CS272249B2 - Method of new substituted 2,4-diamino-5-cyanopirimidines production - Google Patents

Abstract

Derivs. of formula (I) and their salts are new. In (I) R1 = H, 1-6C alkyl, or 2-6C alkenyl or alkynyl; R2 = H, 1-10C alkyl or 3-6C cycloalkyl, or R1 and R2 are together (CH2)3, (CH2)4 or (CH2)5; R3 = H, COR5 or SO2R6; R4 = NH2, NHCOR5, NHSO2R6, -N=CR7-NR8R9 or -NH.CH=NR10; R5 = H, 1-12C alkyl, 3-6C cycloalkyl, 1-6C alkoxy, 1-3C perhaloalkyl or NR11R12; R6 = 1-6C alkyl; R7 = H, or 1-6C alkyl; R8 and R9 = H, or 1-6C alkyl, or together are (CH2)3, (CH2)4 or (CH2)5; R10 = SO2.R13 or -p(=x)(OR14)YR15; R11 and R12 are as R8 and R9; R13 = 1-10C alkyl (opt. substd. by 1-10 halo) or 3-6C cycloalkyl; R14 and R15 = 1-10C alkyl; X and Y = O or S. - Also new are the intermediates of formula (II), where R'1 and R'2 are as R1 and R2 but not together (CH2)3; n = 0-2. - Specifically claimed include (III); where A = H or EtCO; and Q = (a) or NEt2.

Description

(57) New compounds of formula I, wherein R 6 is hydrogen, C 1 -C 8 -alkyl, C 8 -C 8 -alkenyl or C 8 -C 8 -alkynyl, R 8 is hydrogen C 1 ^-C 10 -alkyl or C 1 ^-C 8 -alkyl- cycloalkyl or R R and Rg together are - (CH CH) - -, - (CHg) - - or - (CHg) - -, R znamená is hydrogen or -CO-R ^, R ^ is -NHg, -NH-CO- R 6 or -N = CH-N (R _g ) (R 6), R 6 is C 1 -C 6 -alkyne or CP 1 and R 8 and R 8 are independently C 1 -C 6 -alkyl, as well as and their salts are prepared by treating the compound of formula III with an amine HN (R 6) (R g), followed by formation of a compound of formula I wherein R 6 is hydrogen and R 6 is -NHg, i.e. the compound of formula I, optionally converted treatment with a compound introducing the group -CO-Rj or / a = CH-N (R g) (R 6) to form a compound of formula I wherein R 6 is -CO-R j or / and R 6 is -NH-CO-R 6 or -N = CH-N (R 8) (R 9), and the obtained compound is optionally converted to a salt The produced compounds of formula I have pesticidal properties and can be used vat as active ingredients of insecticidal and acaricidal compositions.

(13) B2 (51) Int. Cl. ⁵ C 07 D 239/48 A 01 N 43/54

(i) (III)

NHg (la)

I ί ⁴

The present invention relates to a process for the preparation of novel substituted 2,4-diamino-5-cyanopyrimidines and their salts. The compounds produced have valuable pesticidal properties and can be used as active ingredients of insecticidal and acaricidal compositions.

It has been found that the novel substituted 2,4-diamino-5-cyanopyrimidines of formula (I)

in which it represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an alkynyl group having 2 to 6 carbon atoms,

R 8 represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 3 to 6 carbon atoms, or

R ^ and Rg together are - (CH společně)) -, - (CHg) - - or - (CHg) g-,

R 6 represents a hydrogen atom or a group -CO-R 8,

3 ^ is -NHg, -NH-CO-Rg or -N (CH-NXRg) (Rg),

R 8 is C 1 -C 12 alkyl or trifluoromethyl;

R _a and R g are independently C 1 -C 6 alkyl, and their salts can be used to control pests and ectoparasites as active ingredients of insecticidal and acaricidal compositions.

