MXPA01000097A - Calcium channel blockers - Google Patents

Abstract

Compounds of formula (1) wherein m is 0, 1 or 2;wherein when m is 0, Z is 0;when m is 1, Z is N, and when m is 2, Z is C;Y is H, OH, NH2, or an organic moiety of 1-20C, optionally additionally containing 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo;each 11 and 12 is independently 0-5;13 is 0 or 1;each of R1, R2 and R3 is independently alkyl (1-6C), aryl (6-10C) or arylalkyl (7-16C) optionally containing 1-4 heteroatoms selected from the group consisting of halo, N, P, O, and S or each of R1 and R2 may independently be halo, COOR, CONR2, CF3, CN or NO2, wherein R is H or lower alkyl (1-4C) or alkyl (1-6C);n is 0 or 1;X is a linker;with the proviso that Y is not a tropolone, a coumarin,or an antioxidant containing an aromatic group and with the further proviso that if 13 is 0, neither R1 nor R2 can represent F in the para position;and are useful as calcium channel blockers. Libraries of these compounds can also be used to identify antagonists for other targets.

Description

CALCIUM CHANNEL BLOCKERS This application is a continuation in part of the application of E.U.A. Serial No. 09 / 107,037 filed on June 30, 1998 and now authorized, and the contents of which are incorporated herein by reference.

TECHNICAL FIELD The invention relates to compounds useful in the treatment of conditions associated with calcium channel function. More specifically, the invention relates to compounds containing benzhydryl and 6-membered heterocyclic portions which are useful in the treatment of conditions such as brain tilt and pain.

TECHNICAL BACKGROUND The original calcium channels have been classified by their electrophysiological and pharmacological properties as types T, L, N, P and Q (for reviews see McCIeskey, EW et al, Curr Topics Membr (1991) 39: 295-326, and Dunlap, K. et al, Trends Neurosci (1995) 18: 89-98). Type T channels (or activated by low voltage) describe a broad class of molecules that transiently activate negative potentials and are highly sensitive to changes in resting potential. Type L, N, P and Q channels activate more positive potentials (activated at high voltage) and exhibit different kinetic and voltage-dependent properties. There is some overlap in biophysical properties of the high voltage activated channels, consequently the pharmacological profiles are useful to distinguish them in an additional way. Type L channels are sensitive to dihydropyridine agonists and antagonists, N-type channels are blocked by the peptide toxin Conus geographus, the? -conotoxin GVIA and P-type channels are blocked by the peptide? -agatoxin IVA from venom of the funnel network spider Agelenopsis aperta. A fourth type of calcium channel activated with high voltage (type Q) has been described, although it is controversial! if the type Q and type P channels are different molecular entities (Sather, WA et al, Neuron (1995) 11: 291-303; Stea, A. et al, Proc Natl Acad Sci USA (1994) 91: 10576- 10580; Bourinet, E. et al, Nature Neuroscience (1999) 2: 407-415). Several types of calcium conductance do not fall exactly in any of the above categories and there is variability of properties still within a category suggesting that additional subtypes of calcium channels remain to be classified. Biochemical analyzes show that neuronal calcium channels activated with high voltage are heterooligomeric complexes consisting of three distinct subunits (ai, a2d and ß) (reviewed by De Waard, M. et al, Ion Channels (1997) vol.4). Narahashi, T. ed. Plenum Press, NY). The ai subunit is the main pore formation subunit and contains the voltage sensor and binding sites for calcium channel antagonists. The mainly extracellular a2 is linked by disulfide to the transmembrane of subunit d and both are derived from the same gene and are cut proteolytically in vivo. The β subunit is a hydrophilic, non-glycosylated protein with a high binding affinity to a cytoplasmic region of the a-i subunit. A fourth subunit,?, Is unique to the L-type calcium channels expressed in skeletal muscle T-tubules. The isolation and characterization of cDNAs that encode subunit? they are described in the patent of E.U.A. No. 5,386,025 which is incorporated herein by reference. Recently, each of these ai subtypes has been cloned and expressed, thus allowing for more extensive pharmacological studies. These channels have been designated as a-iA-a-n and a-is and correlated with the sub-types discussed above. The CC-IA channels are of the P / Q type; OC-IB represents N; a-ic, a '? D, «-IF V a? s represent L; aie represents a new type of calcium conductance, and a-iG-an represents members of the T-type family reported in Stea, A. et al, in Handbook of Receptors and Channels (1994), North, R.A. ed. CRC Press; Pérez-Reyes, et al, Nature (1998) 391: 896-900; Cribbs, L.L. et al, Circulation Research (1998) 83: 103-109; Lee, J.H. et al, Journal of Neuroscience (1999) 19: 1912-1921. The patent of E.U.A. No. 5,646,149 discloses calcium antagonists of the formula A-Y-B in which B contain a piperazine or piperidine ring directly linked to Y. An essential component of those molecules is represented by A, which must be an antioxidant; Piperazine or piperidine itself is said to be important. The exemplified compounds contain a benzhydryl substituent, based on known calcium channel blockers (see below). The patent of E.U.A. No. 5,703,071 describes compounds that are said to be useful in the treatment of ischemic diseases. A major portion of the molecule is a tropolone residue; among the permitted substituents are piperazine derivatives, including their benzhydryl derivatives. The patent of E.U.A. No. 5,428,038 describes compounds that are said to exert a neuro-protective and anti-allergic effect. These compounds are coumarin derivatives which may include piperazine derivatives and other 6-membered heterocycles. A substituent allowed on the heterocycle is diphenylhydroxymethyl. Thus, methods in the art for various indications that may involve calcium channel blocking activity have used compounds which incidentally contain piperidine or piperazine portions substituted with benzhydryl but impose additional substituents to maintain functionality. Certain compounds containing benzhydryl and piperidine or piperazine portions are known to be known calcium channel blockers and neuroleptic drugs. For example, Gould, R.J. et al, Proc Natl Acad Sci USA (1983) 80: 5122-5125 describes antischizophrenic neuroleptic drugs such as lidoflazine, fluspirilene, pimozide, clopimozide, and penfluridol. It has also been that fluspirilene binds to sites on L-type calcium channels (King, VK et al, J Biol Chem (1989) 264: 5633-5641) as well as N-type calcium current blocking (Grantham, CJ et al Brit J. Pharmacol (1944) 111: 483-488). In addition, lomerizine, as marketed by Kenebo KK, is a known calcium channel blocker. A review of publications that refer to lomerizine is found in Dooley, D., Current Opinion in CPNS Investigational Drugs (1999) 1: 116-125. The present invention is based on the recognition that the combination of a six-membered heterocyclic ring containing at least one nitrogen optionally coupled through a linker to a benzhydryl portion results not only in calcium channel blocking activity, but also in improved specificity for N-type channels, thereby making those compounds particularly useful for the treatment of brain tilt and pain. By focusing on those portions, useful compounds can be prepared in treatment indications associated with excessive calcium channel activity and combinations of libraries of compounds containing those compounds.

