WO1994025045A1

WO1994025045A1 - Cyclohexapeptidyl aminoalkyl ethers

Info

Publication number: WO1994025045A1
Application number: PCT/US1994/004736
Authority: WO
Inventors: James M. Balkovec; Frances Aileen Bouffard; James F. Dropinski
Original assignee: Merck & Co., Inc.
Priority date: 1993-05-04
Filing date: 1994-04-29
Publication date: 1994-11-10
Also published as: EP0697879A1; AU674233B2; CA2161149A1; EP0697879A4; US5741775A; JPH09500103A; AU6778194A

Abstract

A compound having formula (I) in which R1 is an aminoalkyl group and (a) is an acyl group, and salts thereof. The compounds have antibiotic activity.

Description

TITLE OF THE INVENTION

CYCLOHEXAPEPTIDYL AMINOALKYL ETHERS

BACKGROUND OF THE INVENTION

The present invention is directed to antibiotic compounds having a superior combination of properties. Echinocandin B and related fermentation metabolites are known to have antifungal

properties when tested in vitro. However, some of the compounds are toxic when tested in vivo and some show lytic activity on human red blood cells thus rendering them undesirable for therapeutic use. Some derivatives have been reported as more useful compounds for human therapeutic use. Most of the derivatives are Hpophilic side chain analogs at the α-amino-nitrogen of the hydroxyomithine residue or ethers at the hemiaminal position. A number of aminoalkyl ethers were prepared and are the subject of Belgian patent No. 859,067 (1978) and Belgian patent No. 851 ,310 (1977).

According to the present invention it has been discovered that when the aminoalkyl ether is that derived not from echinocandin B but from a cyclohexapeptide compound in which one of the nuclear amino acids is glutamine instead of threonine, the compound has superior antibiotic activity in vivo. Moreover, the compound is substantially non-toxic and also non-lytic toward human blood cells, thereby rendering the compound adaptable for human therapy which has not been possible with many compounds even though they might be active.

The compounds of the present invention are aminoalkyl ethers at the 5-position of omithine and acyl derivatives at the N² position of the omithine in the cyclopeptide nucleus and which may be represented by the formula (I) (SEQ ID NO 1)

In this and succeeding formulas,

R₁ is -CH₂CH(NH₂)CH₂R^I

-C_nH₂nNR^IIR^III

-(CH₂)_1-3CH(NH₂)R^IV or -C_nH₂nNHR^V

wherein n is 2 to 6;

R₂ is

wherein

R^a is C₁-C₁₀alkyl; or

(CH₂)_qNR^bR^c wherein

R^b and R^c are independently H, C₁-C₁₀ alkyl or R^b and R^c taken together are or

wherein R^d is C₁ -C₁₆ alkyl,

phenyl or benzyl

R^I is -OH

-NH₂

-NHC(=NH)NH₂

-NHC(=NH)(CH₂)_0-3H R^II is -H

-C₁ -C₄ alkyl or

-benzyl

R^III is -H

-C₁ -C₄ alkyl

-benzyl or

R^II and R^III together are -(CH₂)₄- or -(CH₂)₅-

R^IV is -C₁ -C₄ alkyl

-CONH₂ R^V is -C(=NH)NH₂

-C(=NH)(CH₂)_0-3H

-(CH₂)_2-4NH₂

-(CH₂)_2-4OH

-CO(CH₂)_{1 -3}NH₂

-(CH₂)_2-4NH(C=NH)NH₂

-(CH₂)_2-4NH(C=NH)(CH₂)_0-3H

p is an integer from 1 to 2, inclusive and

q is an integer from 2 to 4, inclusive.

The expression "alkyl" is intended to include branched and cyclic as well as straight chain radicals.

Salts of the foregoing are also within the scope of the present invention. Salts include acid addition salts and quaternary ammonium salts. These salts are formed at the amino function of the amino alkyl group. When the expression "Compound I" is employed, it is intended to embrace the salts.

Pharmaceutically acceptable salts as acid addition salts are those from acids such as hydrochloric, hydrobromic, phosphoric, sulfuric, maleic, citric, acetic, tartaric, succinic, oxalic, malic, glutamic, salicylic, lactic, gluconic, hydrocarbonic and the like, and include other acids related to the pharmaceutically acceptable salts listed in Joumal of Pharmaceutical Science, 66, 2 (1977).

The compounds in the scope of the present invention which have a highly desirable combination of properties of high effectiveness and/or low toxicity and other adverse side reactions are all aminoalkyl ethers at the 5-hydroxy position of the 4,5-dihydroxyomithine

component of the cyclopeptide. The amino group may be substituted or the alkyl portion may have other substituents but it is critical that the basic amino property of the group be retained.