In view of the advantageous effect, those compounds of formula (I) in which

R @ 1 represents a hydrogen atom or a C1 -C4 alkyl group,

R 8 is C 1 -C 4 alkyl or C 3 -C 6 cycloalkyl, or

R ^ and Rg together are - (CH CH) - - or - (CHg) g-,

R 1 represents a hydrogen atom,

R 6 is -NHg or -NH-CO-R 8a

R 8 represents a C 1 -C 4 alkyl or trifluoromethyl group, as well as salts of such compounds, and further compounds of formula I in which:

R @ 1 represents a hydrogen atom, a methyl group or an ethyl group,

R ₂ represents an alkyl group having 1 to 4 carbon atoms, or represents cyclopropyl,

R 6 represents a hydrogen atom,

R 6 is -NH 8 or -NH-CO-R 6, and

R 1 represents a C 1 -C 3 alkyl group, as well as salts thereof.

Since _r .K high insecticidal and acaricidal activity should be particularly emphasized compounds of the formula I in which

R ^ represents a hydrogen atom, a methyl group or an ethyl group,

R 8 represents a cyclopropyl group,

R 6 represents a hydrogen atom and

R4 is -NHg or -NH-CO-C8H4, and salts thereof.

Salts of the compounds of formula (X) are understood to be physiologically acceptable addition salts of inorganic and organic acids. Examples of inorganic acids include hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, phosphoric acid, phosphorous acid, nitric acid. Examples of organic acids include trifluoroacetic acid, trichloroacetic acid, formic acid, oxalic acid, succinic acid, maleic acid, lactic acid, glycolic acid, aconitic acid, citric acid, benzoic acid, benzenesulfonic acid, and methanesulfonic acid.

SUMMARY OF THE INVENTION The present invention provides a process for the preparation of the novel substituted 2,4-diamino-5-cyanopyrimidines of the aforementioned and defined Formula I, as well as salts thereof, by treating a compound of Formula III

with an amine of formula IV

HN 'in which ^{a R} 2 is as defined above, whereby a compound of formula I is formed, wherein R 1 is hydrogen and R 1 is -NHg, i.e. a compound of formula Ia

in which

R ^ and R R are as defined above, optionally converted by treatment with a compound introducing the group -CO-R ^ or / and = CH-N (Rg) (Rg) to give a compound of formula I wherein R ^ is -CO-R ^ ^ or / a

R 6 is -IJH-CO-R 6 or -N = CH-N (R g) (R g), wherein:

Rg, Rg and Rg are as defined above and the compound of formula I obtained is optionally converted to a salt.

The reaction of 2-chloro-4,6-diamino-5-cyanopyrimidine of formula III with an amine of formula IV is generally carried out at a temperature of about 10 to 100 ° C in organic solvents such as acetonitrile, tetrahydrofuran, dioxane or solvent mixtures; water.

The optional conversion of a compound of formula (Ia) to a compound of formula (I) in which R ^ has any of the meanings defined for a compound of formula (I) may be carried out by reacting the amino group at the 6-position of the pyrimidine ring with corresponding reagents known. Thus, for example, it is possible to react

6-Aminopyrimidine of formula Ia with Hal-CO-Rg compounds to give compounds of formula I which contain in the 6-position an -NH-CO-Rg group, wherein Hal represents a halogen atom, preferably a chlorine atom.

If a compound of the formula I is to be prepared in which R 6 is -N = CH-N (R g) (R g), then the 6-amino group is reacted with, for example, an acetal of the formula

RgO / ^H8

R ₆ 0

CH - Eating

R 8 represents an alkyl group having 1 to 6 carbon atoms and

Rg and Rg have the meanings given above.

In analogy to the corresponding reagents, the 4-aminopyrimidines of formula (Ia) can be prepared to give a compound of formula (I) wherein R R is -CO-Rg.