BRIEF DESCRIPTION OF THE INVENTION The invention relates to compounds useful in the treatment of conditions such as stroke, acute and chronic pain, epilepsy, hypertension, cardiac arrhythmias, and other indications associated with calcium metabolism. The compounds of the invention are benzhydryl derivatives of piperidine, piperazine, or morpholine with substituents which improve the calcium channel blocking activity of the compounds but which do not contain substituents which are antioxidants, trofolones or coumarins. Thus, in one aspect, the invention is directed to therapeutic methods using compounds of the formula: wherein m is 0.1 or 2; where when m is 0, Z is O, when rn is 1, Z is N, and when m is 2, Z is C; Y is H, OH, NH2, or an organic portion of C1-20, optionally containing additionally 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo; every 11 and 12 is independently 0-5; 13 is 0 or 1; each of R 1, R 2 and R 3 is independently C 1-6 alkyl, C 1 -io aryl, or C 1 β-arylalkyl optionally containing 1-4 heteroatoms selected from the group consisting of halo, N, P, O, and S or each one of R1 and R2 may independently be halo, COOR, CONR2, CF3, CN or NO2, wherein R is H or C1-4 lower alkyl or C alkyl; n is O or 1; X is a linker; With the proviso that Y is not a tropolone, a coumarin, or an antioxidant containing an aromatic group and with the additional proviso that if 13 is 0, none of R1 or R2 represents F in the para position. The invention is directed to methods for antagonizing calcium channel activity using the compounds of formula (1) and therefore for treating associated conditions. It will be noted that the conditions may be associated with abnormal calcium channel activity, or the subject may have normal calcium channel function which nevertheless results in an undesirable physical or metabolic state. In another aspect, the invention is directed to pharmaceutical compositions containing those compounds. The invention is also directed to libraries of combination compounds containing the compounds of formula (1) and to methods for evaluating those libraries of compounds for members that contain particularly potent calcium channel brazing activity or for members that antagonize other receptors. Compound banks may also have compounds of formula (1) wherein the above conditions do not apply.

