WO1994023726A1

WO1994023726A1 - Calmodulin blocking agent adducts useful as anti-platelet agents

Info

Publication number: WO1994023726A1
Application number: PCT/US1994/004277
Authority: WO
Inventors: Donald R. Vanderipe
Original assignee: Mallinckrodt Medical, Inc.
Priority date: 1993-04-22
Filing date: 1994-04-19
Publication date: 1994-10-27
Also published as: AU6707894A

Abstract

Novel anti-platelet compounds for therapeutic use in the prevention of rethrombosis and restenosis. The anti-platelet compounds are calmodulin blocking agents coupled to a long chain hydrophilic polymer.

Description

"CALMODULINBLOCKINGAGENTADDUCTSUSEFULASANTI-PLATELETAGE

Field of the Invention

The present invention relates to novel antiplatelet agents, and more particularly to novel antiplatelet agents for use in therapy for the prevention of rethrombosis and restenosis.

Background of the Invention

An intense interest exists in pharmaceutical drugs which demonstrate as their principal action the ability to antagonize the activation of platelets. This follows from the fact that activated platelets represent a major component of arterial blood clots and contain biologically active mediators, such as platelet derived growth factor. Platelet derived growth factor (PDGF) in turn serves to stimulate the proliferation of smooth muscle and other cells within blood vessel walls leading to a chronic narrowing of the blood vessel lumen. Activated platelets have the capability of adhering to regions of the vascular wall which are damaged such as that which occurs immediately prior to myocardial infarction or during balloon angioplasty catheterization. In addition to adherence, activated platelets can also aggregate and degranulate. Platelet aggregation is a primary/early event in the formation of arterial blood clots and this activity is amplified several fold when platelets contract and release their mediators, i.e. the process of degranulation.

Platelet degranulation is of great concern because platelets contain many of the mediators which, when released in the local environment, cause other platelets to aggregate and degranulate. This built-in amplification mechanism which helps blood clot formation following major arterial injury or trauma, is an undesirable phenomenon for chronic injuries to the blood vessel lining such as that which precedes myocardial infarction or acutely following angioplasty.

Aspirin, an antiplatelet drug, has been shown to be of value in reducing the incidence of repeat heart attacks in high risk patients. However aspirin is ineffective in preventing acute rethrombosis or reclosure after myocardial infarction or angioplasty. Other anti-platelet agents have likewise been found minimally effective in blocking some of the platelet-involved phenomena, such as exacerbation of myocardial infarction, reclotting following thrombolytic therapy, acute reclosure following angioplasty, and the late restenosis associated with angioplasty procedures.

In the case of rethrombosis, it is thought that as soon as a clot is dissolved, there is enough thrombin released from the dissolved clot to activate platelets and restart the clotting process. With PTCA, the same generally applies in the acute setting. Therefore, a therapeutically effective composition against platelet deposition and aggregation on the injured luminal surface is needed to preclude the release of biologically active mediators such as PDGF.

Since a number of stimuli exist which can activate platelets, e.g. catecholamines, adenosine diphosphate (ADP) , serotonin, thromboxanes, collagen, von Willibrand factor, and thrombin, to name a few, there are likewise a number of pathways for platelet adhesion, aggregation and degranulation. Agents which block some, but not all, of the above pathways are not completely effective as antiplatelet drugs. A relatively new approach to antiplatelet activity is directed to agents which block the Ilb/IIIa receptor, which principally is involved in platelet aggregation and which is primarily stimulated by circulating von Willibrand factor. Agents directed at this receptor are not completely effective, but do represent a rational approach to a therapeutic method. However, such agents based on technologies such as antibodies or receptor blocking peptides, have inherent disadvantages. Antibodies have been demonstrated to produce immune responses, i.e. murine antibodies have induced the so-called HA A (human anti-mouse immune) response. Peptides which block the lib/Ilia receptor are less immunogenic, however, they usually lack the required affinity for the receptor for maximal effect and their blood persistence is quite short requiring them to be administered by a constant infusion technique. Finally, none of the heretofore mentioned agents have included as a part of their in vivo efficacy the ability to block platelet degranulation, a most important feature since platelets contain several mediators which, when released, act to amplify local platelet adhesion and aggregation in the injured vascular segments.

In 1981, K-J Kuo et al., [Nature: 192. 9-11 (1981)], demonstrated that platelets could be made to change from their normal discoid shape to form spheres; a stable configuration unresponsive to most if not all of the external stimuli listed above. The mechanism of this effect was the inhibition of calmodulin as demonstrated by the phenothiazine type calmodulin inhibitors [chlorpromazine & trifuoroperazine] . It is probable that the calmodulin inhibition effect alters the orientation and the function of the platelet microtubules, actin and yosin to block contraction and hence degranulation, i.e. release of platelet contents. This phenothiazine-induced effect to cause platelets to form spheres was demonstrated in-vitro at concentrations of 25-50 micromolar. Although these concentrations would be relatively safe in vivo with respect to lethality to the animal or human, they would be expected to evoke significant to major tranquilization and/or depression in the subject since these drugs readily penetrate the blood brain barrier and would be depressant at 25-50 micromolar blood levels.

Therefore, although the mechanism of evoking platelet spherulization would be a most desirable pharmacologic approach to anti-platelet therapy, the attendant central nervous system (CNS) tranquilization and depression from the phenothiazines would preclude their general use in most above-mentioned clinical procedures.

Therefore, there remains a great need for broadly acting anti-platelet therapy for use in prevention of rethrombosis following thrombolytic therapy and to prevent acute reclosure and long term restenosis after percutaneous transluminal angioplasty (PTA) or percutaneous transluminal coronary angioplasty (PTCA) .

Summary of the Invention

The present invention discloses unique compounds comprising varying structural moieties joined in a manner which optimizes in vivo performance. The compounds include as a portion thereof calmodulin blocking chemical analogues which are capable of blocking most of the above listed means of platelet activation. The novel compounds of the present invention likewise include a portion which blocks or inhibits access of the molecules to the central nervous system (CNS) by preventing their transport through the blood brain barrier. Additionally, the varying structural moieties of the present examples provide for prolonged blood persistence of these agents after a single intravenous injection, such that only a few, i.e. (2-3), daily injections are required to maintain effective blood levels. When present in vivo in effective blood levels, the present compounds provide for anti-platelet effects which prove useful in preventing rethrombosis following thrombolytic therapy in cases of myocardial infarction, stroke, or other vascular clots or thrombi. It is also possible to provide through the present compounds for anti-platelet effects which are useful in preventing platelet aggregation and/or degranulation following invasive intravascular procedures such as, but not limited to, PTA and PTCA.