The acylations described above are carried out at atmospheric pressure in inert solvents or diluents in the presence of a base at temperatures of from 0 to 120 ° C, preferably at temperatures of 40 to 80 ° C. Suitable solvents and diluents are, for example: alkanes, such as n-pentane, as well as homologues thereof, including isomers to n-heptadecane; ethers such as diethyl ether, dipropyl ether, dibutyl ether, dimethoxyethane, dioxane or tetrahydrofuran; chlorinated hydrocarbons such as chloroform, methylene chloride, carbon tetrachloride or chlorobenzene; aromatic hydrocarbons such as benzene, toluene or xylenes. In addition, other inert solvents or diluents may be used in the process. Suitable bases to be used in these reactions are, for example, alkylamines, such as triethylamine or diisopropylethylamine, and furthermore pyridine or N-methylpyrrolidone.

The starting compound of formula III, i.e. 2-chloro-4,6-diamino-5-cyanopyrimidine, is known from Chem. Ber. However, it can be prepared according to the following scheme from the compound of formula VII by oxidation to a sulfone and exchange of the -SOgCH3 group with an -NHg group with ammonia.

(III)

A compound of formula VII can be prepared, for example, according to the following reaction scheme:

C = N

AND! - CSH i »I

CH, -S-C + CH ₂

I I

S-CH ₃ csn (V) (NaOC ₂ H ₅ )

On

N-C = N

CH, -S-C = N

J (5N HCl) (VI)

C = N

(VII)

The N-cyanedithiocarboximide acid dimethyl ester of formula V, which is used as a starting material in the above process, and the salt of formula VI formed by reaction with malonic nitrile are known compounds (cf. Rec. Trav. Ch. 9/1971, 463; J. Chem. Soc., Chem. Comm. 1974, 350). From the salt of formula VI, the desired compound of formula VII can be obtained by cyclization with a 5N hydrochloric acid solution.

Pesticidally, especially insecticidally active 2,4,6-triamino-5-nitropyrimidines whose amino groups may be optionally substituted are already known from European patent application 0084.758. Compared to these known compounds, the active compounds of the formula (I) prepared according to the invention differ structurally essentially by the presence of the cyano group at the 5-position.

Surprisingly, it has now been found that these compounds of the formula I, as well as their salts, have excellent activity as a pest control agent with good crop plant tolerance and low warm-blood toxicity. Said compounds are particularly suitable for controlling insects and acarina agents that attack plants and animals.

In particular, the compounds of the formula I are suitable for controlling insects of the following orders: Lepidoptera, Coleoptera, Homoptera, Heteroptera, Diptera, Thysanoptera, Orthoptera,

Anoplura, Siphonaptera, Mallophaga, Thysanura, Isoptera, Psocoptera and Hymenoptera, as well as to combat Acarina mite representatives of the family: Ixodidae, Argasidae, Tetra nychidae and Dermanyssidae.

In addition to their action against flies such as housefly (Musea domestica) and mosquito larvae, the active compounds according to the invention can also be used for combating vermin attacking plants in ornamental and crop plants, in particular in cotton crops (e.g. Spodoptera littoralis and Heliothis virescens) as well as in fruit tree and vegetable crops (for example against the lice (Plutella xylostella), Laspeyresia pomonella, Colorado potato beetle (Leptinotarsa decemlineata) and Epilachna varivestis). The compounds of the formula I according to the invention also have good activity against rice pests. The compounds of formula I are furthermore characterized by a pronounced larvicidal activity against insects, in particular against larvae of vermin. When the active compounds according to the invention are taken with food in adult stages of insects, in many cases, in particular in beetles (Coleoptera), such as in the case of Anthonomus grandis, reduced egg laying and / or reduced hatching can be detected.

In addition, the active compounds of the formula I can be used with very good results in combating ectoparasites, such as Lucilia sericata, domestic and productive animals, for example by treating animals, stables and pastures.

