EP0425584A1 - Prostaglandin-derivatives having antithrombotic activity - Google Patents

Abstract

The invention relates to the compounds of formula (I) in which n = 2, 3; m = 4, 5, 6, 7; X = NHR, CH2NHR, NHNH2; R = H, a linear or branched (C1-C4) alkyl, a linear or branched (C1-C4) acyl; Y = CH2NH2, COOH, CONH2 (excluding compounds in which n = 2, m = 5, X = NHR with R = H, a (C1-C4) linear or branched alkyl, a (C1-C4) acyl linear or branched; Y = COOH, CONH2) comprising all the optical and / or geometric isomers, alone or mixed, as well as their salts, inhibiting the aggregation of platelets in the blood, and which can be prepared for use as antithrombotic agents, anti-platelets.

Description

PROSTAGLANDIN-DERIVATIVES HAVING ANTITHROMBOTIC ACTIVITY

The instant invention refers to the activity and use of compounds having a prostaglandin-like structure as well as pha maceutical compositions thereof, having platelet antiaggregati antithrombotic activity.

It is known that substances such as ADP, collagen, throm bin , arachidonic acid , favour platelet aggregating phenomena -^**-⁰ causing the formation of thrombi which are mainly responsible for ischemic,cardio- and cerebro-vascular disorders, theroscle rotic peripheral arterial disorders and venous thrombosis. Thu substances which are capable of antagonizing their effects are of considerable therapeutic interest. ¹⁵ In the course of studies carried out by the Applicants on prostaglandin-like compounds, possessing antiulcer activity, described in IT 1,190,400 filed on October 4,1985 and in IT 1,205,183 filed on June 25,1987 (corresponding to the PCT patent application No. IT88/00010 of February 10,1988), both

20 owned by the Applicants, it has been discovered that some of the compounds, disclosed therein and corresponding to formula( of the instant application, possess antiplatelet, antithrombot activity.

The compounds of formula (I) 5

0 wherein: n = 2,3; m = 4,5,6,7; X = NHR, CH NHR, NHNH , wherein R = H, a linear or branched (C -C )alkyl, a linear or branched (^C.,-C₄)- acyl; Y = CH NH , COOH, CONH (with the exclusion of the com¬ pounds wherein n = 2, m = 5, X = NHR with R = H, a linear or branched (C -C )alkyl, a linear or branched (C -C )acyl; Y = COOH, CONH ) possess 3 asymmetric carbon atoms identified by an asterisc, wherefore 8 stereoisomers are possible.

Therefore, when not otherwise specified, the above formu la (I) includes all possible stereoisomers, all possible com¬ binations of two or more such stereoisomers, of enanthiomers o mixtures of enanthiomers in any proportion.

The four pairs of possible enanthiomers indicated by the code Nos.IBI-P-(I)A, IBI-P-(I)B, IBI-P-(I)C, IBI-P-(I)D, are represented as follows:

(cis-cis) (cis-cis)

(trans-trans ) (trans-trans

(trans-cis) (trans-cis)

(cis-trans)

wherein, considering the planar or almost planar ring, lying in the horizontal plane of the sheet, as is customary in che ical literature, the broken lines indicate that a particular εubstituent lies below the molecular plane, while the full lines in the form of a wedge indicate that a particular sub- stituent lies above the molecular plane. The prefices cis an trans are used to indicate the relative position of the sub- stituents with respect to one another.

More particularly,the instant invention relates to pros compounds of the above cited formula (I), useful for prepari pharmaceutical compositions having antiplatelet, antithrombo -

ic activity.

It is reiterated that the compounds of formula. (I) are the subject matter of IT 1,190,400 filed on October 4,1985 an of IT 1,205,183 filed on June 25,1987, of which Applicants are the proprietors, wherein their activity as antiulcer agen and their use for preparing pharmaceutical compositions are described, and, therefore, they are not being claimed, per se herein, whereas Applicants wish to protect their use as inhi¬ bitors of platelet aggregation and antithrombotic agents. The compounds of formula (I) wherein n = 2, m = 5, X =

NHR with R = H, a linear or branched (C -C )alkyl, a linear o branched (C^C^acyl, Y = COOH, CONH , fall within the scope of IT 1,060,366 filed on August 7,1974, owned by Applicants, which discloses their activity as inhibitors of platelet agg gation and hence such compounds are excluded from the present invention.

The present invention includes also the pharmaceuticall acceptable cationic salts of the compounds of formula (I) whe Y = COOH and, in general, the pharmaceutically acceptable anionic salts.

As used herein, the expression "pharmaceutically accept able cationic salts" refers to the alkali and alkaline-earth metal salts such as, e.g. sodium; potassium, calcium, magne.- sium, or salts of aluminum, ammonium, zinc and of organic amines, including the amino acids such as, e.g. lysine,argi- nine, phenylalaline and proline, triethanol amine, inner sal and salts of basic resins.

