred.

reflux for approximately 16 hours. The mixture was cooled to room temperature and 20 ml of methanol were added. The solution was stirred vigorously for approximately 1 hour at room temperature and the precipitated solid was collected by filtration. To the organic layer was added 100 ml of water and the suspension was stirred vigorously for 30 minutes. The organic layer was separated and evaporated to dryness under reduced pressure to give 11.2 g of brown oil. The precipitate was dissolved in 97 ml of methanol, to which was added 33 g of the cation-substituted Bio Rad AG 50X8 resin. The suspension was stirred for approximately 16 hours at room temperature and the resin was collected by filtration. The resin was washed with 50 ml of methanol and stirred vigorously in a solution of 100 ml of methanol and 100 ml of ammonium hydroxide. This procedure was repeated twice and the collected filtrates were concentrated in vacuo at 50 ° to give 2.09 g of a yellow precipitate. The precipitate was suspended in 25 ml of water and stirred vigorously for 15 min. The insoluble precipitate was collected by filtration to obtain 0.25 g of substance designated compound A. The filtrate was concentrated in vacuo at 50 ° to give 0.86 g. of compound designated B. Compound A was dissolved in 20 ml of methanol and stirred for three days with Bio Rad AG 50WX8 resin at ambient temperature. The resin was filtered and suspended in 30 ml of methanol / ammonium hydroxide solution

US 4 808 614 (1: 1, v: v). The resin was filtered again, and the filtrate was concentrated in vacuo at 50 ° to give 0.14 g of 1- (2 deoxy-2,2-difluoro-p-O-xylofuranosyl) cytokine NMR (CD3OD, 90 MHz) δ 3.72-4.34 ( m, 4H), 4.78 (s, 4H), 6.17G (d, J = 15Hz, 1H), 7.78 (d, J = 8Hz, 1H); mass spectrometry m / e = 263 = p.

The compound indicated as B was chromatographed over Whatman 50 cm.ODS-3 reversed phase Prep column using water / methanol (v: v, 1: 1) as eluent to give 0.06 g 1- (2- deoxy-2,2-di, fluoro-α-0xylofuranosyl) cytosine. NMR (CDO3D, 90 ΜΗζ) δ 3.53-3.9 (m. 2H), 4.1-4.57 (m, 2H) 4.83 (s, 4H), 5.9 (d. J = 8HzJ 1H) 6.3! (d, J = 8 Hz, 1H); mass spectrometry m / e = 263 = p.

EXAMPLE 10

1- (2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

A solution of 0.19 g of 1- (2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2-difluororibose in glacial acetic acid and 4 ml of water was refluxed for approximately 24 hours. The reaction mixture was cooled to room temperature and the volatiles were removed in vacuo at a temperature in the range of about 60 to about 70 °. The precipitate was concentrated by evaporation several times with 5 ml of toluene. The precipitate was dissolved in 12 ml of methanol and the resulting solution was cooled in a salt / ice bath to approximately -15 °. The solution was saturated with anhydrous ammonia and stirred overnight at room temperature. The volatiles were evaporated under reduced pressure at 45 ° and the precipitate was suspended in 5 ml of hot water. The insoluble material was collected by filtration and the filtrate was chromatographed

US 4 808 614 through Whatman 50 cm Partisil ODS-3 reversed phase column using water / methanol (v: v, 9: 1) as eluent to obtain 0.05 µp of the product containing a small amount of reacted starting material. This reacted starting material was separated by passing a solution of the solid in approximately 5 ml of methylene chloride containing 10% by volume of methanol through a Waters Silica Separation Column. The eluent was evaporated in vacuo at 45 ° to give 0.036 g of 1- (2,4-dioxo-1H, 3H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose. NMR (CD3OD, 90 ΜΗζ) δ 3.54-4.48 (t, 4H), @ 4.83 (s, 3H), 5.69 (d, J = 8Iz, 1H), 6.10 (dd, J = 7Hz, 9Hz, 1H), 7.8 (d, J = 8 Hz, 1H); mass spectrometry m / e = 264 = p.