MODES OF CARRYING OUT THE INVENTION The compounds of formula (1) useful in the methods of the invention exert their desirable effects through their ability to antagonize the activity of calcium channels. Although the compounds of formula (1) generally have this activity, the availability of a multiplicity of calcium channel blockers allows a nuanced selection of compounds for particular disorders. In this way, the availability of this class of compounds provides not only a general-purpose genus of indications that are affected by excessive calcium channel activity, but also provides a large number of compounds that can be exploited and manipulated for specific interaction with particular forms of calcium channels. The availability of recombinantly produced calcium channels of the types OC-IA-a and a-ts discussed above facilitate this selection procedure. Dubel, S.J. et al, Proc Natl Acac Sci USA (1992) 89: 5058-5062; Fujita, Y. et al, Neuron (1993) 10: 585-598; Mikami, A. et al, Nature (1989) 340: 230-233; Mori, Y. et al, Nature (1991) 350: 398-402; Snutch, T. P. et al, Neuron (1991) 7: 45-57; Soong, T. W. et al, Science (1993) 260: 1133-1136; Tomlinson, W. J. et al, Neuropharmacology (1993) 32: 1117-1126; Williams, M. E. et al, Neuron (1992) 8: 71-84; Williams, M.E. ei al, Science (1992) 257: 389-395; Pérez-Reyes, eí al, Nature (1998) 391: 896-900; Cribbs, L. L. e al., Circulation Research (1998) 83: 103-109; Lee, J. H. et al., Journal of Neuroscience (1999) 19: 1912-1921. In this way, although it is known that calcium channel activity is involved in a multiplicity of disorders, the types of channels associated with particular conditions are the subject of current data collection. The association of, for example, N-type channels, as opposed to other types, in a specific condition would indicate that the compounds of the invention that specifically target N-type receptors are more useful in this condition. Many members of the genus of compounds of formula (1) are prone to specifically target N-type channels. Other members of the genus can target other channels. Among the associated conditions in which excessive calcium blockage would be of therapeutic value are stroke, epilepsy, and chronic and acute pain. Other cardiovascular conditions include hypertension and a. cardiac rhythmias. Calcium is also involved in other neurological disorders such as migraine, epilepsy and certain degenerative disorders. The availability of libraries of compounds containing the compounds of formula (1) (including those to which the conditions do not apply) also provides a source of compounds that can be evaluated for activity relative to additional ion channels and receptors. Those channels and receptors are also associated with conditions that are amenable to treatment. Sodium channel blockers, for example, are useful as local anesthetics, and in the treatment of cardiac arrhythmias, as anticonvulsants, and in the treatment of periodic hyperkalemic paralysis. Potassium channel blockers are useful in the treatment of hypertension and cardiac arrhythmias; Several other receptors are associated with psychosis, schizophrenia, depression and apnea. In this way, the library of compounds of the invention is useful in standard evaluation techniques as a source of pharmaceutically effective compounds. The compounds of the invention can be synthesized using conventional methods. The schemes 1 and 2 are illustrative of said methods: SCHEME 1 (Z is N) OR II / N- + Br-X1-COOH Br -C - N N- Y Witting Hj / Pd OR II? CHX1- -c N- Y BH, F, CHX1-OH, -N N- Y 2 2 \ -X Alternatively, a carboxylic acid containing the benzhydryl moiety can be synthesized and then reacted with the piperazine (or piperidine) moiety and subsequently reduced. Under these circumstances, a f-bromo carboxylic acid is refluxed with triphenylphosphine in the presence of methyl nitrile and then treated with lithium hexamethyldisilazide in a solvent such as THF. The resulting unsaturated carboxylic acid containing the two phenyl substituents is then reduced as shown in scheme 1 with hydrogen on a palladium catalyst and then reacted with piperazine derivative (or piperidine) to form the amide. The amide can be reduced afterwards as shown above.