As used herein, the expression "pharmaceutically accept able anionic salts" refers to salts obtained by the addition of hydrochloric, hydrobromic, nitric, phosphoric, sulfuric, benzenesulfonic, benzoic, citric, laurylsulfonic, fumaric,oxali maleic, ethanesulfonic, tartaric, ascorbic, p-toluenesulfonic, salicylic and succinic acid.

With polybasic acids, the salt may include more than one mole of base per mole of acid. However, the salts obtained from one mole of acid per mole of the inventive compound are preferr The present invention, lastly, refers to pharmaceutical c positions containing a compound of formula (I) or a pharmaceuti cally acceptable anionic or cationic salt thereof. The preparation of some of the compounds of formula (I) h already been described in IT 1,190,400 of October 4,1985 and IT 1,205,183 filed on June 25,1987.

For example, in said patents is described the preparation of the compounds of formula (I) wherein: n = 2, m = 5, X = CH₂NH₂, Y = COOH (IBI-P-01058) n = 2, m = 5, X = NHNH₂, Y = COOH (IBI-P-01062) n = 2, m = 5, X = NH₂, Y = C^NH (IBI-P-01068) n = 3, m = 5, X = NH , Y = COOH ^" (IBI-P-05006) n = 3, m = 5, X = CH NH , Y = COOH (IBI-P-05011) n = 3, m = 5, X = NH , Y = CH NH (IBI-P-05012) n = 2, m = 6, X = NH , Y = COOH (IBI-P-12004)

Here below is given, for illustrative purposes only, the preparation of the compounds of formula (I) wherein: n = 2, m = 4, X = NH , Y = COOH (IBI-P-12003) n = 2, m = 7, X = NH , Y = COOH (IBI-P-12005) n = 3, m ^**= 5, X = NH , Y = COOH (IBI-P-05006) which may be prepared according to the reaction scheme I : SCHEME I

wherein Y¹ - CH NH , CONH , COOR' and R' = a linear or branche H(C₁-C₄)alkyl.

The cycloalkenone of formula (II), when n = 2, may be pr pared as described in IT patent application 19043 A/84 of Janu ry 5,1984 (continuation-in-part U.S.S.N. 117669 of November 5, 1987 of U.S. application S.N. 744406 of June 13,1985) owned by Applicants.

It has now been found that when n = 3, Y¹ = C00CH , the

3 cycloalkenone of formula (II ) may be prepared according to the ollowing reaction scheme II : SCHEME II

(VI I I ) ( IX )

( II ) with n = 3;Y = COOαy Hal = Cl,Br,I. The monochloride of 8-carbomethoxy-oc tanoic, acid (X ) (pre¬ pared a s disclosed in IT patent application 19043 A/84 ) is con¬ densed as a Grignard compound of formula ( IX )

wherein Hal = Cl , Br , I ; p = 2 , 3 in inert polar solvents such as, e.g. tetrahydrofuran, ethyl ether, butyl ether, dioxane, dimethylformamide. The acetal of the 1,5-dicarbonyl compound(XI) .prepared by gnard condensation, can be cyclized by acid catalyzed,intramole lar crotonic condensation, in a suitable solvent, yielding the desired compound of formula (II).

The compounds of formula (IX) may be prepared according t methods known from the literature, for example by monohalogenati of the 1,4-butanediol (V) performed as described by Suk-Ku-Kang i Synthesis,1161 (1985) ,oxydation of the aldehyde (VII) of the 6^-halobutanol (VI) with a catalytic process employing sodium h chlorite as the oxydizing agent and the free radical 2,2,6,6-tet methyl-piperidinyl-1-oxyl as the catalyst, as described by

P.L.Anelli.C.Biffi, F.Montanari in J.Org.Che .5_2,2559 (1987) and the subsequent protection of the carbonyl group of the compounds of formula (VII), with ethylene glycol or with 1,3-propanediol, and the subsequent transformation into a Grignard reagent, viz. the compound of formula (IX).

As described in IT 1,205,183 filed on June 25,1987, the cy cloalkenone of formula (II) may be transformed into the cycloal- kanone of formula (III) wherein m = 4,5,6 and 7, using a Grignar reagent such as, e.g. CH (CH t-__) Til MgHal (Hal= C1,B,I) in the prese of copper salts such as,e.g. CuCl, Cu(OAc) ,CuCN, CuI.CuCl . Pol - 8 -

and inert solvents are generally used such as, e.g. tetrahydro furan, dimethyl-formamide, ethyl ether, butyl ether.