The acyl substituent on the omithine nitrogen differs from natural products and known compounds in being an aromatic chain of at least two phenyl groups and further extended by substituents in the para position. Certain compounds may be named as echinocandins or pneumocandins. The compounds in which one of the amino acids of the cyclic peptide is glutamine instead of a second threonine and the side chain on the omithine nitrogen is 10,12-dimethylmyristoyl have been named as pneumocandins by Schwartz et al, J. Antibiot. 45, No. 12, 1853-1866 (1992), and reference is also found in J.M. Balkovec et al, Tetrahedron Let., 1992, 33, 4529-32. Thus, the natural product in which the nucleus is 4,5-dihydroxyornithine, threonine, 4-hydroxyproline, 3,4-dihydroxy-homotyrosine, 3-hydroxy glutamine and 3-hydroxyproline and the side chain is 10,12-dimethylmyristoyl is named pneumocandin B_o. Compounds of the present invention which differ in the substituent at the 5-hydroxy of omithine and in the side chain acyl may be named as derivatives of pneumocandin B_o.

The compounds of the present invention are white solids, soluble in a variety of organic solvents such as methanol, ethanol, dimethylformamide (DMF), dimethyl sulfoxide (DMSO) and the like and also in water.

The antibiotic properties may be utilized against fungi causing pathogenic mycotic infections such as Candida albicans, Candida tropicalis, and the like, Aspergillus fumigatus and other Aspergillus sp. Additionally, the compound is adapted to be employed for inhibiting or alleviating Pneumocystis carinii infections, prevalent in immune compromised patients and which have usually been fatal.

The structural aspects which distinguish the compounds of the present invention is the combination of an aminoalkyl group on the 5-hydroxyomithine of the cyclopeptide nucleus, the carboxamide group arising from the nuclear amino acid glutamine, and the side chain acyl group. For the desirable combination of properties, the amino acids of the nucleus are not changed. The aminoalkyl group may be varied provided that the aminoalkyl always has a basic amino group. These modifications are those which do not affect the fundamental and essential amino acids of the cyclopeptide. The compounds of the present invention may be prepared by aminoalkylation of a derivative of a natural product which is represented by the formula (A) (SEQ ID NO 1 )

with an aminoalkanol (or alkanolamine) or substituted aminoalkanol, R₁ OH wherein R₁ is an aminoalkyl or substituted aminoalkyl group in which the amino may be substituted or unsubstituted. When it is a substituted amino group, the substituent is such that it does not neutralize the basic amino group. The aminoalkylation is carried out in the presence of a strong acid in an aprotic polar solvent and the product isolated from the reaction mixture preferably by the use of reverse phase high performance liquid chromatography (HPLC).

The nucleus of the aminoalkyl ether and the starting material are the same since the amino acids of the peptide nucleus are not changed. Thus, both product and starting material have the same Sequence ID number.

R₁ OH may be substituted or unsubstituted. When unsubstituted, a protecting group optionally is placed on the amino group before the reaction is carried out and the protecting group removed after the etherifi cation is complete as hereinafter more fully described. When R ₁ is a substituted amino group, a substituted amino alcohol may be the reactant or alternatively an unsubstituted amino alcohol may be employed and the substituent subsequently put on the amino group.

The amino alcohol is generally employed in the form of an acid addition salt and is employed in an amount of from about 20 to 200 equivalents.

The reaction is carried out in the presence of a strong acid. Examples of strong organic acids are camphorsulfonic acid, p-toluenesulfonic acid, methanesulfonic acid or a mineral acid such as hydrochloric or hydrobromic acid. Hydrochloric and camphorsulfonic acids are preferred. Approximately 1 equivalent of the acid is employed.

A solvent is employed in carrying out the reaction.

Suitable solvents are aprotic solvents and include dimethyl sulfoxide (DMSO), dimethylformamide (DMF), 1-methyl-2-pyrrolidinone, hexamethylphosphoric triamide (HMPA), dioxane or combinations thereof. Dimethyl sulfoxide and dimethylformamide are preferred.

When the amino alcohol has a primary amino group, the group may be protected before it is used. Conventional protecting groups are employed. The carbobenzyloxy group (CBz) is the preferred group. In protecting the amino group with a carbobenzyloxy group, the group is placed on the amino group of R₁OH by

conventional means and the protected R₁OH, the cyclopeptide to be etherified and a strong acid, as used in the etherification using an unprotected R ₁ OH, are stirred together in a solvent such as those useful in the reaction employing an unprotected amino alcohol until substantial completion of the reaction. The progress of the reaction may be monitored by HPLC. After completion of the reaction, the reaction mixture is neutralized, diluted with water and then purified by HPLC to obtain an N-benzyloxycarbonyl aminoalkyl ether intermediate.