SCHEME 2 (Z is CH) HN V "" l + Br-x1-COOH *. Br -? I - C - N Y I. YMgX 1) Y1-NH2 2. eliminate OH 3. reduce 2) NaB (OAc) 3H f2CHX -CH2 - N \ Yf 2CHX1-CH2 N V-NHY The compounds of formula (1) are defined as shown in terms of the modalities of their various substituents: Z may be O, N or C wherein m has the suitable value, that is, 0 when m is 0, N when m is 1 or C when m is 2. When m is 2, one of the substituents Y is preferably H, OR, NR2, in which R is H, alkyl of C ß, or a Y can itself be C ß alkyl- Preferred forms of Z are N, and C where Y is H or OH. Y is H, OH or NH2, or an organic portion of C1-25, optionally containing additionally 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo. Preferred forms of at least one And include those comprising an aromatic ring system, including fused ring systems and rings containing one or more heteroatoms. Particularly preferred forms of at least one Y are those that include phenyl portions. The aromatic portions included within Y may be substituted or unsubstituted; the "substituents" may include Cr6 alkyl, halo, OR, SR, NR2, COOR, J CONR2 in which each R is independently H or C1-6 alkyl or the "substituents" may be CN, CF3, or NO2. This group of portions will be referred to herein as "substituents". Of course, if Z is O, Y is not present (m = 0). Preferred further embodiments of Y include: aminoindane, azulene, cyclohexane, cyclohexanol, hexahydroazepine, indane, indene, indazole, indole, indolazine, morpholine, phenothiazine, phenoxazine, piperidine, pyrrole, pyridine, pyrimidine, thionaphthene, thiomorpholine, thiazine and thiazole or those systems linked through an additional linker. When m is 2, the two groups Y may be the same or different and preferred forms are those discussed above. However, embodiments are particularly preferred where, when m is 2 and Z is C, Y is selected from the list mentioned above and the other Y is H or OH. R3 may be C1-6 alkyl, C or C aryl, or C16 arylalkyl, optionally containing 1-4 heteroatoms selected from the group consisting of N, P, O, S, and halo; preferred embodiments of R3 include methyl. Typically, 13 is 0 or 1. Since n may be 0 or 1, X may or may not be present. X is a suitable linker containing Cpo which may be saturated or unsaturated and may contain a ring. The linker may also contain one or two heteroatoms selected from N, O and S and may be substituted with the "substituents" listed above. Preferred embodiments of X include - (CH2) n in which n is 1-10, preferably 1-6. R1 and R2 may independently be C alquilo ar aryl alkyl of Cpo, or arylalkyl of C 7 - ββ optionally containing 1-4 heteroatoms and optionally containing any of the "substituents" set forth above or R and R 2 may themselves independently be said substituents; 11 and 12 are each independently 0-5, but preferably 0-3. Preferred embodiments of 11 and I2 include 1, wherein the substituent is in the para position (1 p) or 3 wherein the substituents are in the two ortho positions and the para position (3o, p) or 2 wherein the substituents they are in the meta positions (2 m). Preferred forms of R1 and R2 include phenyl, phenylalkyl, Cl, Br, I, CF3, amino and alkyl. In treatment methods using the compounds of formula (I), Y must be different from tropolone, a coumarin, or an oxidant containing an aromatic group. In addition, in those methods the compounds of formula (I) can not include those in which 13 is O and either R 1 or R 2 represents F in the para position. In the libraries of compounds containing compounds of formula (I), those conditions do not apply. Preferred compounds for use in the method of the invention include those of formulas (1a): wherein Z is N or CH; wherein each of n1 and n2 is independently 0 or 1; X1 and X2 are linkers; and Ar represents one or two substituted or unsubstituted aromatic or heteroaromatic rings, and of (1b): wherein Z is N or CH; wherein each of n1 and n2 is independently 0 or 1; X1 and X2 are linkers; and Cr represents one or two cyclic or heterocyclic aliphatic portions, substituted or unsubstituted, or consists of a substituted or unsubstituted cyclic or heterocyclic aliphatic portion and an unsubstituted or substituted aromatic or heteroaromatic moiety. Thus, formulas (1a) and (1b) are similar, except that the compounds of formula (1a) contain aromatic substituents linked to the 6-membered heterocyclic ring and those of (1b) contain cyclic aliphatic or heterocyclic portions. In each case, preferably when X2 is present, X2 represents a linker that separates the Ar or Cy portion of Z at a distance of 3-20Á, and may contain at least one heteroatom which is nitrogen or oxygen. Included in said linkers are amines and carbonyl functionalities, including amides. The linker can also be unsaturated or it can be an alkylene group. Typically, X2 is (CH2)? -8 or (CH2)? -5-CH = CH- (CH2) or -3-- Similarly, X1, when present, separates the benzhydryl portion of the nitrogen from the heterocyclic ring to a distance of 3-20Á and may contain a heteroatom. The preferred embodiments are similar to those for X2. In both cases, when there are two aromatic or heterocyclic portions, X2 must accommodate this and a typical modality is (CH2) or -6-CH, which may also contain a p-bond. Thus, in preferred forms of formulas (1a) and (1b), n1 is 1 and X1 is (CH2)? -5-CO (CH2) or -3, (CH2)? -5-NH (CH2) o-3, (CH _,)? - 5-CONH (CH2) o -3 and (CH2) 1-5-NHCO (CH2) o-3. Preferred embodiments for X2 are similar except that in cases where Ar or Cy represent two rings, the two rings are coupled to CH as the terminal portion of linker X2. When X1 and X2 are selected from those preferred embodiments, although it is preferred that 11 and 12 are both 0, substitution by R1 and R2 in the benzhydryl system is permitted as set forth in the foregoing description of the invention, and may also include, in those instances, a para-fluoro substituent. It is believed that the halogenation of the compounds of the invention is useful for modulating the half-life in vivo, and it may be advantageous to include halogen substituents such as R1 and R2. In formulas (1a) and (1b), said substituents may also be included on Ar and Cy. The compounds of the invention can also be supplied as pharmaceutically acceptable salts. The pharmaceutically acceptable salts include acid addition salts which can be formed from inorganic acids such as hydrochloric, sulfuric and phosphoric acid or from organic acids such as acetic, propionic, glutamic, glutaric acids, as well as acidic ion exchange resins .

Utility and administration For use as a treatment in animals, the compounds of the invention can be formulated as pharmaceutical or veterinary compositions. Depending on the subject to be treated, the mode of administration, and the type of treatment desired, for example, prevention, prophylaxis, therapy; The compounds are formulated in forms according to these parameters. A summary of such techniques is found in Remington's Pharmaceutical Sciences, most recent edition, Mack Publishing Co., Easton, PA. In general, for use in treatment, the compounds of formula (I) can be used alone, as mixtures of two or more compounds of formula (I) or in combination with other pharmaceuticals. Depending on the mode of administration, the compounds will be formulated into suitable compositions to allow easy delivery. The formulations can be prepared in a manner suitable for systemic or topical administration or local administration. Systemic formulations include those designed for injection (for example intramuscular injection, intravenous or subcutaneous) or can be prepared for transdermal, transmucosal or oral administration. The formulation will generally include a diluent such as, in some cases, adjuvants, pH regulators, preservatives and the like. The compounds can also be administered in liposomal compositions or as microemulsions. For injection, formulations can be prepared in conventional forms as liquid solutions or suspensions or as solid forms suitable for solution or suspension in liquid before injection or as emulsions. Suitable excipients include, for example, water, saline, dextrose, glycerol, and the like. Said compositions may also contain amounts of non-toxic auxiliary substances such as wetting agents or emulsifiers, pH regulating agents and the like, such as, for example, sodium acetate, sorbitan monolaurate, and so forth. Several sustained release systems for drugs have also been contemplated. Consult, for example, the patenle of E.U.A. No. 5,624,677. Systemic administration may also include relatively non-invasive methods such as the use of suppositories, transdermal patches, transmucosal delivery and intranasal administration. Oral administration is also suitable for compounds of the invention. Suitable forms include syrups, capsules, tablets, as understood in the art. For administration to humans or animals, the dosage of the compounds of the invention is typically 0.1-100 μg / kg. However, dosage levels are highly dependent on the nature of the condition, the condition of the patient, the judgment of the physician, and the frequency and mode of administration.