The compounds of formula (IV) can be prepared from the c responding cycloalkanones (III) by using per se known reaction such as e.g. reductive aminations with ammonia, hydrogen and m catalysts, in alcoholic solvents, at a temperature of from 30° 100°C and at a pressure of from 1 to 20 atms according to reac scheme I, or according to methods known from the technical lit ture, according to scheme III: SCHEME III

through reduction of the cycloalkanones of formula (III) to th alcohols (XII) with hydrides selected among lithium aluminum hydride, sodium boronhydride, lithium tri-sec-butyl boronhydri lithium dicyclohexyl-tert-butyl boronhydride, lithium di-sec- butyl hexyl boronhydride, lithium diisobutyl-tert-butyl boron dride; preparation of the mesilate (XIII) .substitution of the mesilate with sodium azide to yield the compounds of for ula( and subsequent reduction with metal catalysts and hydrogen. A disclosed in IT 1,205,183 filed on June 25,1987, the compound formula (IV) can subsequently be converted into the compounds formula (I), e.g. wherein Y = COOH and X = NH , in aqueous, o aqueous alcoholic, or alcoholic solutions, of bases such as.e. N NaaO0HH,,KK0H, K CO , which are capable of hydrolizing the carbalc group.

The compounds of formula (I) prepared according to the p cesses of the instant invention, when not otherwise specified, generally consist of mixtures of the stereoisomers in ratios d pending on the route of synthesis, on the reagents used and th experimental conditions.

The desired enanthiomer pairs can be prepared by separat the stereoisomeric mixtures by methods known to the man skille in the art.

It is, for example, possible to isolate chromatograp ica a pair of enanthiomers from a mixture containing all the stere isomers of the compounds of formula (I) or of formula (IV); as stationary phase one can use e.g. acid alumina, neutral alumin basic alumina, cellulose, charcoal, silica, Amberlite XAD 2 (Fluka), Amberlite IRC 50 (Fluka); and as eluent it is possibl to use a solvent or a solvent mixture selected among e.g.ethan methanol, ethyl acetate, acetone, ethyl ether,methylene chlori chloroform, hexane, petrol ether, per se or in admixture with bases such as e.g. diethylamine, isopropylamine, triethylamine and ammonium hydroxide. The thus separated enanthiomer pairs o the compounds of formula (IV) yield the corresponding enanthio pairs of formula (I), by saponification with suitable bases, i alcoholic or hydroalcoholic solvents.

It is possible to prepare an enthiometer pair of formula( by fractional crystallization of salts of stereoisomer mixture of the compounds of formula (I) or of formula (IV), prepared b addition of inorganic or organic acids selected e.g. among the following acids: hydrochloric, hydrobromic, nitric, phosphoric, sul uric, benzenesulfonic, p-toluenesulfonic, me hanesul onic, acetic, trifluoroacetic,oxalic, maleic, benzoic, in solvents o solvent mixtures selected among e.g. isopropanol, ethanol, met anol, ethyl ether, diisopropyl ether, dioxane, tetrahydrofuran, chloroform, methylene chloride, benzene, toluene, at a tempera ture of from -20° and +40°C and subsequent reaction with bases to yield the desired enanthiomer pairs in their free form. t is furthermore possible to prepare each enanthiomer p of the compounds of formula (I) by chromatographically separat the mixture of the stereoisomer alcohols (XII) prepared by red tion with stereoselective reducing agents as described by CH.Brown, S.Kirishnamurthy in J.Am.Chem.Soc. 7159 (1972), or reduction with reducing agents having a low steric demand

(Scheme III) of the compounds of formula (III) and subsequent conversion into the corresponding mesilate, substitution with sodium azide and reduction with hydrogen and metal catalysts. The instant invention shall now be further described by the following examples illustrating the preparation of the compoun of formula (I), of the intermediates of formula (I) as well as of the enanthiomer pairs.

Example 1

2-(6'-carbomethoxy-n-hexyl)-2-cyclohexene-l-one (a derivative of formula(II) wherein n = 3 and Y¹ = CO.OCH . a) A suspension of magnesium (19.6 g) in tetrahydrofuran (220 is added with a solution of 2-(4-bromobutyl)-l ,3-dioxolane

(prepared according to reaction scheme II) in tetrahydrofur (1600 ml) keeping the temperature at 20-25°C, at the end of which the reaction mixture is kept under stirring for furth 60 min. The reaction mixture is cooled to -45°C and added w the monochloride of 8-carbomethoxy-octanoic acid (prepared cording to the method disclosed in IT patent application 19 A/84 of January 5,1984), keeping the temperature between -4 and -45°C. The reaction mixture is stirred for 5 hrs at -15° at the end of which a 15% solution of sodium chloride(120 ml and ethyl ether (120 ml) is added thereto.

The organic phase is separated, washed to neutrality wit a sodium chloride aqueous solution; it is then anhydrated o sodium sulfate and the solvent is evaporated under reduced pressure yielding 125 g of crude 2-(ll-carbomethoxy)4-oxo-n- undecyl)-l,3-dioxolane which is used without any further pu¬ rification. b) A solution of the compound (125 g) prepared according to the preceding step (a) dissolved in tetrahydrofuran (1000 ml) is reacted 16 hrs at room temperature with 6N hydrochloric acid (300 ml) .