Although the above general summary represents the main attributes of the unique compounds of the present invention, other ancillary features will be appreciated by those skilled in the art and are to be included within the broad scope of this invention described in detail below.

Detailed Description of the Invention

The unique compounds of the present invention are composed of varying structural moieties, but preferably two or three, joined so as to optimize their in vivo performance. One portion of the compound consists of one of the many calmodulin inhibitor drugs, such as but not limited to chlorpromazine, trifluoperazine, triflupromazine, perphenazinae, chlorprothixine, haloperidol, penfluridol, pimozide, fluspirilen, quinacrine, imipramine, 2-chloroimipramine, chloridizepoxide, N-(6-aminohexyl)-5-chloro-l- naphthalenesulfonamide and naphthalenesulfonamide derivatives and fluphenazine or other structural series which demonstrate significant or potent in vivo anticalmodulin activity, connected structurally to a long chain hydrophilic moiety designed to preclude transport through the blood brain barrier. Typically this long chain moiety consists of a number of water soluble polymers as typified by, but not limited to, polyethylene glycol, dextran, polylysine, heparin, and other such hydrophilic polymers. As well, the polymeric moiety may be selected by molecular weight size to optimize the persistence in the blood by slowing the rate of metabolism and excretion. Optionally, to provide for enhanced activity, one may interpose between the calmodulin inhibitor and the hydrophilic polymer a linker. The nature of the linker would be of a hydrophobic or of an amphipathic nature, to facilitate the penetration of the anti-calmodulin drug into the platelets. Typically the linker may be aliphatic or partially or fully fluorinated to induce various levels of amphipathic potential on the active end of the molecule. Typically the linker ranges from 2-500 linear and/or branched carbons to allow for complete penetration to the core of the platelet, but optimally ranges from 2-100 linear carbon atoms. In practice, it would be expected that the amphipathic end would upon intravenous injection, bind to plasma proteins such as albumin. Subsequently this pool would equilibrate with the platelets so that the platelets would take up the amphipathic end of the molecule to inhibit the platelet calmodulin. As a result, the platelets assume the stabilized spherical configuration and become resistant to various external stimuli. The hydrophilic end of the molecule is carried into or is partially exposed on the exterior of the platelet and serves such purposes as inhibiting adverse blood or tissue interaction, prolonging circulation time [Tl/2 in the body] and serving as a carrier portion of the molecule to impart an inability to penetrate the blood brain barrier. The polyethylene glycol (hydrophilic) end of the molecule should be of a molecular weight between 100 and 6,000 and more preferably between 150 and 2,000. Hence the unique compound of the present invention possesses the desirable attributes of blocking platelet activity, avoiding the central nervous system, and prolonged intravascular circulation.

The method of making the unique compounds of the present invention having a molecular weight within the range of 800 to 6000 but preferably within the range of

1000 to 2500, is described in still greater detail in the illustrative examples which follow.

EXAMPLES

EXAMPLE 1:

I.) Preparation of Product -tvpe Compounds:

The following generalized reaction scheme demonstrates the procedures employed for the synthesis of Product I-type compounds, in which a 550, 1900 or 5000 molecular weight form of polyethylene glycol (PEG₅₅₀, PEG_lj9oo o^{r pEG}5,ooo) ^was attached to fluphenazine (FLU) via an ether linkage. As illustrated, this reaction scheme involves the initial synthesis of Precursor B (2-trifluoromethyl- 10-(3-[1-piperazinyl] propyl) phenothiazine) , which is then alkylated with the tosylated or bro inated form of methoxy-PEG to yield Product I-type compounds. Precursor B is also used in the synthesis of the Product IV-type compounds.

Figure 1. The generalized reaction scheme employed for the synthesis of Product I-type compounds. NOTE: Me-PEG-OTs was used in the synthesis of Product I₅₅₀ and Me-PEG-Br was used in the synthesis of Product I**_.,_90o and Product I 5,000 •

The synthetic procedures employed in the synthesis of the three pegylated forms of Product I are described in the following paragraphs. In addition, the synthetic procedures employed to prepare the various precursors that were required for the synthesis of the final products are also described.

A. ) Preparation of Precursor A (10-(3-chloropropyl, -2-(trifluoromethyl) -phenothiazine:

2- (Trifluoromethyl) -phenothiazine (10.00 grams, 0.037 mole, Janssen Chimica), l-bromo-3-chloropropane (7.87 grams, 0.050 mole, Aldrich), sodium hydride powder (1.20 grams, 0.050 mole, Aldrich) and N, N-dimethyl formamide (5 ml) were combined in toluene (200 ml) and allowed to reflux at approximately 110° C under nitrogen for 16 hours. After cooling, the toluene solution was removed by vacuum filtration by pouring the solution through a Buchner filtration funnel fitted with qualitative filter paper. The solvents were removed under aspiration vacuum using a rotary evaporator. The residue was pumped using oil pump vacuum for 16 hours to ensure complete removal of volatiles.

frseuxsor λ

Figure 2 . The reaction scheme employed for the synthesis of Precursor A. B.) Synthesis of Precursor B (2-trifluoromethyl-10- (3-[l-piperazinyl]propyl) phenothiazine

The crude precursor A (approximately 18 g) , piperazine (6.40 grams, 0.074 mole, Lancaster), tetrabutylammonium iodide (0.1 grams, 0.0002 mole Aldrich), potassium carbonate (10.22 grams, 0.074 mole) and methyl ethyl ketone (5 ml) were combined and allowed to reflux in toluene (100 ml) under nitrogen for twenty-four hours at roughly 110° C. Under these conditions, the reaction proceeded to nearly 90% completion as judged by thin layer chromatography using a solvent system of 9:1 CHC1₃/CH₃0H.

After cooling, the reaction mixture was poured through a Buchner filtration funnel fitted with qualitative filter paper and connected to house vacuum. The solid residue thus obtained was washed three times with toluene (50 ml each time) . The toluene extracts were combined and washed three times with water (50 ml each time) . The combined toluene extracts were then washed four times with 2N HC1 (75 ml each time) . The acid extracts were combined, extracted once with toluene (50 ml) , and then made alkaline by the addition of solid KOH at 0° C until a pH of 13 was reached. The addition of KOH resulted in the production of oily and aqueous layers (when the solution was warmed to room temperature) . The immiscible solution was extracted four times with diethylether (50 ml each time) . The ether extracts (into which the oil dissolved) were combined and extracted with water (50 ml each time) until a pH of 5-7 was obtained. The combined ether extracts were dried with sodium sulfate. For this procedure, anhydrous sodium sulfate was added to the combined ether extracts until the powder was free flowing on shaking. The ether solution was then filtered through a Buchner funnel as described above and concentrated using aspirator vacuum followed by oil pump vacuum for 24 hours. The resulting crude product (Precursor B) was a reddish-orange oil. The yield of crude Precursor B using this procedure was 54%.