Methods of evaluation The compounds of the invention can be synthesized individually using methods known in the art per se, or as members of libraries of combination compounds. In general, the benzhydryl portion of the molecule, which typically contains any substituent R1 and R2, is coupled, along with any linker portion, to the nitrogen of the morpholine, piperazine or piperidine ring. This ring itself is generally suitably replaced before its coupling. Typically, the benzhydryl linker moiety is supplied containing a suitable residual electron withdrawing group, thereby effecting coupling to the nitrogen ring. In addition to condensing a halogenated derivative of a benzhydryl portion to the nitrogen-containing heterocycle, additional conventional forms can be used to condense relevant portions of the molecule. For example, a brominated form of benzhydryl substituted suitably can be converted to a Grignard reagent which can then be condensed with, for example, the morpholine, piperidine or piperazine ring extending to the nitrogen through the portion (CH2). ) nCHO in which n is an integer of 1-4. Alternatively, a bromoalkylated form of the nitrogen-containing heterocycle can be converted to a Grignard reagent and condensed with the suitably substituted diphenyl ketone. In addition, an aminoalkylated form of the nitrogen-containing heterocycle can be condensed with suitably substituted diphenyl ketone to obtain the imine which can then be reduced, if desired. Finally, the two phenyl portions associated with the benzhydryl group can be prepared separately and condensed to obtain benzhydryl alcohol using a Grignard reagent prepared from a phenyl group and the benzaldehyde substituted suitably. The benzylhydric alcohol can then be brominated or further extended by alkylation and condensed with the morpholine, piperidine or piperazine derivative. The synthesis of pools of combination compounds is now commonplace in the art. Suitable descriptions of such syntheses are found, for example, in Wentworth, Jr., P. et al., Current Opinion in Biol (1993) 9: 109-. 15; Salemme, F.R. ei al, Structure (1997) 5: 319-324. Compound banks contain compounds with various modalities of R1, R2, R3, X, Y and Z. Those libraries of compounds, which contain as few as 10, but typically from several hundred members to several thousand members, can then be evaluated for compounds that are particularly effective against a specific subtype of calcium channel. In addition, by the use of standard evaluation protocols, libraries of compounds can be evaluated for compounds that block additional channels or receptors such as sodium channels, potassium channels and the like. Methods for performing those evaluation functions are well known in the art. Typically, the receptor that will be targeted is expressed on the surface of a recombinant host cell such as human embryonic kidney cells. The ability of members of the libraries of compounds to bind to the receptor or channel is measured, for example, by the ability of the compound in the compound bank to displace a labeled linker ligand such as the ligand normally associated with the receptor or a antibody to the receptor. More typically, the ability to antagonize the receptor is measured in the presence of a suitable agonist and the ability of the compound to interfere with the signal generated is measured using standard techniques. In more detail, one method involves the binding of radiolabelled agents that interact with the calcium channel and subsequent analysis of equilibrium linkage measurements including, but not limited to, firing rates, shutdown speeds, Ka values and competitive bonding. other molecules. Another method involves evaluation for the effects of compounds by electrophysiological analysis in which individual cells are enclosed with a microelectrode and currents through the calcium channel are recorded before and after the application of the compound of interest. Another method, high performance spectrophotometric analysis, utilizes cell line loading with a fluorescent dye sensitive to intracellular calcium concentration and subsequent examination of the effects of compounds on the ability to depolarize with potassium chloride or other means to alter calcium levels intracellular The following examples are designed to illustrate but not to limit the invention.