To obtain the desired aminoalkyl ether, the protected ether is hydrogenated under balloon pressure in the presence of

palladium/carbon in acetic acid, preferably for from one to several hours as may be monitored by analytical HPLC with 30 to 40 percent aqueous acetonitrile solvent system containing 0.1 % trifluoroacetic acid. The product is then recovered by first removing the catalyst and lyophilizing the filtrate to obtain the desired product as trifluoroacetate salt. The latter may be converted to a hydrochloride by passing a minimum volume aqueous solution thereof through an anion exchange column.

With substituted amino groups, if the substituent is not already on the amino alcohol, it may be placed on the amino group after the ether is formed by a method appropriate for the particular group and within the knowledge of those skilled in the art.

The ether product is isolated from the reaction mixture and is conveniently purified using HPLC techniques, including utilization of a reverse phase column. The eluants from HPLC are then concentrated and lyophilized as subsequently detailed. The elution is carried out using various concentrations of acetonitrile/water, starting at about 15 percent acetonitrile and then increasing the amount of acetonitrile. The eluting solutions generally contain 0.1 percent trifluoroacetic acid (TFA) or acetic acid and the product on isolation is found in the form of the salt.

The compounds of the present invention may be employed for the control of many fungi including the Candida species. The antifungal properties may be illustrated with the minimum fungicidal concentration (MFC) determination against certain Candida organisms in a microbroth dilution assay carried out in a Yeast Nitrogen Base (Difco) medium with 1 percent dextrose (YNBD). For carrying out the assay, Compound I is solubilized in 10 percent dimethyl sulfoxide (DMSO) and diluted to 2560 μg/ml. The compound is then diluted to 256 μg/ml in YNBD. 0.15 mL of the suspension is dispensed to the top row of a 96-well plate (each well containing 0.15 ml of YNBD) resulting in a drug concentration of 128 μg/ml. Two-fold dilutions are then made from the top row to obtain final drug concentrations ranging from 128 to 0.06 μg/ml.

The yeast cultures, maintained on Sabouraud dextrose agar are transferred to YN broth (Difco) and incubated overnight at 35°C with shaking (250 rpm). After incubation, each culture is diluted in sterile water to yield a final concentration of 1 -5 × 10⁶ colony forming units (CFU)/ml.

96-well microplates are inoculated using a MIC-2000 (Dynatech) which delivers 1.5 μl per well yielding a final inoculum per well of 1.5-7.5 × 10³ cells. The microplates are incubated at 35°C for 24 hours. The minimum inhibitory concentrations (MICs) are recorded as the lowest concentrations of drug showing no visible growth.

After recording the MIC, the plates are shaken to resuspend the cells. Thereafter, 1.5 μl samples from the wells in the 96-well microplate are transferred to a single well tray containing Sabouraud dextrose agar. The inoculated trays are incubated 24 hours at 35°C and then read for minimum fungicidal concentration (MFC). MFC is defined as the lowest concentration of drug showing no growth or less than 4 colonies per spot.

The in vivo effectiveness of the compounds against fungi may be seen by the experiment carried out in the following manner:

Growth from an overnight SDA culture of Candida albicans MY 1055 is suspended in sterile saline, the cell concentration determined by hemacytometer count and the cell suspension then adjusted to 3.75 × 10⁵ cells/ml. 0.2 milliliter of this suspension is administered I.V. in the tail vein of mice so that the final inoculum is 7.5 × 10⁴ cells/mouse. The assay then is carried out by administering aqueous solutions of Compound I (R₁ = -CH₂CH₂NH₂) at various concentrations intraperitoneally (I.P.), twice daily (b.i.d.) for four consecutive days to 18 to 20 gram female DBA/2 mice, which is previously infected with Candida albicans (MY 1055) in the manner described above. Distilled water is administered I. P. to C. albicans challenged mice as controls. After seven days, the mice are sacrificed by carbon dioxide gas, paired kidneys are removed aseptically and placed in sterile polyethylene bags containing 5 milliters of sterile saline. The kidneys are homogenized in the bags, serially diluted in sterile saline and aliquots spread on the surface of SDA plates. The plates are incubated at 35°C for 48 hours and yeast colonies are enumerated for determination of colony forming units (CFU) per gram of kidneys.

A harmful and potentially fatal side reaction of a number of dmgs including certain antibiotically active echinocandin compounds is red blood cell lysis which are not seen by compounds having the present nuclei are another advantage of the compounds of the present invention.

The compounds of the present invention may also be useful for inhibiting or alleviating Pneumocystis carinii infections in immune compromised patients. The efficacy of the compounds of the present invention for the therapeutic or anti-infective purposes may be demonstrated in studies on immunosuppressed rats in which Sprague-Dawley rats (weighing approximately 250 grams) are immunosuppressed with dexamethasone in the drinking water (2.0 mg/L) and maintained on a low protein diet for seven weeks to induce the

development of Pneumocystis pneumonia from a latent infection.