At the end, the reaction mixture is extracted with methylene chloride (2 x 300 ml), and the organic phase is washed to neutrality with a 10% brine solution.

It is then anhydrated over Na ^"SO and the solvent is distil off under reduced pressure. The thus obtained crude materia contains, as the main by-product,2-(6'-carboxy-n-hexylj-cyclo hexene-2-one which is converted into the title compound by reaction with methanol and p-toluenesul onic acid. The thus prepared compound is distilled at 0.3 mmHg whereby the frac- tion having a b.p. of 140°-142°C is collected; 60 g of the title compound is obtained. Analytical Data

B.p. : 140°-142°C at 0.3 mmHg

-1 -1 I.R. (^*\) max) = 1740 cm , 1675 cm NMR ( 8 ) = 6.75 (m,lH); 3.7(s,3K); 2.2 (m,8H); 1.5 (m,10H)

Calculated : C = 70.56% H = 9.30%

Found : C = 70.47% H = 9.21%

Example 2

2-(6'-carbomethoxy-n-hexyl)-3-n-hexyl-cyclohexanone (a derivati of formula (HI) wherein n = 3, Y^{1 ■****}- C00CH ) .

This derivative is prepared according to the process disclosed IT Pat.Appln. 19043 A/84 filed on January 5,1984, by reacting 2-(6'-carbomethoxy-hexyl)-2-cyclohexene-l-one) (41 g) with brom hexane (52 g) and Cul (3.3 g); 48.3 g of the title compound is obtained.

Analytical Data

-1 -1 I.R. ( - max) : 1740 cm , 1710 cm

NMR ( S ) = 3.7 (_s , 3H) ; 3.6-1.1 (m, 30H) ; 0.95 ( s , 3H) Example 3 2- ( 6 ' -carbome thoxy-hexyl )-3-pentyl-cyclopentanone

This derivative is prepared, as described in example 2, by reac ing 2-(6 '-carbomethoxy-hexyD-2-cyclopentene-l-one (67 g) with Mg (14.4 g), bromopentane (96.6 g) and Cul (5.7 g) yielding 73 g of the title compound. I.R. (\> max) : 1740 cm^" Example 4

2-(6'-carboxyhexyl)-3-pentyl-cyclopentanone The compound of example 3 is dissolved in methanol (300 ml) an treated with a solution of NaOH (24 g) in water (300 ml).

The reaction mixture is refluxed under stirring to compl tion of the reaction. Then it is cooled, acidified to pH 2, ex tracted with methylene chloride (250 ml) and washed with water to neutrality. The reaction mixture is anhydrated and the solv is distilled off; 68 g of the title compound is obtained. Example 5 2-(6 '-carboxyhexyl )-3-pentyl-cyclopentyla ine (a derivative formula (I) wherein n = 2, m = 4, X = NH , Y = C00H(IBI-P-1200 The compound of example 4(68 g) is reacted with methanol (1000 ammonia (200 g), PtO (3 g), at a temperature of from 40 - 60° in an autoclave, and left for 3 days under hydrogen pressure, yielding 42 g of a solid white compound. Analytical data: ffl.p. = 166°-168°C

-1 -1

I.R. ( Λ) max) : 3300 cm , 1560 cm

NMR ( 5 ) = 4.6 (s, 3H); 2.8 (m, 1H) ; 1.2(m, 26H) ; 0.9(t,3H) Titer (as base) = 96%

Calculated: C = 72.08% H = 11.66% N = 4.95%

Found : C = 71.92% H = 11.72% N = 4.98%

Example 6

2-(6 '-carbomethoxy-hexyl)-3-octyl-cyclopentanone

This derivative is prepared in an analogous manner to that de¬ scribed in example 3, using as the starting material 2-(6'-car bomethoxy-hexyl)-2-cyclopentene-l-one (67 g); yield : 78 g of the title compound.

I.R. ( \) max) : 1740 cm^" Example 7

2-(6'-carboxyhexyl)-3-octyl-cyclopentylamine (a derivative of formula (I) wherein n= 2,m = 7, X = NH , Y = COOH (IBI-P-12005 This derivative is prepared in analogous manner to that descri in example 5, using as the starting material 2-(6'-car_boxyhexy 3-octyl-cyclopentanone (75 g) . Finally, 34 g of a solid white material is yielded. Analytical Data m.p. = 152° - 154°C

I.R. (Λ) max) : 3300 cm^" , 1560 cm^"

NMR ( S ) = 4.6 (s,3H); 2.8 (m,lH); 1.2 (m,32H); 0.9 (t,3H) Titer (as base) = 98% Example 8 2-⁽6'-carbomethoxy-hexyl⁾-3-n-hexyl-cyclohexylamine

A suspension of 2-(6'-carboxyhexyl)-3-n-hexyl-cyclohexylamine (200 g) (IBI-P-05006, a compound disclosed in IT 1,205,183 fil on June 25,1987), in methanol (100 ml), is added with p-toluen sulfonic acid. ^Tne reaction mixture is refluxed three hours, cooled to room temperature, then the solvent is concentrated under reduced pressure and the reaction mixture is added with a IN NaOH aque ous solution (1000 ml) and extracted_with ethyl ether (2x300 m The organic phase is washed to neutrality with a 20% brine reduced pressure, yielding 203 g of a colorless oil.