EXAMPLE 11

1- (5-methyl-2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose

In a nitrogen atmosphere, a solution of 1.86 g of 3.5-6uc (tbutyldimethylsilyloxy) -1-methanesulfonyloxy-2-deoxy-2,2difluororibose, 1.87 µt of tris (trimethylsilyl) cytosine and 1.34 g of trifluoromethanesulfonyloxytrimethylsilane. in 37 ml of dry methylene chloride was refluxed overnight. The reaction mixture was cooled to room temperature and 1 ml of methanol was added. The precipitated solid was collected by filtration and the filtrate was evaporated in vacuo at 45 °. Dissolve the precipitate in approximately 20 ml of water and concentrate this solution to approximately half of its original volume by evaporation in vacuo at 50 °. The precipitate formed was collected by vacuum filtration and the filtrate was evaporated in vacuo at 50 °. The precipitate was turned into powder several times with 10 ml portions of warm acetone. Organic extracts are also collected

US 4 808 614

Evaporation of the foot vacuum to 45 ° yielded 1.b7Tr ^ oil. This material was dissolved in 15 ml of methanol / water (v: v, 2: 1) and stirred overnight with 5 g of Bio Rad AG 50WX8 resin. The suspension was saturated with anhydrous ammonia and stirred for approximately 10 minutes. vacuum filtration and suspended in 30 ml of methanol / ammonia (1: 1, v: v). The slurry was stirred for approximately 10 minutes. The resin was collected by filtration and the major filtrates were collected and concentrated in vacuo at 50 °. to obtain 1.5 grams of orange oil. The oil was dissolved in 10 ml of water and this solution was chromatographed in 2 ml portions through Whatman Paftisil ODS-3 50 cm. Reversed phase Prep column using water as eluent to give 0.07 g 1- (5methyl- 2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose. NMR (CD3OD, 90 ΜΗζ) δ 1.94 (s, 3H), 3.534.62 (t, 4H), 4.5 (s, 411), 6.17 (t, J = 8Hz, 1H), 7.67 (s, 1H); mass spectrometry m / e = 277 = p.

In addition to the antiviral ability of the present compounds, certain compounds of this invention exhibit excellent oncological activity in standard tumor cases. A particularly preferred compound of such activity is the compound of Example 8, 1- (2-oxo-4-amino-1H-pyrimidin-1-yl) -2-deoxy-2,2difluororibose. 'This compound exhibits activity in various tumors L1210V lymphocytic leukemia, 6C3HED lymphosarcoma, CA-755 adenocarcinoma, P1534J lymphatic leukemia and X5563 plasma cell myeloma. When used for tumor chemotherapy, daily doses of the active compounds are in the range of about 0.1 to about 1200 mg / kg human weight. In the treatment of the elderly, it is preferable to apply within the limits of

US 4 808 614 about 0.1 to about 50 mg / kg in single or partial doses. The antiviral effect of the compounds of this invention is demonstrated by the proven in vitro test shown below. A representative compound of Examples 3 and 4 above was investigated and hereinafter referred to as the DFAT code term.

TEST 1

Green African Monkey Kidney (BSC-1) kidney cells

were grown in 2 25 cm Falcon flasks at 37 ° and in medium 199 with 5% inactivated fetal bovine serum (FBS), penicillin (150 units / ml) and streptomycin (150 μg / ml). When fused monolayers are formed, the supernatant growth medium is separated and an appropriately diluted pseudosubject virus or Herpes virus type 1 added to each flask. After one hour adsorption at

0.3 ml Simplex room temperature virus-infected cell membrane was coated with medium consisting of one 4acml% -aiionagar No.2 and one part double, strong medium 199 with FCS (fetal calf serum), penicillin and streptomycin and also containing crude DFAT at a concentration of 100 to 0.39 (µg / ml). A non-DFAT flask serves as a control flask. The stock solution of DFAT is liked in dimethyl sulfoxide at a concentration of 104 µg / ml. The flasks were incubated for 72 hours at 37 °. The spots that have been infected by the virus and where it has been reproduced show spots. A solution of 10% formalin and 2% sodium acetate was added to each flask to inactivate viruses to restore the cell envelope to the surface of the flask. Viral spots, regardless of size, are counted after staining the surrounding ones

US 4,808,614 cell regions crystalline violet. The number of spots is compared with the control number of drug concentration sites. The activity of the compound is expressed as a percentage of inhibited spots.

The results of these studies are shown in Tables 1 and 2.