Surprisingly, in the treatment of grazing animals with active ingredients according to the invention, for example by cattle baths, watering or spraying, the adhesive effect of the active ingredients surprisingly achieved a long-term toxic effect on ectoparasites, such as harmful diptera species, on the skin and fur of animals. It is thus possible to prevent premature rinsing or flushing of the active substances applied to the surface of livestock from rainwater.

A particular advantage of the active compounds according to the invention is the possibility of oral administration of these compounds to useful animals. In this method of application, the active compounds develop their lasting and long-term insecticidal activity, particularly in the faeces excreted from the digestive tract. This can be prevented by infestation with harmful insects, especially Diptera, before the occurrence of pests in the vicinity of animals such as stables, game and pasture, since the larvae that hatch from the picked eggs are killed immediately. In this particular application, it is of particular importance that the compounds behave physiologically indifferently to warm-blooded owing to their structural properties. This method of deliberately combating insect proliferation is substantially more effective and at the same time more economical than the usual disinfection of stables and the field, carried out over large areas.

Examples illustrating the preparation of the active ingredients and intermediates:

Example 1

Preparation of the starting compound, i.e. 2-chloro-4,6-diamino-5-cyanopyrimidine

A suspension of 50 g of finely powdered 2-chloro-4-amino-5-cyano-6-methylthiopyrimidine in 750 ml of dioxane and 250 ml of water is introduced at 0 ° C. An intense stream of chloroform is then introduced into the suspension with stirring and without cooling. After about 20 minutes a clear solution is obtained. After a further 30 minutes the chlorine introduction was stopped and the mixture was stirred for a further 1/2 hour.

The reaction mixture is evaporated, the residue is suspended in 600 ml of ice-water and then the suspension is filtered. The 2-chloro-4-amino-5-cyano-6-methylsulfonylpyrimidine residue (m.p. 235 DEG C., decomposition) was obtained as a residue on the filter at 46.4 g.

CS 27224-9 B2 hours together with 25 g of 30% aqueous ammonia solution and 1000 ml of acetonitrile at room temperature. After evaporation, the residue is suspended in water and then the product is filtered off. There was thus obtained the title compound of the formula

Melting point greater than 260 ° C.

Preparation of 2-cyclopropylamino-4,6-diamino-5-cyanopyrimidine g 2-chloro-4,6-diamino-5-cyanopyrimidine prepared as described above was suspended in 100 ml of acetonitrile. 14 g of cyclopropylamine are added to this suspension with stirring, and the reaction mixture is then stirred at reflux for a further 12 hours. After cooling, the suspension is poured onto ice / water and the resulting solid is filtered off and washed several times with water. There was thus obtained the title compound of the formula

mp 249-251 ° C (compound δ. 1).

Example 2

Preparation of 2-diethylamino-4-amino-5-cyano-6-isobutyrylaminopyrimidine To a solution of 10.3 g of 2-diethylamino-4,6-diamino-5-cyanopyrimidine in 90 ml of tetrahydrofuran was added 7 g of triethylamine. To this solution was added dropwise at 60 ° C

8.5 g of isobutyric anhydride. The reaction mixture is refluxed for 48 hours, then evaporated and the residue is washed with diethyl ether. The title compound of the formula thus obtained

mp 151-152 ° C (Compound No. 1.3).

Example 3

Preparation of N, N-dimethyl-N '- (2-cyanopropylamino-4-amino-5-cyanopyrimidin-6-yl) formamidine

To a solution of 3.8 g of 2-cyclopropylamino-4,6-diamino-5-cyanopyrimidine in 100 ml of dioxane at 45-50 ° C was added dropwise 3.7 g of dimethylformamide diethyl acetal. The reaction mixture was stirred for 8 hours at 45-50 ° C. After distilling off the solvent and recrystallizing the crude product from ethanol, the title compound is obtained

mp 192-195 ° C (Compound No. 1.4).