Analytical Data

-1 -1 I.R. (-ύ max) : 1745 cm , 1670 cm

Calculated : C = 73.85% H = 12.00% N = 4.31% Found : C = 73.90% H = 12.11% N = 4.27%

Example 9

R,S-cis-2-(6'-carbomethoxy-hexyl)-cis-3-n-hexyl-cyclohexylamin

A solution of 2-(6 '-carboxymethoxy-hexyl)-3-n-hexyl-cyclohexyl mine(100 g)in methanol(500 g)is added with p-toluenesulfonic a (61.4 g) and stirred for 15 min at room temperature, whereupon the solvent is distilled off under reduced pressure: a white solid material is obtained.

The thus obtained solid material is suspended in ethyl ether (500 ml) and stirred for 60 min at room temperature. The reaction mixture is filtered on a Btlchner funnel and the solid material is dessicated, yielding 104 g R,S-cis-2 carbomethoxy-hexyl)-cis-3-n-hexyl-cyclohexylamine p-toluenesul fonate.

The thus obtained solid is treated with water (250 ml) a with a IN NaOH aqueous solution (250 ml),stirred 10 min and ex tracted with ethyl ether (500 ml): the organic phase is then washed to neutrality with a 20% brine ,anhydrated over Na SO an the solvent is distilled off under reduced pressure. Yield: 43.5 g of a colorless oil. Elemental Data

-1 -1 I.R. (\) max) : 1745 cm , 1675 cm

NMR ( S ): 3.6 (s,3H); 2.69 (m,lH); 2.27 (t, 2H) ; 1.6-0.9(broad,

30H); 0.85 (t, 3H) Calculated: C = 73.85% H = 12.00% N = 4.31% Found : C = 73.79% H = 11.95% N = 4.37% Example 10

R,S-cis-2-(6-carboxyhexyl)-cis-3-n-hexyl-cyclohexylamine (IBI-P-05006A)

NH_£

(racemate)

The compound (40 g) of example 9 is dissolved in methanol(400 and added with a potassium carbonate (34.2g) water (60 ml) so tion. The reaction mixture is refluxed three hours; it is the cooled and the solvent is distilled off under reduced pressur The reaction mixture is then added with water (250 ml) .acidif to pH 5.6-5.8 with a 3N HC1 solution, filtered off, washed wi water, acetone, and dessicated under reduced pressure yieldin 36 g of a white solid compound. Analytical data m.p. = 208⁶-210°C Titer (as base) = 98.67%

Calculated : C = 73.31% H = 11.90% N = 4.50% Found : C = 73.41% H = 12.00% N ■= 4.61% Example 11

R,S-cis-2-(6'-carbomethoxy-hexyl)-cis-3-n-hexyl-cyclohexanol a) 2-(6'-carboxyhexyl)--3-n-hexyl-cyclohexanol (125 g) is re¬ acted with a IN lithium-tri-sec-butylboronhydride solution THF (800 ml) according to the method described by H.C.Brow et al in J.Am.Chem.Soc. 7159 (1972) .yielding 130 g of an o material essentially consisting of a mixture of R,S-cis-2-( carboxyhexyl)-cis-3-n-hexyl-cyclohexanol and of R,S-cis-2- (6'-carboxyhexyl)-trans-3-n-hexyl-cyclohexanol. Analytical data: I.R. ( max) : 3400 cm^"1, 1710 cm^"1 The thus obtained compound is dissolved in methanol (750 m and added with p-toluenesulfonic acid (12.5 g). The reaction mixture is refluxed 90 min, cooled and the me anol is concentrated under reduced pressure; the reaction mixture is then added with water (600 ml) and ethyl ether (400 ml). The organic phase is washed with a 20% brine, anhydrated o and the solvent is distilled off under reduced p fres yielding a yellow oil (124.3 g) consisting of a mixture of R,S-cis-2-(6'-carbomethoxyhexyl)-cis-3-n-hexyl-cyclohexano and of R,S-cis-2-(6'-carbomethoxyhexyl)-trans-3-n-hexyl-cy hexanol.