Crude Precursor B was then further purified by column chromatography using the following procedure. A 6-cm (o.d.) glass column was wet-packed with 200 g of silica gel (EM Science, silica gel 60) in chloroform. The crude Precursor B (contained in minimal volume of 99:1 CHC1₃, /CH₃OH was applied to the column and successively eluted with the following: 500 ml of 99:1 CHC1₃/CH₃0H (solvent no. 1); 1000 ml of 98:2 CHC1₃/CH₃0H (solvent no. 2); 500 ml of 97:3 CHC1₃/CH₃0H (solvent no. 3); 500 ml of 96:4. CHC1₃/CH₃0H (solvent no. 4); 500 ml of 95:5 CHC1₃/CH₃0H (solvent no. 5); 250 ml of 90:10 CHC1₃/CH₃0H (solvent no. 6); 1000 ml of 80:20 CHC1₃/CH₃0H (solvent no. 7); and 1000 ml of 70:30 CHC1₃/CH₃0H (solvent no. 8). Sixteen ml fractions obtained following elution with solvent number 4 through solvent number 7 were collected in 16x125 mm glass tubes and combined. The solvents were then removed using vacuum aspiration and the resulting residue was dried using an oil pump vacuum for 48 hours.

The final yield of purified Precursor B using this procedure was 41%. The purified Precursor B remained a reddish-orange oil.

^**H NMR (200 MHZ, CDC1₃) : 7.30-6.80 (7H, m) ; 3.96 (2H, t, J=6.78 Hz); 2.85 (4H, t, J=4.80 Hz); 2.60-2.20 (6H, m) ; 1.93 (2H, quin., J=6.96 Hz).

_jcoa lolutne ntβiK

Precursor λ

Figure 3. The reaction scheme employed for the synthesis of Precursor B.

C. ) Synthesis of Precursor C (mono-methoxy-PEGccn tosylate:

Mono-methoxy-polyethylene glycol 550 (5.5 grams, 0.01 mole, Union Carbide), p-toluenesulfonyl chloride (30.0 grams, 0.157 mole, Lancaster), and pyridine (4 ml) were combined and stirred at room temperature for 16 hours.

After stirring, the reaction mixture was filtered using a Buchner filtration apparatus as described previously. The filtrate thus obtained was collected, concentrated via aspiration and dried using oil pump vacuum for 16 hours. The crude product thus obtained was further purified by column chromatography using the following procedure. A 5-cm (o.d.) glass column was wet-packed with 150 g of silica gel (EM Science, silica gel 60) in CHC1₃. The crude Precursor B (contained in minimal volume of CHCI₃, was applied to the column and successively eluted with the following: 100 ml of CHC1₃, (solvent no. 1); 500 ml of 99:1 CHC1₃/CH₃0H (solvent no. 2); 250 ml of 98:2 CHC1₃/CH₃0H (solvent no. 3); and 1000 ml of 97:3 CHC1₃,/CH₃0H (solvent no. 4). Sixteen ml fractions obtained following elution with solvent number 4 were collected in 16x125 mm glass tubes and combined. The solvents were then removed using vacuum aspiration and the resulting residue dried using oil pump vacuum for 24 hours.

The final yield of purified Precursor C using this procedure was 24%. Upon isolation, Precursor C was a colorless oil.

^**H NMR (200 MHz, CDC1₃) : 7.80 (2H, d, J=8.20 Hz); 7.30 (2H, d, J=9.50 Hz); 4.20-4.10 (2H, m) ; 3.90-3.30 (47H, m) ; 2.45 (3H, s) ; 2.04-1.92 (2H, m) .

D.) Synthesis of Precursor D (mono-methoxy-PEG, _onn bromide:

Thionyl bromide (1.62 ml, 0.0210 mole, Aldrich), contained in toluene (10 ml) , was added drop-wise into a solution containing mono-methoxy-polyethylene glycol 1,900 (10.2 grams, 0.0054 mole, Polysciences) in toluene (50 ml). This addition was performed at 0° C. Following the addition of thionyl bromide, triethyl a ine (6.4 ml, 0.046 mole) was added to the solution. The reaction mixture was allowed to reflux for 48 hours at approximately 110° C. The cooled reaction mixture was filtered through a 5-cm glass column contained a medium frit which was packed with 1-cm of celite. Filtration was facilitated using house vacuum. After collection, solvents were removed via vacuum aspiration. The resulting residue was dissolved in acetone (60 ml), filtered through fresh celite as described above, and concentrated to a volume of roughly 30 ml using a rotary evaporator. The crude product thus obtained was precipitated by the addition of diethyl ether (roughly 400 ml) . The resulting suspension was then stored at -20° C for 12 hours. The solid material was then removed by filtration using a Buchner filtration system, as previously described. Following filtration, the solid material was collected and combined with acetone (20 ml) and ether (roughly 300 ml) , and the resulting suspension stored at -20° C for 16 hours. The crude product

(Precursor D) was then collected via filtration using a Buchner filtration system, as previously described. The resulting residue was then dried under vacuum for 16 hours.

The crude Precursor D thus obtained was further purified via column chro atography using the following procedure. Three grams of the crude sample was applied to a wet- packed column (75 g silica gel moistened with CHC1₃) using a minimal volume of 99:1 CHC1₃/CH₃0H. The column was then successively eluted with the following: 500 ml of 99:1 CHC1₃/CH₃0H (solvent no. 1); 250 ml of 98:2 CHC1₃/CH₃0H (solvent no. 2); 250 ml of 97:3 CHC1₃/CH₃0H (solvent no. 3); 250 ml of 96:4 CHC1₃/CH₃0H (solvent no. 4); 250 ml of 95:5 CHC1₃/CH₃0H (solvent no. 5); and 250 ml of 94:6 CHCI₃/CH₃OH (solvent no. 6) . Sixteen ml fractions obtained following elution with solvent number 2 to solvent number 6 were collected in 16x125 mm glass tubes and combined. The solvents were then removed using vacuum aspiration and the resulting residue (Precursor D) was dried using oil pump vacuum for 24 hours.