EXAMPLE 1 Correlation of calcium channel blockade with the presence of a piperidine / piperazine ring Antagonist activity was measured using nystatin patch logs in human embryonic kidney cells that either stably or transiently express rat a-iB + -2b + ß.b channels with 5 mM barium as a load carrier. For transient expression, host cells, such as HEK 293 human embryonic kidney cells (ATCC # CRL 1573) are cultured in standard DMEM medium supplemented with 2mM glutamine and 10% fetal bovine serum. HEK 293 cells are transfected by a standard calcium-phosphate-DNA coprecipitation method using rat N-type calcium channel subunits aβB + ßib + a2d in a vertebrate expression vector (e.g., see Current Protocols in Molecular Biology). After an incubation period of 24 to 72 hours the culture medium is removed and replaced with external recording solution (see below). The whole cell patch fixation experiments are performed using an Axopatch 200B amplifier (Axon Instruments, Burlingame, CA) linked to a compatible IBM personal computer equipped with pCLAMP software. The external recording solution is 5-20 mM BaCI2, 1 mM MgCl2, 10 mM HEPES, 40 mM TEACI, 10 mM Glucose, 65 mM CsCl (pH 7.2). The internal pipette solution is 105 mM CsCl, 25 mM TEACI, 1 mM CaCI2, 11 mM EGTA, 10 mM HEPES (pH 7.2). The currents typically arise from a sustained potential of -100 mV to several test potentials. The data is filtered at 1 kHz and recorded directly on the hard disk of a personal computer. Leakage subtraction is carried out online using a standard P / 5 protocol. Currents are analyzed using pCLAMP versions 5.5 and 6.0. The current-voltage macroscopic relationships are adjusted with the equation l =. { 1 / (1 + exp (- (Vm-Vh) / S).}. X G - (Vm-Erev). Where Vm is the test potential, Vh is voltage at which half of the channels are activated, and S reflects the lack of steps of the activation curve and is an indication of the effective gate load movement.The inactivation curves are normalized to 1 and adjusted with 1 = 1/1 + exp ((Vm-Vh) / S) with Vm being the containment potential The results of three experiments were averaged The structures of most of the compounds tested are shown below: Penfluridol: Pimozid Halope Flunarizine: The above compounds showed effective blocking activity: Penfluridol has an IC5o of 5 μM; the block develops over 60-90 seconds at concentrations of 10 μM and is reversibly deficient (pKa = 9.0). Pimozide shows an IC50 of approximately 2-3 μM; the block develops in 90 seconds at 10 μM and is completely reversible (pKa = 7.32). More than 80% of the activity is blocked at 10 μM. Haloperidol has an IC50 of 90 μM and the block develops in less than 16 seconds. It is reversible within 15 seconds (pKa = 8.3). At concentrations of 10 μM, the blockage is approximately 10%. Flunarizine has an IC50 of < 1 μM; the block develops over approximately 120 seconds at a concentration of 10 μM and is reversed over 5 minutes. The block is 90-95% effective at 10 μM. On the other hand, they showed less activity: Prenylamine (IC5o > 40 μM); Pridinol (IC5o 400 μM); Primidone (IC50> 500 μM); and Piperidolate (IC5o> 300 μM), which have the following formulas: Prenylamine 1 BN- type: IC50 > 40uM OH Pridimol a1 BN- type: IC90 > 400uM Primidone a1 BN- type: IC50 > 500uM Piperidolate a1 BN- type: IC50 > 300 uM Additional compounds that showed high values for IC50 include: bupivacaine, tolylpiperazine, piperine, trifluoromethylphenothiazine, morpholineacetophenone, morpholinebenzophenone and chloroethylpiperazine, whose formulas are: Tolypiper Procaine Piperine Trifluoromethytphenothiaáne Mofholineacetophenone ofo ne enzop enone As shown, the compounds of formula (I) exhibiting activity comprise those in which the CH adhered to X is in turn linked to two phenyl rings and Y contains a phenyl ring, optionally substituted by halo.

EXAMPLE 2 Synthesis of illustrative compounds of formula (I) A. Synthesis of 6,6-diphenylhexanic acid 6-bromohexanic acid (7.08 g, 36.3 mmol) and triphenylphosphine (10 g, 38.2 mmol) were mixed in dry CH3CN (40 mL), heated to reflux overnight and allowed to cool to room temperature. The solution was concentrated under reduced pressure to give a viscous gel. Approximately 75 ml of THF was added to the reaction mixture and the walls of the flask were scraped with a spatula to initiate crystallization. The resulting solid was filtered under vacuum, washed with THF and dried under reduced pressure and used without further purification. This product (1.5 g) was suspended in dry THF (10 ml) and the flask was purged with N2 and cooled to -78 ° C. To the stirred reaction was added lithium hexamethyldisilazide (LiHMDS) (10 mL, 1 M in THF). The yellow solution was stirred at -78 ° C for 1 hour during which time the reaction darkened slightly. The cooling bath was removed and the reaction was allowed to warm to room temperature. The reaction was maintained at room temperature for 1 hour during which time the solution turned a dark red color and most of the solids went into solution. Benzophenone (0.54 in 3 ml THF) was added to the reaction and allowed to react overnight. The yellow solution was concentrated under reduced pressure to give a yellow solid. The resulting solid was partitioned between ether and 10% HCl. The organic layer was washed with water (2x) and extracted with 10% NaOH (3x). The combined aqueous base fraction was acidified with concentrated HCl to a pH of 4. The water layer was extracted with ether (3x) and the combined organic fractions were dried over Na2SO4. The ether was evaporated to dryness under reduced pressure to give a colorless oil which crystallized on standing to give a waxy solid, 6,6-diphenylhex-5-enoic acid, which was dissolved in 30 ml MeOH and mixed with Pd- C at 5% and placed in a Parr hydrogenator. The reaction vessel was purged with hydrogen and pressurized to 4.22 kg / cm 2 nanometer and reacted at room temperature for 4 hours. The reaction mixture was formed in samples and analyzed by TLC. If the TLC when inked with KMnO4 showed a positive test for alkenes the mixture was re-subjected to the reaction conditions. The solution was then filtered through a plug of celite and the filtrate of methanol containing 6,6-diphenylhexanoic acid was concentrated under vacuum.