Chro atographing the stereoisomer mixture by silica T.L.C. using as the eluent a 7:3 hexane:ethyl acetate mixture, th cis-cis enanthiomer pair gives a R.f. = 0.50 whereas the c trans enanthiomer pair gives a R.f. = 0.59. The stereoisomer mixture is chromatographed on silica gel column using as the eluent a 7:3 hexane:ethyl acetate mixt recovering the enanthiomer pair having a R.f. = 0.50. Yield: 70 g of the title compound.

Analytical Data

-1 -1 I.R. ( -0 max): 3450 cm , 1742 cm

NMR (^*f ): 3.70 (m, 1H) ; 3.68 (s,3H), 2.3 (t,2H); 1.8-1(bro

29H); 0.87 (t,3H). Calculated: C = 73.61% H = 11.66%

Found : C = 73.55% H = 11.71%

Example 12

R , S- 1 rans-2- ( 6 ' -carbome thoxyhexyl ) -cis- 3- n-hexyl-cyc lohexy azide A solution of R , S-cis-2- ( 6 ' -carbomethoxyhexyl ) -cis-3-hexyl cyclohexanol (70 g) in methylene chloride (350 ml) is added with triethyla ine (51.7 ml) and methanesulfonyl chloride (34.3 g) is added dropwise.at a temperature of from 0° to 5° the reaction mixture is reacted 30 min at the same temperatu and at the end it is poured into water (600 ml). The various phases are separated; the organic phase is washed to neutral with a 10% brine, anhydrated over Na SO and the solvent is distilled off under reduced pressure, whereby 93.9 g of a cl oil is obtained. (I.R. ( \⁾ max): 1740 cm —1,1340 cm—1,1170 cm That residue is taken up with water (850 ml), added with NaN

(37.4 g), hexadecyltributylphosphonium bromide (12.22 g) and stirred 4 hours at 65°C.

At the end, the reaction mixture is cooled and extracted wit ethyl ether (500 ml). The organic phase is then washed with 20% brine, anhydrated over Na SO , and the solvent is distil off under reduced pressure, yielding 96 g of an orange oil.

The material is purified by silica gel chromatography, eluti with 95:5 hexane:ethyl acetate.

Yield: 42 g of the title compound. Analytical Data

-1 -1 I.R. (λ) mx) : 2100 cm , 1745 cm

Example 13

R, S-trans-2-(6'-carbomethoxyhexyl)-cis-3-n-hexyl-cyclohexyl- amine A solution of R,S-trans-2(6'-carbomethoxyhexyl)-cis-3-n-hexy cyclohexylazide (42 g) in methanol (400 ml) ethyl ether (200 is added with 5% Pd/C (4 g) .

The reaction mixture is then shaken 5 hours under hydrogen a phere, then the catalyst is filtered off and the solvent is distilled off under reduced pressure; the residue is chromat graphed on silica gel using an 80:20:0.5 hexane:acetone:ammon mixture as the eluent.

Yield: 9.6 g of an oily material consisting essentially of th title compound. Analytical Data

-1 -1 I.R. (\) max): 1745 cm , 1675 cm

NMR (<5 ) : 3.65 (s,3H); 2.65 (m,lH); 2.25 (t,2H); 1.7-l(broad,

30H); 0.82 (t, 3H) Example 14 R,S-trans-2-(6 '-carboxyhexyl)-cis-3-n-hexyl-cyclohexylamine

9.6 g of R,S-trans-2-(6'-carbomethoxyhexyl)-cis-3-n-hexyl-cycl hexylamine is treated in the same way as described in example Yield: 5.2 g of the title compound as a white solid. Analytical Data m.p. = 154°-156°C.

_1 I.R. ( i max) : 1580 cm Calculated: C = 73.31% H = 11.90% N = 4.5%

Found : C = 73.28% H = 11.97% N = 4.45%

Titer (as base) 99.3%

The activity of the inventive compounds as platelet aggregatio inhibitors and as antithrombotic agents has been investigated in vitro determining the percent inhibition of the platelet ag gregation induced by ADP, collagen, arachidonic acid and throm bin using platelet-rich plasma (hereinafter referred to as PRP) of mammals according to G.V.R.Born: Nature 194, 927-929 (1962) and G.V.R.Born and M.J.Cross:Physiol .168, 178-195(1963) 1) Inhibition of platelet aggregation by added ADP with rat PR

3 The tests are conducted with rat PRP (500,000 platelets/mm adding a compound of formula (I) or a pharmacologically ac¬ ceptable salt thereof so that its plasma concentration be 10 Mincubating 9 min at room temperature; whereupon as ag gating agent ADP (3 ,uM) is added^* and the percent inhibitio of the platelet aggregation is measured using the turbidim ric method of Born and Cross (Table 1)-.

2) Inhibition of platelet aggregation by added collagen with rat PRP

The test is carried out as described sub 1) (inhibition of platelet aggregation by added ADP), using collagen (3 mcg/ as the aggregating agent (Table 1).