Before drug treatment, two rats are sacrificed to confirm the presence of Pneumocystis carinii pneumonia (PCP). Five rats (weighing approximately 150 grams) are injected twice daily for four days subcutaneously (sc) with Compound I in 0.25 ml of vehicle (distilled water). A vehicle control is also carried out. All animals continue to receive dexamethasone in the drinking water and low protein diet during the treatment period. At the completion of the treatment, all animals are sacrificed, the lungs are removed and processed, and the extent of disease determined by microscopic examination of stained slides for the presence of cysts. The prevention of or reduction of cysts are seen in slides of lungs of treated rats when compared with the number of cysts in lungs of untreated controls or solvent controls.

The outstanding properties are most effectively utilized when the compound is formulated into novel pharmaceutical

compositions with a pharmaceutically acceptable carrier according to conventional pharmaceutical compounding techniques.

The novel compositions contain at least a therapeutic antifungal or antipneumocystis amount of the active compound.

Generally, the composition contains at least 1 % by weight of Compound I or one of the components. Concentrate compositions suitable for dilutions prior to use may contain 90% or more by weight. The compositions include compositions suitable for oral, topical, parenteral (including intraperitoneal, subcutaneous, intramuscular, and

intravenous), nasal, and suppository administration, or insufflation. The compositions may be prepacked by intimately mixing Compound I with the components suitable for the medium desired. Compositions formulated for oral administration may be a liquid composition or a solid composition. For liquid preparations, the therapeutic may be formulated with liquid carriers such as water, glycols, oils, alcohols, and the like, and for solid preparations such as capsules and tablets, with solid carriers such as starches, sugars, kaolin, ethyl cellulose, calcium and sodium carbonate, calcium phosphate, koalin, talc, lactose, generally with lubricant such as calcium stearate, together with binders

disintegrating agents and the like. Because of their ease in

administration, tablets and capsules represent the most advantageous oral dosage form. It is especially advantageous to formulate the compositions in unit dosage form (as hereinafter defined) for ease of administration and uniformity of dosage. Compositions in unit dosage form constitute an aspect of the present invention and for injection take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles such as 0.85 percent sodium chloride or 5 percent dextrose in water and may contain formulating agents such as suspending,

stabilizing and/or dispersing agents. Buffering agents as well as additives such as saline or glucose may be added to make the solutions isotonic. The compound also may be solubilized in alcohol/propylene glycol or polyethylene glycol for drip intravenous administration. The compositions also may be presented in unit dosage form in ampoules or in multidose containers, preferably with added preservative.

Alternatively, the active ingredients may be in powder form for reconstituting with a suitable vehicle prior to administration.

The term "unit dosage form" as used in the specification and claims refer to physically discrete units, each unit containing a predetermined quantity of active ingredient calculated to produce the desired therapeutic effect in association with the pharmaceutical carrier. Examples of such unit dosage forms are tablets, capsules, pills, powder packets, wafers, measured units in ampoules or in multidose containers and the like. A unit dosage of the present invention will generally contain from 10 to 200 milligrams of one of the compounds.

When the compound is for antifungal use any method of administration may be employed. For treating mycotic infections, oral administration is frequently preferred.

When the compound is to be employed for control of

Pneumocystis infections, it is desirable to directly treat lung and bronchi. For this reason inhalation methods are preferred. For administration by inhalation, the compounds of the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or nebulisers. The preferred delivery system for inhalation is a metered dose inhalation (MDI) aerosol which may be formulated as a suspension of Compound I in a suitable propellant such as fluorocarbon or hydrocarbons.

The following examples illustrate the preparation of Compound I and compositions of Compound I useful in the therapeutic application of Compound I, but are not to be constmed as limiting.

EXAMPLE 1

A solution of the starting material, Compound A (where R₂= p-ɸ-ɸ-ɸ-OC₅H_{1 1}-n), ethanolamine hydrochloride (36

equivalents), and 4.0M HCl in 1,4-dioxane (1 equivalent) in anhydrous dimethylsulfoxide is stirred at 25°C for a period of 2.5 days. HPLC analysis of the reaction mixture (RP-C18, CH₃CN/H₂O (0.1%

CF₃COOH), UV @ 210 and 277 nm) indicates conversion to a more polar product. The mixture is diluted five-fold with water. Preparative 5% step-gradient RP18-HPLC of this solution, eluting with

CH₃CN/H₂O (0.1 % CH₃COOH), is monitored by UV at 277nm. The product-containing fractions are combined and lyophilized to obtain the above aminoethyl ether as a mixed HCI/CH₃COOH salt. The mixed salt is dissolved in water and this solution is loaded onto a AG2-X8 (Cl-) ion-exchange column (BioRad). Elution with two column volumes of water and lyophilization of the eluate produces the product Compound la (SEQ. ID NO. 1) as the hydrochloride:

C₆₀H₇₈CIN₉O_{1 8}, mol. wt. = 1248.8.