The final yield of the reaction scheme used to prepare Precursor D was 19%.

E. ) Synthesis of Product I_ccn:

2-Trifluoromethyl-10-(3-[1-piperazinyl] propyl) phenothiazine (Precursor B, 1.0 grams, 0.00254 mole), mono-methoxy-PEG₅₅₀ tosylate (Precursor C, 0.5 grams, 0.00069 mole), potassium carbonate (2.0 g) , methyl ethyl ketone (5 ml) and a few crystals of potassium iodide were combined and allowed to reflux in toluene (90 ml) for five days under nitrogen at approximately 110° C. After cooling to room temperature, the reaction mixture was filtered using a Buchner filtration system, as previously described. The solvents were removed using aspiration vacuum and the residue dried using an oil pump vacuum for 24 hours.

The crude product was then purified by column chromatography using the following procedure. A 2.5-cm

(o.d.) glass column was wet-packed with 60 g of silica gel (EM Science, silica gel 60) in dichloromethane. The crude Product I₅₅₀ (contained in minimal volume of CH₂C1₂) was then applied to the column and successively eluted with the following: 50 ml of CH₂C1₂ (solvent no. 1); 50 ml of 99:1 CH₂C1₂/CH₃0H (solvent no. 2); 650 ml of 98:2 CH₂C1₂/CH₃0H (solvent no. 3); 400 ml of 97.5:2.5 CH₂C1₂/CH₃0H (solvent no. 4); 100 ml of 97:3 CH₂C1₂/CH₃0H (solvent no. 5); 100 ml of 96:4 CH₂C1₂/CH₃0H (solvent no. 6); and 400 ml of 95:5 CH₂C1₂/CH₃0H (solvent no. 7). Sixteen ml fractions obtained following elution with solvent number 7 were collected in 13x100 mm glass tubes and combined. The solvents were then removed using aspiration vacuum on a rotary evaporator and the resulting residue was dried using an oil pump vacuum for 24 hours.

Using this procedure, purified Product I₅₅₀ was obtained as a colorless oil in a yield of 46%.

*H NMR (200 MHz, CDC1₃) : 7.30-6.80 (7H, ) ; 4.10-3.85 (2H, m) ; 3.80-3.45 (48H, m) ; 3.44-3.35 (3H, m) ; 2.80-2.25 (10H, m) ; 2.10-1.80 (2H, m) .

Analysis: Calc. for C₄₅H₇₂N₃F₃0₁₂S : C, 57.74; H, 7.75; N, 4.49; S, 3.43; F, 6.09. Found: C, 57.44; H, 7.61; N, 4.56; S, 3.55; F, 6.15.

H_jCOi e-PEOOTi ' iβhwe. icfttx

—OMc

Figure 4. The reaction scheme employed for the synthesis of Product I₅₅₀.

Synthesis of Product I, 900'

To a solution containing mono-methoxy-PEG_1/900 bromide (Precursor D, 0.26 grams, 0.00013 mole) and two drops of N,N^'-dimethylformamide (DMF) in toluene (10 ml), was added a solution containing 2-trifluoromethyl-10-(3-[1- piperazinyl] propyl phenothiazine (Precursor B, 0.52 grams, 0.0013 mole) in toluene (5 ml). Potassium carbonate (0.59 grams, 0.0043 mole) was then added to the resulting solution and the mixture was allowed to reflux under nitrogen for 44 hours at approximately 110° C. The cooled reaction mixture was filtered through a 5-cm glass column contained a medium frit which was packed with 1-cm of celite. The filtrate was collected and crude Product I_1/900 was precipitated by the addition of diethyl ether (roughly 225 ml) . The mixture was stored at -20° C for 16 hours to complete precipitation. The mixture was then filtered using a Buchner filtration system, as previously described. The residue was washed two times with diethyl ether (20 ml each time) , and dried in a vacuum oven at room temperature for 6 hours.

The crude Product I_lj90o was further purified by column chromatography using the following procedure. A 1.5-cm (o.d.) glass column was wet-packed with 6.1 g of silica gel (EM Science, silica gel 60) in dichloromethane. The crude Product I₅₅₀ was then applied to the column as a concentrated solution in CHC1₃. The column was then successively eluted with the following: 5 ml of CHC1₃ (solvent no. 1); 25 ml of 99:1 CHC1₃/CH₃0H (solvent no. 2); 20 ml of 98:2 CHC1₃/CH₃0H (solvent no. 3); and 500 ml of 97:3 CHC1₃/ CH₃OH (solvent no. 4). Two ml fractions obtained following elution with solvent number 4 were collected in 10x75 mm glass tubes and combined. The solvents were then removed using aspiration vacuum and the resulting residue was dried using an oil pump vacuum for 48 hours.

The material thus obtained was recrystallized using the following procedure. The dried residue was dissolved in five ml of ethyl alcohol heated to 40° C. The solution was allowed to cool to room temperature and then stored at 5° C for 24 hours. Following removal of the ethyl alcohol, the residue thus obtained was dissolved in boiling methylene chloride (5 ml), filtered through 2-cm of celite contained in a 70 mm (o.d.) column plugged with cotton, and collected. The solution thus obtained was mixed with diethyl ether (30 ml), and stored for 16 hours at -20° C. The residue thus obtained was collected on a filter paper under vacuum and dried at room temperature under vacuum for 16 hours. The residue was subsequently dried for an additional 24 hours using oil pump vacuum.

This procedure resulted in an overall yield for Product I_lι900 of 34%.

^**H NMR (200 MHz, CDC1₃) : 7.30-6.80 (7H, m) ; 4.10-3.85 (2H, m) ; 3.84-3.45 (170H, m) ; 3.40-3.37 (3H, m) ; 2.70- 2.30 (10H, m) ; 2.10-1.80 (2H, m) .

Analysis : Calc . for C₁₀₆H₁₉₄N₃F₃O₄₂.₅S : C , 55 . 85 ; H , 8 . 58 ; N, 1.84; F, 2.50; S, 1.41. Found: C, 55.90; H, 8.56; N, 1.90; F, 2.67; S, 1.28.

The melting point of Product I_1/90o was approximately 45° C.

— CMc itftΛ

Figure 5. The reaction scheme employed for the synthesis of Product Iι,₉oo-

G.) Synthesis of Product 1- nnn:

A synthetic procedure analogous to that employed to prepare Product Iι,₉₀o was used to prepare Product I 5,000

The melting point of Product I₅,_0oo was approximately 47° C.