3) Inhibition of platalet aggregation by added arachidonic ac with rat PRP

The test is carried out as described sub 1) (inhibition of platelet aggregation by added ADP), using arachidonic acid (200,uM) as the aggregating agent (Table 1).

4) Inhibition of the platalet aggregation by added thrombin with rat PRP

The test is carried out as described sub 1) (inhibition of platelet aggregation by added ADP), using thrombin (0.1 U/ as the aggregating agent. The transmittance measurements h been effected with a Chromo-Log or Elvi 840 aggregometer.

C O M P O U N D Percentage of inhibition of platelet aggr gation with rat PRP, with added:

ADP Collagen Arachidonic Thrombi acid

2-(6'-carboxyhexyl)-3-hexyl-aminomethyl- cyclopentane (IBI-0-01058) 18 26 96 95

12.-(6'-carboxyhexyl)/-3-hexyl-cyclopent- yl hydrazine chloride (IBI-P-01062) 35,6 82 62 47

2-(7'-aminoheptyl)-2-hexyl-cyclopenty1- amine (IBI-P-01068) 100 100 100 100

2-(6'-carboxyhexyl)-3-hexyl-cyclohexyl- a ine (IBI-P-05006) 10 100 100 67,

2-(6'-carboxyhexy1)-3-hexyl-aminometh- yl-cyclohexane (IBI-P-O5011) 11,6 69,7 100 100

2-(7'-aminoheptyl)-3-hexyl-cyclohexyl- amine (IBI-P-05012) 100 98

2-(6'-carboxyhexyl)-3-pentyl-cyclopent- ylamine (IBI-P-12003) 10 73 66 10

2-(6'-carboxyhexyl)-3-heptylcyclopentyl- amine (IBI-P-12004) 24 93 100 96,

2-(6'-carboxyhexyl)-3-octyl-cyclopentyl- a ine (IBI-P-12005) 13,5 70 100 100

R,S-cis-2-(6'-carboxyhexyl)-cis-3-n-hex- yl-cyclohexylamine (IBI-P-05006 A) <10 100 100 15

R,S-trans-2-(6'-carboxyhexyl)-cis-3-n- hexyl-cyclohexylamine (IBI-P-05006 C) <10 100 100 45, The compounds of formula (I) wherein n = 2, m = 5, X = NHR with R = H, a linear^"o^'r branched (C -C )alkyl, a linear or branched (C -C )acyl; Y =COOH ,CONH disclosed in IT 1,060,366 filed on August 7,1974 of which Applicants are the owner, have shown a very low inhibition of platelet function, antithrombot activity.

Table 2 illustrates the percent inhibition of platelet functio with rat PRP, determined under the same conditions and at the

_3 same compound concentrations (10 M) as well as at the same con centration of the aggregation favoring agent as used in the above described tests of platelet function, for example for the compounds according to the above referred formula (I) wherein : n = 2, m = 5, X = NH , Y = COOH (IBI-P-01009) n = 2, m = 5, X = NHC0CH , Y = COOH (IBI-P-01012) n = 2, m = 5, X = NHCH , Y = COOH (IBI-P-01013) n = 2, m = 5, X = NHCH(CH ) , Y = COOH (IBI-P-01015 n = 2, m = 5, X = NH , Y = CONH (IBI-P-013036) .

31

T A B L E

( COMPARISON )

COMPOUNDS OF IT 1,060,366 Percentage of inhibition of the platelet ag¬ EXCLUDED FROM THE INSTANT gregation with rat PRP,added with

It therefore can be seen that the compounds subject of the insta invention show an antiplatelet, antithrombotic activity which is surprisingly higher(more than 10 times)over that of the compounds disclosed in IT 1,060,366 filed on August 7,1984.

The compounds of the instant invention are preferably adminis¬ tered as pharmaceutical compositions in admixture with one or more pharmacologically acceptable diluents and/or carriers. Within the scope of the instant invention the expression "pharmacologically acceptable diluents and/or carriers" refers to substances such as e.g. starch and derivatives thereof (e. g. maize starch, STA RX 150Cr-, which is a registered tradenam of Colacon Ltd., Orpington, Kent, rice starch,carboxymethyl starch); cellulose and derivatives thereof (e.g. Avicer-% registered tradename of FMC Corporation, Philadelphia, U.S.A., and methyl cellulose, ethyl cellulose, hydroxypropylmethy1 ce lulose); silicates and silica oxides (e.g. talc,hydrated calci silicate,Mg and Al silicates, Aerosil (S), registered tradename

Wacker-Chemie GmbH, Munich, Fed.Repub.of Germany, Syloiα-% registered tradename of W.R.Grace & Co., New York, U.S.A.); ionic solid surfactants (e.g.sodium laurylsulfate) and non-io surfactants (e.g. fatty acid esters of saccharose); acrylic d rivatives and polymers thereof; alkali and alkaline-earth met sulfates, carbonates and phosphates; polyvinyl pyrrolidone an derivatives thereof. Preferably, the inventive compounds are administered orally (e.g. as tablets, capsules, granules, syr ups) or parenterally (i.v. or i.m.). Although the dosages may vary according to the symptoms, sex, body weight and conditio of the patient as well as to the frequency of the route of ad ministration, the inventive compounds can be administered ora ly to an adult at a daily dose of from 1 to 2000 mg, preferab of from 10 to 1000 mg, per single dose, or in doses subdivide over a period of 24 hours.