TABLE 1

Percentage of inhibited spots at a given concentration (µg / ml) of DFAT in agar medium surrounding Herpes ____simplex, type 1________

100 50 25 12.5 6.25 3.12 1.56 0.78 0.39

96% 72% 53% 35% 15% 12% 0 8% 4%

TABLE 2

Percentage of inhibited spots at a given concentration (mcg / ml) of DFAT in agar medium surrounding a _____________ pseudovirus virus ___________________

100 50 25 12 6 3

DFAT 23% 18% 15% 12% 6% 5%

The antiviral nucleosides of the present invention are used to treat viral infections in the commonly used way of treating such pathological cases,

The compounds are effective in treating viral in general and in particular infections caused by herpes viruses.

The compounds are administered effectively orally, topically or parenterally. Generally, dosages ranging from about 5 mg / kg to about 500 mg / kg are used. It is more preferable

US 4 808 614 administer dosages ranging from about 10 mg / kg to about 100 mg / kg.

In medicine, the compounds are commonly used in the form of one of the pharmaceutical compositions of the present invention, which compositions are novel and important because of the presence of novel nucleosides in them. The formulation of the compositions is conventional and follows the usual practice of chemist pharmacists. When a nucleoside of the present invention is applied topically, it is made as a topical composition, such as a cream or ointment, to rub into diseased tissue. Creams are oil-phase and aqueous-phase emulsions in which nucleosides are either dissolved or suspended. Ointments are oily or waxy compositions in which the nucleoside may be dissolved but may be suspended if it is insoluble at the desired concentration.

The parenteral formulations are preferably formulated in such a way that the nucleoside is dissolved in an injection solution, but most nucleosides are in no way highly water soluble. Therefore, the parenteral composition is usually made as a dry powder of the nucleoside and physiologically acceptable suspending agents such as starch, sugar and the like. similar to which sterilized water is added. to obtain a suspension for injection. Parenteral compositions may be prepared in an aqueous medium containing moderate amounts of physiologically acceptable solvents such as propylene glycol and the like. such and such compositions may be capable of dissolving present nucleosides at acceptable concentrations.

US 4 808 614

Many types of orally administered compositions are commonly used, including single dosage forms such as tablets and capsules and liquid forms such as suspensions.

• hours

Generally, the dosage forms are preferred in pharmacy and are made in such a way as to provide the normal dose through one or a small number of tablets or capsules. The manufacture of tablets using suitable lubricants, binders and disintegrating agents has long been fully known to pharmacist chemists. Capsule production consists only of diluting the nucleoside with an inert powder in a suitable proportion, such as lactose, to obtain the required volume and fill the desired capsule. The formulation of suspensions for oral administration is accomplished by finely grinding the nucleoside and fully mixing it with a relatively viscous aqueous liquid. Viscosity is achieved by the addition of pharmaceutically acceptable thickening agents, including vegetable modified cellulose derivatives or gel-forming resins, chemical and the like.

Of course, suitable flavors are used to make the suspensions organoleptically acceptable.

Claims (14)

1. Nucleosides of the formula W0H, C where R is a base selected from the group consisting of US 4 808 614 where R 1 is hydrogen, methyl, bromine, fluorine, chlorine or iodine; R2 is hydroxy; R3 is hydrogen, bromine, chlorine or iodine. The nucleoside of claim 1, wherein the carbohydrate moiety is in ribose form. The nucleoside of claim 2, wherein the base is of formula The nucleoside of claim 1, wherein the base is of formula © The nucleoside of claim 4, wherein R 1 is methyl. The nucleoside of claim 3, wherein R 1 is methyl. US 4 808 614 The nucleoside of claim 1, wherein the base is c The nucleoside of claim 2, wherein the base is claim 7, wherein R 1 is iodine. The nucleoside of claim 8, wherein R1 is iodine. according to claim 7, wherein R1 is hydrogen according to claim 8, wherein R1 is hydrogen, the treatment of herpes viral infections in a mammal which is effective against a compound according to claim 7 9. 10. 11. 12. 13. mammals, need a herpes claim Nucleoside, Nucleoside, Nucleoside, Memoq for administration, such treatment, virus, amount of 1. US 4 808 614 A pharmaceutical composition for the treatment of herpes viral infections, comprising effectively, against the herpes virus, an amount of a compound according to claim 1 and a pharmaceutically acceptable carrier, diluent or excipient.