EXAMPLE 2:

II.) Preparation of Product II-type Compounds:

The following generalized reaction scheme demonstrated the procedures employed for the synthesis of Product II- type compounds, in which a 550, 1900 or 5000 molecular weight form of polyethylene glycol (PEG₅₀₀, PEG₁₉₀₀ or

PEG₅₀₀₀) was attached to fluphenazine (FLU) via an adipoyl linkage. As illustrated, this reaction scheme involves the initial synthesis of Precursor E (fluphenazine mono- adipate) , which is then combined with methoxy-PEG to yield Product II-type compounds.

The synthetic procedures employed in the synthesis of the three pegylated forms of Product II are described in the following paragraphs. In addition, the synthetic procedures employed to prepare any precursors that were required for the preparation of the final products are also described.

Precursor S

+ H—O— EQ—QMe DCC

DMAP, CH₂α₂

Figure 7. The generalized reaction scheme employed for the synthesis of Product II-type compounds.

A. ) Synthesis of Precursor E (fluphenazine mono- adipate) :

To fluphenazine (0.87 grams, 0.0020 mole, Sigma) in methylene chloride (22 ml) was added adipic acid (1.17 grams, 0.008 mole, Lancaster) and 4-dimethylaminopyridine (DMAP, 0.050 grams, 0.00041 mole, Aldrich) with stirring at room temperature. Dicyclohexyl carbodiimide (DCC, 0.50 grams, 0.0024 mole, Advanced ChemTech) in methylene chloride (10 ml) was added over a five-minute period. After 3.5 hours of stirring at room temperature, the precipitate which formed (dicyclohexyl urea, DCU) was removed by pouring the solution through a Buchner filtration funnel fitted with qualitative filter paper and connected to house vacuum. The filtrate was collected and washed three times with water (20 ml each time) . The aqueous portions were collected and extracted two times with methylene chloride (20 ml each time) . The combined organic portions were then dried using magnesium sulfate (as described previously for the preparation of Precursor B) , and filtered using a Buchner funnel apparatus under house vacuum. The filtrate was then concentrated using a rotary evaporator and the residue thus obtained was dried using an oil pump vacuum for 24 hours.

The crude Precursor E thus obtained was further purified via column chromatography as follows. A 2.5-cm (o.d.) glass column was wet-packed with 22 g of silica gel (EM Science, silica gel 60) in CHC1₃. The crude Precursor E (contained in minimal volume of CHC1₃) was then applied to the column and eluted with 400 ml of 98:2 CHC1₃/CH₃0H. Ten ml fractions were collected in 13x100 mm glass tubes and combined. The solvents were then removing using aspiration vacuum on a rotary evaporator. The resulting residue was dried using an oil pump vacuum for 24 hours, yielding purified Precursor E as a thick reddish-brown oil.

^XH NMR (200 MHz, CDC1₃) : 7.30-6.80 (7H, m) ; 4.19 (2H, t; J = 5.05 Hz); 3.96 (2H, t; J = 6.59 Hz); 2.80 (2H, t; J = 5.30 Hz); 2.70-2.40 (10H, m) ; 2.35 (2H, t; J = 6.23 Hz); 2.23 (2H, t; J = 5.72 Hz);.2.03 (2H, quintet; J = 7.43 Hz) ; 1.85-1.55 (4H, m) .

^:H nmr of fluphenazine (200 MHz, CDC1₃) : 7.30-6.80 (7H, m) ; 3.96 (2H, t, J=6.60 Hz); 3.64 (2H, t, J=5.13 Hz) ; 2.60-2.30 (12H, m) ; 1.94 (2H, q, J=7.00 Hz).

B.) Synthesis of Product II, 900 ^■

To a solution of mono-methoxy-polyethylene glycol 1,900 (0.25 grams, 0.00013 mole, Polysciences) and 4- dimethylaminopyridine (0.016 grams, 0.00013 mole, Aldrich) in methylene chloride (~-5 ml) was added a solution of dicyclohexyl carbodiimide (0.10 grams, 0.00050 mole) in methylene chloride (10 ml), followed by a solution of fluphenazine mono-adipate (Precursor E, 0.28 grams, 0.00050 mole) in methylene chloride (roughly 10 ml) . The entire solution was allowed to stir at room temperature under a drying tube for 112 hours (the reaction was essentially completed in 16 hours) .

The reaction mixture was filtered through 2-cm of celite contained in a 70 mm (o.d.) column plugged with cotton, and collected. The filtrate thus obtained was concentrated under aspirator vacuum. The residue was then triturated with acetone (10 ml), and the resulting acetone suspension was filtered through celite as described previously. The filtrate was combined with diethyl ether (250 ml) and stored at -20° C for 24 hours to complete precipitation. The crude polymeric material was filtered using a Buchner filtration apparatus, washed with additional ether (10 ml) , and dried under vacuum for 16 hours at room temperature. The product thus (a tan- brown film/foam material) was dissolved in anhydrous ethanol (roughly 15 ml) , cooled in an ice bath to initiate crystallization and stored at -20° C for 16 hours. The purified product was obtained via filtered using a Buchner filtration apparatus and dried in a vacuum oven for 7 hours at room temperature. The product was then dried an additional 48 hours using an oil vacuum pump.

This procedure resulted in an overall yield for Product II_lj900 of 55%. The melting point of Product II_lf90o was approximately 45° C.

Analysis: Calc. for C₁₁₄H₂₀₆F₃N₃O₄₆.₅S: C, 55.84; H, 8.47; N, 1.71; F, 2.32; S, 1.31. Found: C, 55.73; H, 8.51; N, 1 . 51 ; F , 2 . 03 ; S , 1 . 24 .

C. ) Synthesis of Product II ..*,,„ _{pure 1>900}:

Product II-.,₉oo was also prepared using mono-methoxy- polyethylene glycol_1/900 which was further purified following delivery from the supplier. The Product II thus obtained was referred to as Product II_{ultra pure 1/90}o• The methods employed to purify mono-methoxy-polyethylene glycol₁₍₉₀₀ (Precursor F) and to prepare Product Il_uι_{tra pUr}β _lr90o are described in a subsequent section.)

D.) Purification of mono-methoxy-polvethylene qlycoli 900'

Mono-methoxy-polyethylene glycols provided by Polysciences, Inc. are contaminated with 5-10% uncapped polyethylene glycols (as assessed via thin layer chromatography) . Attempts were made to make pure mono- methoxy-polyethylene glycols free of the diols using column chromatography.