EXAMPLE 2

In a similar manner, a solution in anhydrous dimethylsulfoxide of Compound A (where R₂=p,p'-ɸ-ɸ-OC₈H₁₇), ethanolamine hydrochloride (36 equivalents), and 4.0M HCI in 1 ,4- dioxane (1 equivalent), is stirred at 25°C for 2.5 days. When HPLC analysis of the reaction mixture (RP-C18, CH₃CN/H₂O (0.1 %

CF₃COOH), UV @ 210 and 277 nm) indicates conversion to a more polar product, the mixture is diluted five-fold with water. Preparative 5% step-gradient RP18-HPLC of this solution, eluting with CH₃CN/H₂O (0.1 percent acetic acid) is monitored by UV at 277 nm. The product containing fractions are combined and lyophilized to obtain the above Compound lb as a mixed HCI/CH₃COOH salt. The mixed salt is dissolved in water and the solution loaded onto a AG2-X8 (Cl-) ion- exchange column (BioRad) to obtain the hydrochloride salt. Elution with two column volumes of water and lyophilization of the eluate produces Compound lb (SEQ. ID NO. 1 ) as the hydrochloride salt:

C₅₇H₈₀CIN₉O_{1 8}, m.w. = 1214.8.

EXAMPLE 3

In an operation carried out in a manner similar to that described in Examples 1 and 2, Compound A (where R₂ is

excess ethanolamine hydrochloride (36 equivalents) and 4.0 M HCI in 1 ,4- dioxane, all in anhydrous dimethylsulfoxide are stirred together for about 2 1/2 days or until HPLC analysis indicates conversion to a more polar product. The resulting solution is diluted with water and preparative 5% step-gradient RP18-HPLC is carried out eluting with CH₃CN/H₂O (0.1 % CH₃COOH), and monitoring at 277 nm. The product-containing fraction are combined and lyophilized to obtain the aminoethyl ether as a mixed HCI/CH₃COOH salt. The mixed salt is converted to the hydrochloride salt using an ion-exchange column AG2-X8(Cl-) as previously described:

C₆₃H₉₀Cl₂N₁₀O_{1 8}, M.W. 1346.4.

EXAMPLE 4

In operations, carried out in a manner similar to the

preceding examples, Compound Id C₆₆H₁₀₀CI₃N_{1 1}O_{1 8}, m.w. 1442.0 is obtained.

EXAMPLE

In operations carried out in a manner similar to that described in the foregoing example, the following compounds are prepared:

EXAMPLE 13

1000 hard gelatin capsules, each containing 500 mg of compound of Example 1 are prepared from the following formulation:

Compound Grams

Compound of Example 1 500

Starch 250

Lactose 750

Talc 250

Calcium stearate 10

A uniform mixture of the ingredients is prepared by blending and used to fill two-piece hard gelatin capsules.

EXAMPLE 14

An aerosol composition may be prepared having the following formulation:

Per Canister

Compound of Example 1 24 mg

Lecithin NF Liquid

Concentrated 1.2 mg

Trichlorofluoromethane, NF 4.026 g

Dichlorodifluoromethane, NF 12.15 g EX AMPLE 15

1000 compressed tablets each containing

500 mg of compound of Example 2 are prepared from the following formulation:

Compound Grams

Compound of Example 2 500

Starch 750

Dibasic calcium phosphate, 5000

hydrous

Calcium stearate 2.5

The finely powdered ingredients are mixed well and granulated with 10 percent starch paste. The granulation is dried and compressed into tablets.

PREPARATION OF STARTING MATERIAL

The starting material Compound A may be obtained by first cultivating Z. arboricola ATCC 20868 in a nutrient medium enriched in mannitol as the primary source of carbon as described in U.S. Patent No. 5,021 ,341 , June 4, 1991 to obtain pneumocandin B₀. Pneumocandin B_o may be converted into Compound A by subjecting pneumocandin B_o in a nutrient medium to a deacylating enzyme until substantial deacylation occurs, said enzyme having first been obtained by cultivating a microorganism of the family Pseudomundaceae or Actinoplanaceae, as described in Experentia 34, 1670 (1978), U.S. 4,293,482 or EPA 0 451 957, October 16, 1991 , and thereafter recovering the deacylated cyclopeptide, and acylating the deacylated cyclopeptide by mixing together said cyclopeptide with an appropriate active ester R₂COX using conventional procedures to obtain Compound I with the desired acyl group.

The active esters R^ICOX may be prepared by methods known to the skilled chemist as illustrated in the following examples. Although any active ester is appropriate, the compounds are illustrated with pentafluorophenyl esters.

Preparation of Alkoxyterphenyl Side Chains

The terphenylcarboxylic acid esters may be prepared through the following sequence of reactions, illustrated with a specific example as follows:

A. Preparation of pentyloxy - substituted - terphenylcarboxylic acid:

Part A: 4-(4-n-Pentyloxyphenyl) bromobenzene.