The following compounds of formula I are also prepared in an analogous manner

compound no. ^S 1 r ₂ • * 3 ^R 4 temperature (° C 1.5 H -C ₃ H ₇ (s) H -nh ₂ 230-232 1.6 H -CH (CH ₃ ) -C ₂ H ₅ H -nh ₂ 195-197 1.7 -ch ₃ . -CH ₃ H -nh ₂ > 260 1.8 -CýlyCn) -C ₃ H ₇ (n) H -nn ₂ 204-206 1.9 -C ₄ H _g (n) -C ₄ H _g (n) H -nh ₂ 182-185 1.10 -ch ₃ - ^C 2 ^H 5 H -nh ₂ 250-251 1.11 - (ch ₂ ) ₄ - H -nh ₂ > 260 1.12 - (ch ₂ ) ₅ H -nh ₂ 234-236 1.13 H -C _{(CH3) 3} H -nh ₂ 180-183 1.14 -CH-j -C ₄ H _g (n) H -nh ₂ 194-196 1.15 H ~ "\ I H -NH-CO-CH _{(CH3) 2} 215-218

1.16 H

1.17 H

H -NH-CO-C ₂ H ₅ 180-181

H -NK-CO-CH ₃ 203-205

AND

Compound ^R 1 n. r ₂ ^R 3 ^R 4 melting point (° 1.18 - C ₂ E ₅ -c ₂ h ₅ H -NH-CO-C ₂ H ₅ 158-160 1.19 C ₂ H ₅ -o ₂ h ₅ H -NH-CO-C (CH3) ₃ 113-115 1.20 -C ₂ K ₅ -c ₂ h ₅ H -nh-what-ch ₃ 168-171 1.21 C ₂ H ₅ -c ₂ h ₅ H -NK-CO-C ₃ H ₇ 149-150 1.22 H -NH-CO-C _{(CH3) 3} 110-113 1.23 C ₂ H ₅ - ^C 2 ^H 5 H -NH-CO-C ₄ H _g (n) 119-120

1.24 H

1.25 H

1.26 C ₂ H ₅

1.27 H

1.28 -CH ₃

1.29 -Cff ₃

1.30 H

1.31 C ₂ H ₅

1.32 H • 1.33 H

1.34 -C ₂ H ₅

-c ₂ h ₅

-C ₄ H _g (n)

- ^C 2 ^H 5

H -NH-CO-C ₃ H ₇ (n) 175-176

H -NH-CO-C ₄ H _g (n) of from 187 to 188

H -NH-CO-CF ₃ 190-191

H -NH-C0-CF ₃ 268

H -NH-CO-CH _{(CH3) 2} 139-140

H -NH-C0-CH _{(CH3) 2} 146-149

H -NH-C0-CH (C ₂ H _{5) 2} 195-197

H. -NH-CO- (CH ₂ ) ₄ CH ₃ 133-135

H -NH-CO- (CH ₂ ) ₄ CH ₃ 170-173

CK,

AND

H-K = CH-N-CH ₃ 192-195

CH,

AND

H -N = CH-N-CH ₃ 160-165

Compound ^R 1 n. ^R 2 • ^R 3 ^R 4 temperature melting point (° C) 1.38 -CH ₂ -CH = CH ₂ -CH ₃ H · -nh ₂ 199-201 1.39 -CH ₂ -CH = CH ₂ H H ’ -nh ₂ 191-193 1.40 -CH ₂ -CCH H H -NH. > 260 1.41 H -ch ₂ - <] ” -nh ₂ 228-229 1.42 H - < -C «-CH ₃ -NH-CO-CH3 - 260 1.43 -C ₂ H ₅ - ^C 2 ^H 5 -CO-CHg -nh-what-ch ₃ 263-265

The following salts of compounds of formula I are prepared by reacting a compound of formula I with said acid

compound no. ^R 1 ^R 2 e ^R 3 ^R 4 acid temperature melting point (° C) 2.1  O H -NH ₂ HCl 210 (decomposition) 2.2 ^B <] H -NHg F = C-COOH 209-210 2.3 H -NH ₂ (COOH) ₂ 198 (decomposition) 2.4 ^-C 2 ^R 5 - ^ 2 ^R 5 H -NH _? HCl 167-169 2.5 ~ 2 2 ^R 5 “ ^C 2 ^R 5 H -NH ₂ F.C-COOH 175-178

compound no.

