FIELD OF THE INVENTION The present invention relates to the treatment or prevention of non-invasive fungus-induced mucositis with cyclohexapeptide antifungal agents, in particular, echinocandins.

BACKGROUND OF THE INVENTION Mayo Clinic researchers recently discovered that an immune system response to fungus may be responsible for inflammations of mucosal tissues in patients suffering from chronic rhinosinusitis, chronic otitis media, chronic colitis, asthma, and Crohn's disease. See, i. e., Ponikau, J., et al.,"The Diagnosis and Incidence of Allergic Fungal Sinusitis,"Mayo Clinic Proceedings, 74, 877-884 (1999) ; and WO 99/020261 entitled"Methods and Materials for Treating and Preventing Inflammation of Mucosal Tissue"filed by Jens Ponikau and published on April 29, 1999. According to the Mayo Clinic, an estimated 37 million people in the United States suffer from chronic sinusitis, an inflammation of the membranes of the nose and sinus cavity. In a prospective study, fungal cultures of nasal secretions were positive in 202 (96%) of 210 consecutive chronic rhinosinusitis (CRS) patients. Eosinophils were found in the allergic mucin of

the majority of the patients diagnosed with allergic fungal sinusitis (AFS) ; however, no evidence of immunoglobulin E- mediated hypersensitivity to fungal allergens was found in the majority of AFS patients. Based on the foregoing, Mayo concluded that fungi residing in the mucus was triggering an immune response which in turn causes an inflammation of mucosal tissue and thus proposed a treatment regime whereby an antifungal agent is mucoadministered to the affected area. In WO 99/020261, a variety of antifungal agents are listed as being useful for this indication ; however, none of the classes listed include cyclohexapeptides, nor are any of the known echinocandin compounds included in the specific list of compounds.

SUMMARY OF THE INVENTION The present invention provides a method for treating a non-invasive fungus-induced mucositis in a mammal in need thereof comprising the step of contacting an echinocandin compound with fungi residing in the mucus of said mammal.

The method is particularly useful for the treatment of non- invasive fungus-induced chronic rhinosinusitis, chronic asthma symptoms, chronic otitis media, chronic colitis and Crohn's disease.

In another embodiment of the invention, a method is provided for preventing non-invasive fungus-induced mucositis in a mammal by mucoadministrating an echinocandin such that it contacts mucus in an amount, at a frequency, and for a duration effective to prevent non-invasive fungus- induced mucositis (e. g., non-invasive fungus-induced chronic rhinosinusitis, chronic asthma symptoms, chronic otitis media, chronic colitis and Crohn's disease).

In yet another embodiment of the present invention, a medicament is provided for the treatment or prevention of non-invasive fungus-induced mucositis comprising an echinocandin.

Definitions The term"mucositis"refers to an inflammation, as opposed to an infection, of a mucus membrane.

The term"echinocandin"refers to a compound having the following general structure : wherein : R is an alkyl group, an alkenyl group, an alkynyl group, an aryl group, heteroaryl group, or combinations thereof ; R1, R3, R6, R7, and Rio are independently hydroxy or hydrogen ; R2 is hydroxy, aminoalkylamine (e. g., -NHCH2CH2NH2), or hydrogen ; R4 is hydrogen, methyl or alkylamido (e. g.,-CH2C (O) NH2) ; R5 is alkylamine (e. g.,-CH2CH2NH2), alkylamido (e. g., -CH2C (O) NH2), methyl or hydrogen ;

R8 is-OH,-OS03H,-OP03H2,-OP03HRa, or-OP02HR, where Ra is hydroxy, C1-C6 alkyl, C1-C6 alkoxy, phenyl, phenoxy, p-halophenyl, p-halophenoxy, p-nitrophenyl, p-nitrophenoxy, benzyl, benzyloxy, p-halobenzyl, p-halobenzyloxy, p- nitrobenzyl, or p-nitrobenzyloxy ; Rg is-H,-OH, or-OS03H ; RI, is methyl or hydrogen ; and pharmaceutically acceptable salts, solvates, hydrates, or prodrugs thereof. Even though a specific chiral form is depicted above, other chiral forms are within the spirit and scope of the present invention. Examples of compounds encompassed by the term"echinocandin"specifically include all of the compounds described in U. S. Patent Nos.

4, 293, 489 ; 5, 965, 525 ; US 5, 693, 750 ; 5, 569, 646 ; 5, 502, 033 ; 5, 792, 746 ; 5, 378, 804 ; 5, 854, 213 ; 5, 684, 128 ; 5, 646, 245 ; 5, 516, 757 ; 5, 514, 650 ; 5, 386, 009 ; 5, 378, 804 ; 5, 310, 726 ; 5, 166, 135 ; 5, 159, 059 ; 5, 049, 546 ; and 4, 931, 352, all of which are incorporated herein by reference. Further examples of compounds encompassed by the term"echinocandin"also include those compounds described in PCT applications WO 98/23637 and WO 96/11210 ; and EP application EP 788511.