To a stirred solution of 25.5g of 4-(4-bromophenyl)phenol (Compound (a)) in 400 mL of dimethylsulfoxide was added 40.9 mL of 2.5 N NaOH, followed by 12.7 mL of n-pentyl bromide, and the resulting mixture heated at 70°C for 18 hours to obtain in the mixture, compound (b). The mixture was partitioned between 1000 mL of ethyl acetate and 500 mL water and from the organic phase after washing with water and brine, and drying was obtained 30.9 grams of Compound (b) as a white solid.

¹ H NMR (400MHz, DMSO-d₆) δ 0.93 (t, J=7.2 Hz, 3H), 1.41 (m, 4H), 1.79 (m, 2H), 3.97 (t, J=6.6 Hz, 2H) 6.94 (d, J=8.8 Hz, 2H), 7.39 (d, J=8.6 Hz, 2H), 7.45 (d, J=8.8 Hz, 2H), 7.51 (d, J=8.6 Hz, 2H).

Part B: 4-(4-n-Pentyloxyphenyl)phenylboronic acid.

To a stirred suspension of 1.0 grams of Compound (b) in 20 mL anhydrous tetrahydrofuran at -78°C under a nitrogen atmosphere was added 1.32 mL of 2.5M n-butyl lithium in hexanes. After 15 minutes 0.760 mL of tri-isopropyl borate was added and the stirring continued at -78°C for 15 minutes and then at 25°C for 40 minutes. The mixture was acidified and partitioned between ether and water to obtain the boronic acid compound (c) in the reaction mixture. The compound was recovered by washing with water and brine and drying to obtain 750 mg of 4-(4-n-pentyloxyphenyl) phenylboronic acid as white solid with the following ¹H NMR. ¹H NMR (400MHz, DMSO-d₆) δ 0.89 (t, J=7.2 Hz, 3H), 1.38 (m, 4H), 1.72 (m, 2H), 3.99 (t, J=6.5 Hz, 2H) 6.99 (d, J=8.8 Hz, 2H), 7.57 (d, J=8.2 Hz, 2H), 7.60 (d, J=8.8 Hz, 2H), 7.83 (d, J=8.2 Hz, 2H) Part C: Pentafluorophenyl 4"-(n-pentyloxy)-[1 ,1':4',1"-terphenyl]-4- carboxylate

To a stirred mixture of 1.0 g of the boronic acid and 0.0874 mL of 4-iodobenzoic acid in 11 mL ethanol and 30 mL toluene was added 5.3 mL of a 2M aqueous solution of sodium carbonate followed by 204 mg tetrakis(triphenylphosphine)palladium and the reaction mixture heated under reflux (100°C) for 18 hours. Thereafter, the mixture was cooled, acidified and partitioned between ethyl acetate and water. The organic phase was washed with water and brine and dried, then filtered through a bed of celite to obtain after removal of solvent and purification with flash silica gel chromatography to obtain 4"-(n-pentyloxy)-[1,1':4',1 "-terphenyl]-4-carboxylic acid. ¹H NMR (400MHz, DMSO-d₆) δ 0.89 (t, 3H), 1.37 (m, 4H), 1.72 (m, 2H), 3.98 (t, 2H) 7.01 (d, 2H).

To a mixture of 4"-(n-pentyloxy)-[1,1':4',1 "-terphenyl]-4-carboxylic acid (10.5 mmol) and dicyclohexylcarbodiimide (10.5 mmol) in ethyl acetate at 0°C is added pentafluorophenol (11.5 mmol). The mixture is stirred at 25°C for a period of 18 h, producing a precipitate. The mixture is filtered. The filtrate is washed with water and brine and dried with magnesium sulfate. The solvent is removed in vacuo to obtain pentafluorophenyl 4"-(n-pentyloxy)-[1 ,1':4',1 "-terphenyl]-4-carboxylate, C₃₀H₂₃F₅O₃, M.W.= 526.5.

Preparation of Alkoxy Biphenyl Side Chains.

The biphenylcarboxylic acid esters may be obtained through the following sequence of reactions illustrated as follows: A. Preparation of Octyloxybiphenylcarboxylic acid

n-Octyl bromide (0.102 mol) is added to a solution of 4-(4-hydroxyphenyl)benzoic acid (0.102 mol) and 2.5N sodium hydroxide (0.102 mol) and the mixture stirred at 70°C for a period of 18 hours. The reaction mixture is allowed to cool and then acidified to pH 3 and

partitioned between ethyl acetate and water. The organic phase is washed with water and brine and the solvent then removed to obtain the 4'-n-octyloxy[1 ,1 '-biphenyl]-4-ylcarboxylic acid, C₂₁H₂₃O₃, M.W. 326.4 B. Preparation of pentafluorophenyl Ester