* 1 ^S 2 ^S 3 ^R 4 acid melting point (° C)

2.6 -C ₂ H ₅ -C ₂ H ₅ H -NH ₂ (COOH) ₂ 178-188

2-7 <1

H -NH-CO-CH _{(CH3) 2} HC1-140

2.8 H

H -NH-C0-5H (CH _{3) 2} C-COOH 150-153

2.9

2.10 H

H -NH-,

H -NHh ₃ after ₄

208

H ₂ SO ₄

188

2.11 - ^C 2 ^H 5 -C ₂ ^h 5 H -nh ₂ h ₂ Sat ₄ 199-201 2.12 -c ₂ h ₅ -o ₂ h ₅ H -nh ₂ ^K 3 ^ŘO 4 185 2.13 - ^C 2 ^H 5 - ^C 2 ^H 5 H -nk ₂ CH ₃ SO ₃ H 205-207 2.14 H H -nk ₂ CH ₃ SO ₃ H 250 2.15 -c ₂ h ₅ -c ₂ h ₅ H -nh ₂ maleic 150 2.16 H H -nh ₂ maleínová 185 2.17 - ^C 2 ^H 5 -c ₂ h ₅ H -nh ₂ maleic 216-220 2 '. 18 H - < H ' -nh ₂ hno ₃ 163 2.19 -c ₂ h ₅ - ^C 2 ^H 5 H -nh ₂ hno ₃ 179

malonic> 230

H -NH 2 H

As above, the following compounds of formula I can also be prepared:

R,

K - CH ₃ h

H -C ₂ H ₅ H

H-C (H) n) H

-NH-nh ₂

-NH-NH ₂

-nh ₂

-NHH-CH (C ₂ H ₅ ) ₂ H -c ₃ h ₇ (s) -c ₃ h ₇ (s) H -C ₂ phi -C ₂ H ₅ k

-NH

-nh ₂

CO-C.

-NH-CO-C-H 2 5

-nh-co-c ₂ hrs ₅

-CO-C ₃ K ₇

H - <0 -CO-CH _(CH3) - ^C 2 ^H 5 -c ₂ h ₅ -co-c ₂ h ₅ -c ₂ h ₅ -c ₂ h ₅ -CO-C ₃ H ₇ - ^C 2 ^H 5 -c ₂ h ₅ -CO-CH (CH ₃₎

-NH-CO-C ₃ H ₇ (n)

-NE-CO-CH _{(CH3) 2}

-NK-CO-C-H2?

-NH-CO-C ₃ H ₇ (n)

-NH-CO-CH _{(CH3) 2}

- ^C 2 ^H 5

-c ₂ h ₅ ^C 2 ^H 5

-CO-CF ₃ -NH-CO-CF ₃

-co-cf ₃ -nh-co-cf ₃

-CO-CH ₃ -NH-CO-CH (CH ₃ ) ₂

-CO-C ₂ H ₅ -NH-CO-CH (CH ₃ ) ₂

The above compound no.

the following intermediates of formula IV are also prepared by the process:

* 1 ³ 2 melting point (° C)