Claims

C L-A I S 1. The use of a compound of formula (I)

(I) including all possible opticical and/or geometrical isomers wherein: ' n = 2,3; m = 4,5,6,7; X = NHR, CH_≥NHR, NHNH , wherein R = H, a linear or branched (C -C )alkyl, a linear or branched (C -C acyl, Y = CH NH , COOH, CONH , with the exclusion of the com¬ pounds according to formula (I) wherein n = 2, m = 5, X = NHR with R = H, a linear or branched (C -C )alkyl, a linear or branched (C -C )acyl, Y = COOH, CONH ; or a pharmaceutically acceptable salt thereof for preparing pharmaceutical composi¬ tions having antiplatelet, antithrombotic activity, in human and veterinary medicine.

2. A process for preparing R,S-cis-2-(6'-carboxyhexyl)- cis-3-n-hexyl-cyclohexylamine characterized in that the com- pound obtained by addition of an equivalent of p-toluenesul- fonic acid to a mixture containing all the stereoisomers of 2-(6'-carbomethoxyhexyl)-3-n-hexyl-cyclohexylamine is crystal¬ lized with ethyl ether, whereby the R,S-cis-2-(6'-carbometh- oxyhexyl)-cis-3-n-hexyl-cyclohexylamine p-toluenesulfonate thus obtained is treated with a base thereby yielding R,S-cis- 2-(6'-carboxyhexyl)-cis-3-n-hexyl-cyclohexylamine•

3. A process for preparing R,S-trans-2-(6'-carboxyhexyl) cis-3-n-hexyl-cyclohexylamine characterized in that 2-(6'-car¬ boxyhexyl)-3-n-hexyl-cyclohexanone is reacted with lithium-tri sec-butylboronhydride in THF at -70°C thereby yielding a mix¬ ture of R,S-cis-2-(6'_--carboxyJιexyl)-cis-3-n-hexyl-cyclohexanol and R,S-cis-2-(6'-carboxyhexyl)-trans-3-n-hexyl-cyclohexanol, the thus obtained mixture is then treated with methanol and p- toluenesulfonic acid and chromatographed on silica gel using a 7:3 mixture of hexane: ethyl acetate as the eluent, whereby

R,S-cis-2-(6'-carbomethoxyhexyl)-cis-3-n-hexyl-cyclohexanol is separated which, after subsequent transformation into the cor¬ responding mesilate and after substitution with sodium azide and reduction with a metal catalyst and hydrogen and subsequent saponification yields R,S-trans-2-(6'-carboxyhexyl)-cis-3-n-hex cyclohexylamine.

4. The use of a compound of formula (I) according to Claim 1 or a pharmacologically acceptable salt thereof for pre- paring pharmaceutical compositions having antiplatelet, antith botic activity, in human and veterinary medicine, characterize in that in said formula : n = 2, m = 5, X = CH NH , Y = COOH; n = 2, m = 5, X = NHNH , Y = COOH; n = 2, m = 5, X = NH₂, Y = CH₂NH₂; n = 3, m = 5, X = NH , X = COOH: n = 3, m = 5, X = CH NH , Y = COOH; n = 3, m = 5, X = NH , Y ^*= CH NH ; n = 2, m = 4, X ^•*■*■= NH_2> Y = COOH; n ^*= 2, m = 6, X = NH , Y = COOH; n = 2, m = 7, X = NH_≥, Y = COOH.

5. The use of R,S-cis-2-(6'-carboxyhexyl)-cis-3-n-hexyl- cyclohexylamine, a compound of formula (I) according to Claim and a pharmacologically acceptable salt thereof having antipla let , antithrombotic activity, in human and veterinary medicin

6. The use of R,S-trans-2-(6'-carboxyhexyl)-cis-3-n- hexyl-cyclohexylami-ne, a compound of formula (I) according to Claim 1 and a pharmacologically acceptable salt thereof having antiplatelet, antithrombotic activity, in human and veterinary medicine.

7. A pharmaceutical composition having antiplatelet, antithrombotic activity,characterized in that it contains, as the active ingredient, a compound of formula (I) accord^¬ ing to Claim 1 or,a pharmacologically acceptable salt there- of.

8. A pharmaceutical composition having antiplatelet, antithrombotic activity containing, as its active ingredient a compound according to one of the Claims 4 to 6 or a phar¬ macologically acceptable salt thereof.