Pentafluorophenol (1 1.5 mmol) is added at 0° to a mixture of 10.5 mmol 4'-n-octyloxy[1 ,1 '-biphenyl]-4-ylcarboxylic acid and 10.5 mmol of dicyclohexylcarbodiimide in ethyl acetate. The mixture is stirred at 25°C for a period of 18 hours whereupon a precipitate is formed. The reaction mixture is filtered, the filtrate washed with water and brine and dried, the solvent removed in vacuo to obtain pentafluorophenyl 4'-n-octyloxy[1 ,1'-biphenyl]-4-ylcarboxylate, C₂₇H₂₅F₅O₃, M.W. 492.5. Preparation of AminoethyloxyBiphenyl Side chains

Preparation of 4'-(2-[4-Cyclohexylmethylpiperidin-1-yl]ethoxy)-[ 1 ,1 '-biphenyl]-4-ylcarboxylic acid, Pentafluorophenyl Ester

Part A: Preparation of 4-Cyclohexylmethylpiperidine

4-Benzylpiperidine is dissolved in glacial acetic acid containing PtO₂ (approximately 50 wt percent). A Paar hydrogenator is used and the reaction vessel is flushed with H₂ and pressurized to 3 atm. The mixture is shaken for sufficient time to give reduction of the aromatic ring to the fully saturated product which is determined by the uptake of 3 molar equivalents of H₂. The black solid is filtered and the acetic acid removed by evaporation under reduced pressure to obtain the product as an acetate salt.

Part B: Preparation of 1 -(2-Hydroxyethyl)-4-cyclohexylmethyl- piperidine

The product from Part A (1.0 eq) is dissolved in dichloromethane containing an equimolar amount of diisopropylethyl amine.

Ethylene oxide (10 eq) is added and the mixture is stirred until starting material is consumed. The desired product is obtained by removal of the solvent in vacuo followed by purification by column chromatography. Part C: Preparation of 4'-(2-[4-cyclohexylmethylpiperidine-1 - yl]ethoxy)-[ 1 ,1 '-biphenyl]-4-ylcarboxylic acid

4'-Hydroxy-[1 ,1'-biphenyl-4-ylcarboxylic acid methyl ester (1.0 eq) is dissolved in dichloromethane and triphenylphosphine (1.3 eq) and the hydroxyethyl compound (1.0 eq) from Part B is added. Next, diethyl azodicarboxylate (1.3 eq) is added and the mixture is stirred until starting material is consumed. The mixture is diluted with dichloromethane and washed with water. The organic layer is dried with MgSO₄ and filtered. The solvent is removed in vacuo and the residue is dissolved in ethanol. An excess of 3N sodium hydroxide is added and the mixture stirred for several hours. The reaction is neutralized with 2N HCI and is extracted with ethyl acetate. The ethyl acetate layer is dried with MgSO₄ , filtered and the solvent vaporized under reduced pressure. The desired product is obtained in substantially pure form by column chromatography.

Part D: Preparation of the Pentafluorophenyl Ester

The carboxylic acid (1.0 eq) and dicyclohexylcarbodiimide (1.0 eq) are dissolved in ethyl acetate and the solution is cooled to 0°C. Pentafluorophenol (1.05 eq) is added, the ice bath then is removed and the reaction stirred at ambient temperature for 18-24 h. An equal volume of ether is added, the mixture is filtered and the solvent removed in vacuo. The product (MW = 587.64) may be obtained in a sufficiently pure form to be utilized "as is" for nucleus acylation.

Preparation of 4'-(2-[4-Undecylpiperizin-1 -yl]-ethoxy)[1 ,1 '-biphenyl]-4-ylcarboxylic acid, Pentafluorophenyl Ester

Part A: Preparation of 4-Undecylpiperazine

Excess piperazine (5 eq) and 1 -bromoundecane (1.0 eq) are dissolved in dichloromethane and allowed to react ovemight. The mixture is extracted with aqueous sodium bicarbonate and the organic layer dried with sodium sulfate. The mixture is filtered, the solvent removed in vacuo and the residue purified by column chromatography.

Part B: Preparation of 1 -(2-Hydroxyethyl)-4-undecylpiperazine

The substituted piperazine above (1.0 eq) is dissolved in n-propanol and bromoethanol (1.0 eq) is added along with diisopropylethyl amine (1.1 eq). After several hours, the solvent is removed in vacuo and the residue dissolved in dichloromethane. The organic layer is washed with water and then aqueous sodium bicarbonate. The organic layer is dried with MgSO₄ and filtered. Removal of the solvent in vacuo is followed by purification by column chromatography.

Part C: Preparation of the Carboxylic Acid

The procedure is essentially the same as describe in Part C above except that the hydroxyethyl piperazine from above is substituted for the

hydroxyethyl piperidine.