4.1 H -ch ₃ 270-274 4.2 H -C ₃ H ₇ (i) 171-173 4.3 H 215-218 4-4 H -CK (CH ₃ ) -C ₂ H ₅ ' 143-145 4-5 H -CH (C ₂ H _{5) 2} 151-153 4.6 -ch ₃ -ch ₃ 216-218 4.7 -c ₂ h ₅ ^C 2 ^H 5 131 4.8 -C ₃ K ₇ (n) -C ₃ H ₇ (n) 160-162 4-9 -CjHgín) 120-122 A.10 H tr 270 (decomposition) 4.11 -ck ₃ -C.n- · 15S-160 4:12 -C (CH ₃ ) ₃ 194-196 1.13 - <ce ₂ ) ₄ - 193-2C0 4.14 - (CH ₂ ) ₅ - - .204 - 206 4.15 -ch ₃ -C ₄ H _g (n) .158 - 160

The following intermediates of formula IV can also be prepared as described above

The biological effects of the compounds of formula I are described in U.S. Pat. No. 271,471.

Claims (8)

SUBJECT OF THE INVENTION A process for the preparation of novel substituted 2,4-diamino-5-cyanopyrimidines of the general formula I (I) in which R ^ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms or an alkynyl group having 2 to 6 carbon atoms, R ₂ is hydrogen, alkyl having 1 to 10 carbon atoms or cycloalkyl having 3 to 6 carbon atoms or R 1 and R ₂ together represent - (CH 3) 2 -, - (CH 3) 2 - or - (CH 2) 2 -, R 1 represents a hydrogen atom or a group -CO-R 6, R ^ is -NIL, -NH-CO-R ^ or -N = CH-N (Rg) (Rg), R @ 1 is C1 -C12 alkyl or trifluoromethyl a R _g and Sq are independently alkyl having 1 to 6 carbon atoms, and their salts, characterized in that the compound of formula III (III) with an amine of formula IV HN (IV) wherein and R ₂ are as defined above, whereupon a compound of formula I wherein R 1 is hydrogen and R 1 is -NH ₂ , i.e. a compound of formula Ia (Ia) in which R and EG have the above meanings, or converted with a compound introducing the radical -CO-R and / or = CH-N (R _g) (R g) to give a compound of formula I wherein R is -CO-R ^ and / or R is a group -NH-CO-R b or -N = CH-N _(Rg) (Rg), wherein R, R and R are as defined above and the compound of formula I is optionally converted into a salt . 2. A process according to claim 1, wherein the corresponding starting materials and reaction conditions are used to form compounds of formula (1) wherein R @ 1 is hydrogen or C1 -C4 alkyl, R @ 8 is C1 -C4 alkyl. up to 4 carbon atoms or a (C 3 -C 6) cycloalkyl group, or R 6 and R 6 together represent - (CH 6) 4 - or - (CH 6) 4 -, R 6 represents a hydrogen atom, R 6 represents an -NH 8 group or - NH-CO-R1 and R1 are C1-C4alkyl or trifluoromethyl, or salts thereof. 3. A process according to claim 2, wherein the corresponding starting materials and reaction conditions are used to form compounds of formula (I) wherein R1 is hydrogen, methyl or ethyl, R8 is alkyl and 1 to 4 atoms. R ^ is hydrogen, R ^ is -NHg or -RH-CO-R ^ and R ^ is an alkyl group of 1 to 3 carbon atoms, or salts thereof. 4. A process according to claim 3, wherein the corresponding starting materials and reaction conditions are used to form compounds of formula (I) wherein R6 is hydrogen, methyl or ethyl, R8 is cyclopropyl, R6 is hydrogen and R R are -NHg or -NH-CO-CgH ^ as well as salts thereof. 5. A process according to claim 4, wherein the corresponding starting materials and reaction conditions are used to form a compound of formula NHg 6. A process according to claim 4, wherein the corresponding starting materials and reaction conditions are used to form a compound of formula NHg Y7 ’en 272249 Β2 7. A process according to claim 4, wherein the corresponding starting materials and reaction conditions are used to form a compound of the formula 8. A process according to claim 4, wherein the corresponding starting materials and reaction conditions are used to form a compound of formula