B. Reaction with substituted piperazine. 6,6-Diphenylhexanoic acid (0.4 mmole) was mixed with the desired N-alkylated piperazine (0.35 mmole) in THF (7 ml). EDC (0.5 mmol) and DMAP (cat) were added and the mixture was heated to 40 ° C with stirring overnight. The reaction was diluted with ethyl acetate and washed with water (4x) and 10% NaOH (3x) and dried over sodium sulfate and evaporated to dryness. The resulting residue was purified by column chromatography (silica gel 1: 1 hexanes: EtOAc), and the products were characterized by HPLC-MS. The piperazines used in the aforementioned process include phenylpiperazine, benzylpiperazine, benzhydrylpiperazine and piperazine substituted in the 1-position with BOC or f-Ch = CH2-. The resulting compounds contain a carbonyl adjacent to the piperazine ring nitrogen. These compounds are of formula (1) and exhibit calcium ion channel blocking activity.

C. Reduction of CO in X1 The compounds prepared in paragraph B were dissolved in THF (5 ml) dried and reacted with LiAIH (1 M in THF) and allowed to react for 6 hours. The reactions were quenched with EtOAc (15 ml) and extracted with water (5x) 10% NaOH (10x), saline (1x), dried over sodium sulfate and concentrated under reduced pressure.

Most of the products in this stage were > 80% pure. Those < 80% were purified by operating a short column (silica gel, 1: 1 hex: EtOAc).

D. Preparation of compounds of formula (1) from benzhydrylpiperazine derivatives N- (Diphenylmethyl) piperazine (0.5 mmol) was dissolved in dry THF (10 ml). K2CO3 powder and acid chloride of the formula Y'-CO-CI (0.7 mmoles) were added to each reaction flask. The reaction was stirred at room temperature for 2 hours and quenched with 10% NaOH (10 mL) and extracted with EtOAc (10 mL). The organic layer was washed with 10% NaOH (4x) and dried over sodium sulfate, concentrated, and purified by column chromatography (silica gel 1: 1 Hex: EtOAc) to give the desired amide. The acyl halides used in this procedure included cyclohexyl COCÍ, fCOCI and fCH = CHCOCI. To reduce the resulting amide, the above product was dissolved in dry 1 HF (5 ml) and reacted with L 1AIH 4 (1 M in THF) and allowed to react for 6 h. The reaction was quenched with EtOAc (15 mL). ml) and extracted with water (5x) 10% NaOH (10x), saline (1x), dried over sodium sulfate and concentrated under reduced pressure Most of the products in this step were> 80% Those <80% were purified by operating a short column (silica gel 1: 1 hex: EtOAc).

EXAMPLE 3 Synthesis of additional compounds of formula (1) Following the general procedure described above in Reaction Schemes 1 and 2, the following compounds of Formula (1) were synthesized as shown in Table A.

EXAMPLE 4 Channel blocking activities of various compounds of the invention Using the procedure set forth in the example, several compounds of the invention were tested for their ability to block N-type channels of calcium ions. The results are shown in tables 1-3, where IC50 is given in μM (micromolar). Table 1 represents results for compounds of formula (1 a) wherein Z is CH; Table 2 represents results for compounds of formula (1 a) wherein Z is N; and Table 3 represents the results for compounds of formula (1b) wherein Z is N. In all cases, 11, 12 and 13 are 0.

Claims (26)

NOVELTY OF THE INVENTION CLAIMS

1. - Use a compound of the formula: wherein m is 0, 1 or 2; where when m is 0, Z is O, when m is 1, Z is N, and when m is 2, Z is C; Y is H, OH, NH2, or an organic portion of C2o, optionally containing 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo; each I1 and 12 is independently 0-5; I3 is 0 or 1; each of R1, R2 and R3 is independently C? -6 alkyl, Cß-io aryl, or C7-β arylalk containing optionally 1-4 heteroatoms selected from the group consisting of halo, N, P, O and S or each of R1 and R2 can independently be halo, COOR, CONR2, CF3, CN or NO2, in which R is H or lower alkyl of C-O alkyl of C-? -6; n is 0 or 1; X is a linker; with the proviso that Y is not a tropolana, a coumarin, or an antioxidant containing an aromatic group and with the additional proviso that if I3 is 0, neither of R1 nor R2 can be F in the para position, for manufacturing of a medicament for the treatment of conditions associated with calcium channel activity in a subject.

2. The use as claimed in claim 1 wherein at least one of R1, R2 and R3 is a halo substituent.

3. The use as claimed in claim 1 wherein the compound of formula (1) is of formula (1a) wherein Z is N or CH; wherein each of n1 and n2 is independently 0 or 1; X1 and X2 are linkers; and Ar represents one or two substituted or unsubstituted aromatic or heteroaromatic rings.