Part D: Preparation of the Pentafluorophenyl Ester

The procedure is identical to Part D from above except that piperazinyl-substituted-biphenyl carboxylic acid is used. The product (MW = 646.75) may be obtained in a sufficiently pure form to be utilized "as is" in nucleus acylation. SEQUENCE LISTING

(1) GENERAL INFORMATION

(i) APPLICANTS: BALKOVEC, JAMES M.

BOUFFARD, FRANCES, A.

DROPINSKI, JAMES F.

(ii) TITLE OF INVENTION: CYCLOHEXYLPEPTIDYL AMINOALKYL ETHERS (iii) NUMBER OF SEQUENCES: 1

(iv) CORRESPONDENCE ADDRESS:

(A) ADDRESSEE: ELLIOT KORSEN

(B) STREET: P.O. BOX 2000, 126 EAST LINCOLN AVE.

(C) CITY: RAHWAY

(D) STATE: NEW JERSEY

(E) COUNTRY: USA

(F) ZIP: 07065

(v) COMPUTER READABLE FORM:

(A) MEDIUM TYPE: Floppy Disk

(B) COMPUTER: Macintosh Ilci

(C) OPERATING SYSTEM: System 7.0.1

(D) SOFTWARE: Micrsoft Word 5.1a

(vi) CURRENT APPLICATION DATE:

(A) APPLICATION NUMBER:

(B) FILING DATE: 25-APR-1994

(C) CLASSIFICATION:

(vii) PRIOR APPLICATION DATA: NONE

(A) APPLICATION NUMBER:

(B) FILING DATE:

(viii) ATTORNEY/AGENT INFORMATION:

(A) NAME: E. KORSEN

(B) REGISTRATION NUMBER: 32,705

(C) REFERENCE/DOCKET NUMBER: 18980P

(ix) TELECOMMUNICATION INFORMATION

(A) TELEPHONE: 908-594-5493

(B) TELEFAX: 908-594-4720

(C) TELEX:

(2) INFORMATION FOR SEQ ID NO: 1

(i) SEQUENCE CHARACTERISTICS:

(A) LENGTH: 6

(B) TYPE: AMINO ACID

(C) STRANDEDNESS : NA

(D) TOPOLOGY: CIRCULAR

(ii) MOLECULE TYPE:

(A) DESCRIPTION: PEPTIDE

(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1

Xaa Thr Xaa Xaa Xaa Xaa

1 5

Claims

WHAT IS CLAIMED IS:

1. A compound having the formula (SEQ ID NO 1)

wherein:

R₁ is -CH₂CH(NH₂)CH₂R^I

-CnH₂nNR^IIR^III

-(CH₂)_{1 -3}CH(NH₂)R^IV or

-C_nH₂nNHR^V

wherein n is 2 to 6;

R₂ is

wherein

R^a is C₁-C₁₀ alkyl; or (CH₂)_qNR^bR^c wherein

R^b and R^c are independently

H, C₁ -C₁₀ alkyl or

R^b and R^c taken together are or

wherein R^d is C₁ -C_{1 6} alkyl,

phenyl or benzyl;

R^I is -OH

-NH₂

-NHC(=NH)NH₂

-NHC(=NH)(CH₂)_0-3H R^II is -H

-C₁ -C₄ alkyl or

-benzyl R^III is -H

-C₁-C₄ alkyl

-benzyl or

R^II and R^III together are -(CH₂)₄- or -(CH₂)₅- R^IV is -C₁ -C₄ alkyl

-CONH₂

RV is -C(=NH)NH₂

-C(=NH)(CH₂)_0-3H

-(CH₂)_2-4NH₂

-(CH₂)_2-4OH

-CO(CH₂)_{1 -3}NH₂ -(CH₂)_2-4NH(C=NH)NH₂

-(CH₂)_2-4NH(C=NH)(CH₂)_0-3H or

p is an integer from 1 to 2, inclusive and

q is an integer from 2 to 4, inclusive and pharmaceutically acceptable salts thereof.

2. A compound according to Claim 1 having the formula

3. A compound according to Claim 1 having the formula

A compound according to Claim 1 having the formula

5. A compound according to Claim 1 having the formula

6 An antibiotic composition comprising an antimicrobial amount of a compound of Claim 1 in a pharmaceutically acceptable carrier.

7. A composition according to Claim 6 in unit dosage form wherein the compound of Claim 1 is present in an amount of 10 mg to 200 milligrams.

8. A method for treating mycotic infections comprising administering a therapeutic amount of a compound of Claim 1 to a subject in need of therapy.

9. A method for treating Pneumocystic carinii

infections which comprises administering a therapeutic amount of the compound of Claim 1.

10. A method for reducing the cysts formed in the lungs of immune compromised patients infected with Pneumocystis carinii which comprises administering an effective amount of the compound of Claim 1.