A 5-cm (o.d.) column was wet-packed with 98 grams silica gel (Merck Silica Gel Co.) in chloroform. A sample of mono-methoxy-polyethylene glycol_1#900 (5.0 grams, Polysciences) was dissolved in a minimum quantity of 99:1 CHC1₃/CH₃0H and applied to the column. The column was then eluted successively with the following: 250 ml of 99:1 CHC1₃/CH₃0H (solvent no. 1) ; 250 ml of 98:2 CHC1₃/CH₃0H (solvent no. 2) ; 250 ml of 97:3 CHC1₃/CH₃0H (solvent no. 3) ; and 500 ml of 96:4 CHC1₃/CH₃0H (solvent no. 4) . Eight ml fractions obtained following elution with solvent number 2 were collected in 13x100 mm glass tubes and combined. The solvents were then removed using aspiration vacuum and the resulting residue was dried using an oil pump vacuum for 48 hours.

The procedure results in a 66% yield of ultra-pure mono- methoxy-polyethylene glycol-.,₉₀₀.

E. ) Preparation of Product H„u„ _{pure 1#900}:

Dicyclohexyl carbodiimide (0.17 grams, 0.00083 mole) in methylene chloride (10 ml) was added to a solution of methylene chloride (5 ml) containing pure mono-methoxy- polyethylene glycol_1>90o (0.50 grams, 0.00026 mole) and 4- dimethylaminopyridine (0.033 grams, 0.00027 mole) . Fluphenazine mono-adipate (Precursor E, 0.45 grams, 0.00080 mole) in methylene chloride (10 ml) was then added to this solution. This reaction mixture was stirred at room temperature under a drying tube for 45 hours (the reaction was completed in 16 hours) . The crude mixture was filtered through celite as described previously to remove dicyclohexyl urea. The filtrate was concentrated under aspirator vacuum and the residue was triturated with acetone (10 ml) . The acetone solution was again filtered through celite, mixed with diethyl ether (roughly 240 ml), and was stored at -20° C for 64 hours to precipitate the polymeric products.

The polymeric materials were filtered using a Buchner filtration apparatus and washed with three times with diethyl ether (20 ml each time) . The precipitate was filtered again and dried in a vacuum oven at room temperature for 16 hours. This product thus obtained was relatively pure with the exception of traces of polar materials . The product was then dissolved in a minimum quantity of CHC1₃ and applied to a glass column wet-packed with 8 grams of silica gel (Merck Silica Gel Co.) in CHCI₃. The column was eluted with 50 ml of CHC1₃, followed by roughly 250 ml of 98:2 CHCI₃/CH₃OH. The filtrate thus obtained was concentrated under vacuum aspiration to yield a greenish-yellow oil. The oil was dissolved in acetone (5 ml) and mixed with diethyl ether (120 ml), after which it was stored at -20° C for approximately three hours to precipitate the product. The purified Product II_uι_tra p_{ure 1}.9₀₀ was filtered using a Buchner filtration apparatus as described previously and washed with diethyl ether (50 ml) . The material was then dried in a vacuum oven at room temperature for 16 hours, after which it was dried via oil pump vacuum for 24 hours.

This procedure resulted in an overall yield for Product Iuitra pure 1.900 o^f 39%• ^τhe melting point of Product I_{ultra purβ} ₁,₉0₀ was approximately 45° C.

^lH NMR (200 MHz, CDC1₃) : 7.30-6.90 (7H, m) ; 4.20 (2H, m) ; 3.95 (2H, m) ; 3.85-3.45 (180H, ) ; 3.38 (3H, m) ; 2.60- 2.30 (10H, m) ; 1.76 (2H, m) .

Analysis: Calc. for C_n4H₂₀₆F₃N₃O₄₆.₅S: C, 55.84; H, 8.47;

N, 1.71; F, 2.32; S, 1.31. Found: C, 55.66; H, 8.55; N, 1.70; F, 2.29; S, 1.40.

F. ) Synthesis of Product Il_^n and Product lie „„_■.:

The synthetic procedures used to prepare Product II_50o and Product₅,_ooo were analogous to those used to prepare Product I-t.goo*

EXAMPLE 3: III.) Preparation of Product V-type Compounds:

The following generalized reaction scheme demonstrated the procedures employed for the synthesis of Product IV- type compounds, in which a 550, 1900 or 5000 molecular weight form of polyethylene glycol (PEG₅₀₀, PEG₁₉₀₀ or

PEG_50oo) was attached to a modified form of fluphenazine via an ester linkage. As illustrated, this reaction scheme involves the initial synthesis of Precursor B (2- trifluoro-methyl-10- (3- [1-piperazinyl] propyl) phenothiazine) , which is then reacted with ethyl acrylate to yield Precursor F. Finally, Precursor F was combined with methoxy-PEG to yield Product IV-type compounds.

Figure 8. The generalized reaction scheme employed for the synthesis of Product IV-type compounds.

The synthetic procedures employed in the synthesis of the three pegylated forms of Product IV are described in the following paragraphs. In addition, the synthetic procedures employed to prepare the various precursors that were required for the synthesis of the final products are also described.

A. ) Synthesis of Precursor B (2-trifluoromethyl-10-(3* fl- piperazinyll propyl) phenothiazine:

(NOTE: The synthesis of Precursor B is described above) ,

B. ) Synthesis of Precursor G (4-{3- \ 2 -(trifluoromethyl)- 10-phenothiazinyll-propyl)-1-piperazine-propionic acid:

Ethyl acrylate (5 ml, 0.046 mole) was added to a solution of 2-(trifluoromethyl-10-(3-[1-piperazinyl] propyl phenothiazine (Precursor B, 1.2 grams, 0.003 mole) in ethyl acetate (40 ml) and ethanol (4 ml), and the mixture stirred for 16 hours. The solvents were removed via aspiration using a rotary evaporator and the resulting residue was dried using an oil pump vacuum for 24 hours. The product thus obtained was the crude ethyl ester of Precursor F.

^lH NMR (200 MHz, CDC1₃) : 7.30-6.80 (7H, m) ; 4.30-4.05 (4H, m) ; 3.98 (2H, t, J=6.95 Hz); 2.75 (2H, t, J=6.96 Hz); 2.70-2.40 (8H, m) ; 2.20-1.85 (2H, m) ; 1.40-1.15 (5H, m) .

3N NaOH (6 ml) and ethanol (30 ml) were combined with the ethyl ester Precursor F (0.6 g) and allowed to reflux at 80° C for 16 hours. After cooling to room temperature, methylene chloride (50 ml) and concentrated HC1 (sufficient to adjust the pH to 4-5) were added to the solution. The methylene chloride layer (which contained Precursor G) was removed, concentrated via vacuum aspiration on a rotary vacuum, and dried under oil pump vacuum for 24 hours.