4. The use as claimed in claim 3 wherein Ar represents one or two unsubstituted phenyl portions.

5. The use as claimed in claim 3 wherein n2 is 1 and X2 represents a linker which moves Ar of Z at a distance of 3-20Á.

6. The use as claimed in claim 5 wherein n2 is 1 and X2 contains at least one heteroatom selected from N and O.

1. - The use as claimed in claim 5 wherein n2 is 1 and X2 represents - (CH2)? - ß- or - (CH2)? - 5-CH = CH- (CH2) or -3.

8. The use as claimed in claim 5 wherein Ar represents two phenyl portions and n2 is 1 and X2 is of the formula - (CH2) or -6-CH.

9. The use as claimed in claim 3 wherein I3 is 0.

10. The use as claimed in claim 3 wherein I1 and I2 are 0.

11. The use as the one it is claimed in claim 3 wherein n1 is 1 and X1 represents a linker that moves the benzhydryl portion of N to a distance of 3-20Á.

12. The use as claimed in claim 11 wherein n1 is 1 and X1 contains at least one heteroatom selected from 0 and N.

13. The use as claimed in claim 11 wherein n1 is 1 and X1 represents - (CH2)? - 8 or - (CH2) .- 5-CH = CH- (CH2) or -3--

14. The use as claimed in claim 1 wherein the compound of formula (1) is of the formula (1 b) wherein Z is N or CH; wherein each of n1 and n2 is independently 0 or 1; X1 and X2 are linkers; and Cy represents one or two substituted or unsubstituted cyclic or heterocyclic aliphatic portions or consists of a substituted or unsubstituted cyclic or heterocyclic aliphatic portion and an unsubstituted or substituted aromatic or heteroaromatic moiety.

15. The use as claimed in claim 14 wherein n2 is 1 and X2 represents that Cy moves away from Z at a distance of 3-20Á.

16. The use as claimed in claim 15 wherein n2 is 1 and X2 contains at least one heteroatom selected from N and O.

17. The use as claimed in claim 15 wherein n2 is 1 and X2 represents - (CH2)? -8- or - (CH2)? -5-CH = CH- (CH2) or -3.

18. Use as claimed in claim 14 where 13 is 0.

19. Use as claimed in claim 14, where 11 and 12 are 0.

20. Use as the it is claimed in claim 14 wherein n1 is 1 and X1 represents a linker that separates the benzhydryl portion of N at a distance of 3-20Á.

21. The use as claimed in claim 20 wherein n1 is 1 and X1 contains at least one heteroatom selected from O and N.

22. The use as claimed in claim 20 wherein n1 is 1 and X1 represents - (CH2)? -8- or - (CH2)? -5-CH = CH- (CH2) or -3.

23. - A pharmaceutical composition for use in the treatment of conditions characterized by calcium channel activity whose composition comprises, in admixture with a pharmaceutically acceptable excipient, a dose amount of a compound of the formula: wherein m is 0, 1 or 2; where when m is 0, Z is O, when m is 1, Z is N, and when m is 2, Z is C; Y is H, OH, NH2 or an organic portion of C 1-20, optionally containing additionally 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo; each of 11 and 12 is independently 0-5; 13 is 0 or 1; each of R1, R2 and R3 is independently C1-6 alkyl, C6-10 aryl, or C7-16 arylalkyl optionally containing 1-4 heteroatoms selected from the group consisting of halo, N, P, O, and S or each of R1 and R2 can independently be halo, COOR, CONR2, CF3, CN or NO2, in which R is H or C1-4 lower alkyl or C1-6 alkyl; n is 0 or 1; X is a linker; with the proviso that Y is not a tropolone, a coumarin, or an antioxidant containing an aromatic group and with the additional proviso that if 13 is 0, none of R1 or R2 can be F in the para position.

24. A library of compounds comprising at least 10 different compounds of the formula: wherein m is 0, 1 or 2; where when m is 0, Z is O, when m is 1, Z is N, and when m is 2, Z is C; Y is H, OH, NH, or an organic portion of C 1-20, optionally containing additionally 1-8 heteroatoms selected from the group consisting of N, P, O, S and halo; each of 11 and 12 is independently 0-5; 13 is 0 or 1; each of R1, R2 and R3 is independently C1-6 alkyl, C6-10 aryl or C7-16 arylalk optionally containing 1-4 heteroatoms selected from the group consisting of halo, N, P, O, and S or each of R1 and R2 can independently be halo, COOR, CONR2, CF3, CN or NO, in which R is H or C1-4 lower alkyl or C1-6 alkyl; n is 0 or 1; and X is a linker.

25. A method for identifying a compound that antagonizes a target receptor whose method comprises contacting host cells that exhibit said target receptor in the presence of an agonist for said receptor and with the members of the library of compounds as claimed in FIG. claim 14; evaluate the ability of the members of the compound bank to affect the response of the receptor to its agonist; and identifying as an antagonist any member of the compound bank that decreases the receptor response to its agonist.

26. The method as claimed in claim 25 wherein the receiver is an ion channel. t? «- 7¿t ..