This procedure resulted in an overall yield for Precursor G of 89%. The melting point of Precursor F was 135-137° C.

^XH NMR (200 MHz, DMSO) : 7.50-6.85 (7H, ) ; 4.0 (2H, t, J=6.20 Hz); 2.70-2.15 (14H, m) ; 1.80 (2H, t, J=6.20 Hz).

precursor B

Figure 9. The reaction scheme employed for the synthesis of Precursor G.

C. ) Synthesis of Product IV*;*-.,-.:

To a solution of 4-{3-[2-(trifluoromethyl)-10- phenothiazinyl] -propyl)-1-piperazine-propionic acid (G, 0.34 grams, 0.0007 mole), mono-methoxy-polyethylene glycol₅₅₀ (0.20 grams, 0.00036 mole, Union Carbide) and 4- dimethylaminopyridine (0.10 grams, 0.0008 grams, Aldrich) in methylene chloride (25 ml) was added solid dicyclohexyl carbodiimide (0.2 grams, 0.001 mole,

Advanced Che Tech) . The reaction mixture was stirred at room temperature for 120 hours, concentrated under aspirator vacuum to roughly 10 ml and filtered through celite as described previously. The filtrate was dried using aspiration vacuum and the residue was dissolved in acetone (10 ml) . The resulting solution was again filtered through celite and the solvent evaporated off via aspirator vacuum to yield a brown oil. The crude product was purified by in portions (0.150 grams, dissolved in 5 ml acetone) using preparative thin layer chromatography (1,000 microns, 20x20 cm, silica gel GF, Analtech) . The TLC plates were eluted with 95:5 CH₂C1₂/CH₃0H. The appropriate band was scraped, and the silica obtained extracted twice with methanol (25 ml each time) and filtered on a medium frit using house vacuum. The filtrate was then concentrated under aspirator vacuum. The residue thus obtained was dissolved in methylene chloride (10 ml) and filtered through celite as described previously. The solvents were evaporated by blowing nitrogen gently across the solution. The resulting residue was dried under high vacuum to yield Product IV₅₅₀, which was a brown oil. This procedure resulted in an overall yield for Product IV₅₅₀ of 41%, which was a viscous brown oil.

^!H NMR (200 MHz, CDC1₃) : 7.35-6.87 (7H, m) ; 4.40-4.15 (2H, m) ; 4.10-3.85 (2H, m) ; 3.84-3.50 (50H, m) ; 3.45-3.30 (3H, m) ; 2.85-2.55 (2H, m) ; 2.50-2.20 (8H, m) ; 2.10-1.80 (2H, m) .

Analysis: Calc. for C₄₈H₇₆F₃N₃0₁₄S: C, 57.18; H, 7.60; N, 4.17; S, 3.18; F, 5.65. Found: C, 57.02; H, 7.42; N, 4.55; S, 3.36; F, 6.35.

D.) Synthesis of Product IV_{C nnn} :

4-{3-[2- (trifluoromethyl)-10-phenothiazinyl] -propyl)-1- piperazine-propionic acid (G, 0.4 grams, 0.00086 mole), mono-methoxy-polyethylene glycol₅,₀₀₀ (1.5 grams, 0.0003 mole, Polysciences) and 4-dimethyl-aminopyridine (0.1 grams, 0.0008 mole) in methylene chloride (30 ml) were combined and stirred at room temperature for two minutes. Dicyclo-hexyl carbodiimide (0.2 grams, 0.001 mole) was then added to the reaction mixture. The final reaction mixture was then stirred at room temperature for one week, followed by filtration through celite as describe previously. The filtrate thus obtained was concentrated using vacuum aspiration. The resulting residue was dissolved in acetone (25 ml) and then filtered through celite. Diethyl ether (450 ml) was then added to the solution, which was then stored for 16 hours at -20° C to initiate precipitation of crude Product IV_5/000. The crude product was collected via a Buchner filtration apparatus as described previously and dried in a vacuum over for 16 hours. The crude product was then dried an additional 7 hours under oil pump vacuum. The residue thus obtained was dissolved in warm ethanol (50 ml) and then cooled to 5° C for 16 hours to initiate precipitation. The resulting material was filtered using a Buchner filtration apparatus, washed with cold ethanol (20 ml, maintained at -20° C) and diethyl ether (10 ml), and dried in a vacuum oven at room temperature for 16 hours.

This procedure resulted in an overall yield for crude Product IV_5/000 of 79%. The melting point of crude Product IV_5j000 was 46-50° C.

The crude Product lV_5/000 thus obtained was further purified via column chromatography as follows. A 2.0-cm (i.d.) glass column was packed with 25 grams of silica gel (EM Science, silica gel 60) in CH₂C1₂. A concentrated solution of crude Product IV_5/000 in CH₂C1₂ was applied to the column and successively eluted with the following: 50 ml of CH₂C1₂ (solvent 1); 100 ml of 99:1 CH₂C1₂/CH₃0H (solvent 2); 50 ml of 98:2 CH₂C1₂/CH₃0H (solvent 3); 50 ml of 97:3 CH₂C1₂/CH₃0H (solvent 4); 250 ml of 96:4 CH₂C1₂/CH₃0H (solvent 5); 100 ml of 95:5 CH₂C1₂/CH₃0H

(solvent 6); 100 ml of 94:6 CH₂C1₂/CH₃0H (solvent 7); and 300 ml of 93:7 CH₂C1₂/CH₃0H (solvent 8). Seven ml fractions were collected between application of solvent number 4 and solvent number 6 in 13x100 mm glass tubes and combined. The solvents were then removed using aspiration vacuum on a rotary evaporator. The resulting residue was dissolved in CH₂C1₂ (2 ml) , mixed with diethyl ether (30 ml) and stored at -20° C for 16 hours. The product was collected using a Buchner filtration apparatus and dried in a vacuum oven at room temperature for 16 hours. The product was then dried an additional 24 hours using oil pump vacuum. This procedure resulted in an overall yield for Product ^Ivs.ooo of 51%. The melting point of Product IV_5/000 was 46- 50° C.

^αH NMR (200 MHz, CDC1₃) : 7.25-6.88 (7H, m) ; 4.30-4.14 (2H, ) ; 4.12-3.96 (2H, m) ; 3.85-3.44 (454H, m) ; 3.42-

3.34 (3H, m) ; 2.80-2.60 (2H, m) ; 2.50-2.20 (8H, m) ; 2.10- 1.80 (2H, m) .

Analysis: Calc. for C₂₅₀H₄₈₀N₃O₁₁₅F₃S : C, 55.01; H, 8.87; N, 0.77; F, 1.04; S, 0.59. Found: C, 54.71; H, 8.95; N, 0.66; F, 1.03; S, 0.55.

E. ) Synthesis of Product IV, onn and Product IV„τ.,. _{pure 1>900}:

The synthetic procedures used to prepare Product IV_1/900 and Product lV_{ultra purβ 1(90}o were analogous to those used to prepare Product IV_5/000.

Since many modifications, variations and changes in detail may be made to the described embodiments, it is intended that all matter in the foregoing description be interpreted as illustrative and not in a limiting sense.

Claims

What is claimed is:

1. An anti-platelet compound for intravascular administration comprising pharmacologically active structural adducts of a calmodulin blocking agent, coupled to a long chain hydrophilic polymer whereby said compound is optimized to minimize its penetration of the blood brain barrier and to provide for prolonged vascular persistence.

2. The anti-platelet compound of claim 1 wherein said calmodulin blocking agent is selected from the group consisting of fluphenazine, triflupenazine, trifluperazine, chlorpromazine or triflupromazine, the linker is alkyl, fluoroalkyl or perfluroalkyl, and said hydrophilic polymer is polyethylene glycol.

3. The anti-platelet compound of claim 1 wherein said calmodulin blocking agent is fluphenazine, the hydrophobic linker is perfluoroadipic acid.

4. The anti-platelet compound of claim 1 wherein said anti-platelet compound blocks platelet aggregation.

5. The anti-platelet compound of claim 4 wherein said compound provides for inhibition of platelet aggregation and degranulation.

6. The anti-platelet compound of claim 5 wherein said compound is useful for adjunctive therapy with thrombolytic agents to prevent rethrombosis following reperfusion of myocardial infarctions.

7. The anti-platelet compound of claim 5 wherein said compound is useful for adjunctive therapy in percutaneous transluminal coronary angioplasty to prevent acute reclosure and thrombosis.

8. The anti-platelet compound of claim 5 wherein said compound is useful for adjunctive therapy in percutaneous transluminal angioplasty to prevent acute reclosure and thrombosis.

9. The anti-platelet compound of claim 5 wherein said compound is useful for adjunctive therapy in percutaneous transluminal coronary angioplasty or percutaneous transluminal angioplasty to prevent restenosis of the treated blood vessel.

10. The anti-platelet compound of claim 1 wherein the bonding of said calmodulin blocking agent to the hydrophilic polymer is an ether, amide or ester bond.

11. The anti-platelet compound of claim 1 wherein said calmodulin blocking agent portion of said compound is structurally situated on opposed sides of the hydrophilic polymer.

12. The anti-platelet compound of claim 1 wherein said calmodulin blocking agent portion of said compound is structurally situated on opposed sides of the hydrophilic carrier and bonded with a hydrophobic linker by ether bonds.

13. An anti-platelet compound for intravascular administration comprising pharmacologically active structural adducts of a calmodulin blocking agent, coupled to a long chain hydrophilic polymer by means of a hydrophobic or amphipathic linker whereby said compound is optimized to minimize its penetration of the blood brain barrier and to provide for prolonged vascular persistence.

14. The anti-platelet compound of claim 13 wherein the bonding of calmodulin blocking agent to said linker is an ether, amide or ester bond.

15. The anti-platelet compound of claim 13 wherein said calmodulin blocking agent is selected from the group consisting of fluphenazine, triflupenazine, trifluperazine, chlorpromazine or triflupromazine, the linker is alkyl, fluoroalkyl or perfluroalkyl, and said hydrophilic polymer is polyethylene glycol.

16. The anti-platelet compound of claim 13 wherein said calmodulin blocking agent is fluphenazine, the hydrophobic linker is perfluoroadipic acid.

17. The anti-platelet compound of claim 13 wherein said anti-platelet compound blocks platelet aggregation.

18. The anti-platelet compound of claim 16 wherein said compound provides for inhibition of platelet aggregation and degranulation.

19. The anti-platelet compound of claim 17 wherein said compound is useful for adjunctive therapy^' with thrombolytic agents to prevent rethrombosis following reperfusion of myocardial infarctions.

20. The anti-platelet compound of claim 17 wherein said compound is useful for adjunctive therapy in percutaneous transluminal coronary angioplasty to prevent acute reclosure and thrombosis.

21. The anti-platelet compound of claim 17 wherein said compound is useful for adjunctive therapy in percutaneous transluminal angioplasty to prevent acute reclosure and thrombosis.

22. The anti-platelet compound of claim 17 wherein said compound is useful for adjunctive therapy in percutaneous transluminal coronary angioplasty or percutaneous transluminal angioplasty to prevent restenosis of the treated blood vessel.

23. The anti-platelet compound of claim 13 wherein the bonding of said calmodulin blocking agent to the hydrophilic polymer is an ether, amide or ester bond.

24. The anti-platelet compound of claim 13 wherein said calmodulin blocking agent portion of said compound is structurally situated on opposed sides of the hydrophilic polymer.

25. The anti-platelet compound of claim 13 wherein said calmodulin blocking agent portion of said compound is structurally situated on opposed sides of the hydrophilic carrier and bonded with a hydrophobic linker by ether bonds.

26. The anti-platelet compound of claim 13 wherein the anticalmodulin agent is taken from the group of fluphenazine, trifluoperazine, chlorpromazine, triflupromazine, perphenazinae, chlorprothixine, haloperidol, penfluridol, pimozide, fluspirilen, quinacrine, imipramine, 2-chloroimipramine, chloridizepoxide, N-(6-aminohexyl) -5-chloro-l- naphthalenesulfonamide, other naphthalene- sulfonamide derivatives, or other structural series which demonstrate significant or potent in vivo anticalmodulin activity,

27. A method of providing for effective intravascular inhibition of platelet activity and minimizing central nervous system effects by providing anti¬ calmodulin agents coupled to hydrophilic polymers.

28. A method of providing for effective intravascular inhibition of platelet activity and minimizing central nervous system effects in warm blooded animals by providing anti-calmodulin agents coupled to hydrophilic polymers in a pharmaceutically acceptable sterile form for intravascular injection.

29. The anti-platelet compound of claim 1 wherein said anti-platelet agent is useful in inhibiting thrombosis in the arteries of the brain.

30. The anti-platelet compound of claim 13 wherein said anti-platelet agent is useful in inhibiting thrombosis in the arteries of the brain.