"Echinocandin B"or"ECB"refers to an echinocandin compound as described above where R1, R2, R3, R6, R7, R8 and Rio are hydroxy groups ; R4, R5 and Rll are methyl groups ; R9 is a hydrogen. In the natural product, R is a linoleoyl group. In a particularly useful semi-synthetic derivative, R has both a rigid and a flexible component, for example where R is represented by the following formula

The preparation of the terphenylpentoxy semisynthetic derivative (also known as LY303366) is described in U. S.

Patent No. 5, 965, 525 and exemplified in the Examples.

The term"Caspofungin"or"MK-991"refers to an echinocandin compound as described above where R1, R3, R6, R7, R8 and Rio are hydroxy groups ; R2 is-NHCH2CH2NH2 ; R4 and Rn are methyl groups ; R5 is-CH2CH2NH2 ; Rg is a hydrogen and R is- (CH2) 8CH (CH3) CH2CH (CH3) CH2CH3. Preparation of Caspofungin and other useful derivatives may be found in U. S. Patent Nos. 5, 792, 746 and 5, 378, 804, each of which are incorporated herein by reference.

The term"FR-901379"refers to an echinocandin compound as described above where R1, R2, R3, R6, R7, R8 and Rio are hydroxy groups ; R4 and Rll are methyl groups ; R5 is -CH2C (O) NH2 ; Rg is a-OS03-Na+ and R is-(CH2) 14CH3. The preparation of FR-901379 and its derivatives may be found in U. S. Patent Nos. US 5, 693, 750 ; 5, 569, 646 ; and 5, 502, 033, all of which are incorporated herein by reference.

The term"FK-463"refers to an echinocandin compound as described above where R1, R2, R3, R6, R7, R8 and Rio are hydroxy groups ; R4 and Rll are methyl groups ; R5 is -CH2C (O) NH2 ; Rg is a-OS03-Na+ and R is represented by the following structure : The preparation of FK-463 and its derivatives may be found in PCT applications WO 98/23637 and WO 96/11210 ; and EP application EP 788511.

The term"alkyl"refers to a hydrocarbon radical of the general formula CnH2n1 containing from 1 to 30 carbon atoms

unless otherwise indicated. The alkane radical may be straight, branched, cyclic, or multi-cyclic. The alkane radical may be substituted or unsubstituted. Similarly, the alkyl portion of an alkoxy group or alkanoate have the same definition as above.

The term"alkenyl"refers to an acyclic hydrocarbon containing at least one carbon-carbon double bond. The alkene radical may be straight, branched, cyclic, or multi- cyclic. The alkene radical may be substituted or unsubstituted.

The term"alkynyl"refers to an acyclic hydrocarbon containing at least one carbon carbon triple bond. The alkyne radical may be straight, or branched. The alkyne radical may be substituted or unsubstituted.

The term"aryl"refers to aromatic moieties having single (e. g., phenyl) or fused ring systems (e. g., naphthalene, anthracene, phenanthrene, etc.). The aryl groups may be substituted or unsubstituted. Substituted aryl groups include a chain of aromatic moieties (e. g., biphenyl, terphenyl, phenylnaphthalyl, etc.) The term"heteroaryl"refers to aromatic moieties containing at least one heteratom within the aromatic ring system (e. g., pyrrole, pyridine, indole, thiophene, furan, benzofuran, imidazole, pyrimidine, purine, benzimidazole, quinoline, etc.). The aromatic moiety may consist of a single or fused ring system. The heteroaryl groups may be substituted or unsubstituted.

Within the field of organic chemistry and particularly within the field of organic biochemistry, it is widely understood that significant substitution of compounds is tolerated or even useful. In the present invention, for example, the term alkyl group allows for substituents which

is a classic alkyl, such as methyl, ethyl, isopropyl, isobutyl, tertiary butyl, hexyl, isooctyl, dodecyl, stearyl, etc. The term group specifically envisions and allows for substitutions on alkyls which are common in the art, such as hydroxy, halogen, alkoxy, carbonyl, keto, ester, carbamato, etc., as well as including the unsubstituted alkyl moiety.

However, it is generally understood by those skilled in the art that the substituents should be selected so as to not adversely affect the pharmacological characteristics of the compound or adversely interfere with the use of the medicament. Suitable substituents for any of the groups defined above include alkyl, alkenyl, alkynyl, aryl, halo, hydroxy, alkoxy, aryloxy, mercapto, alkylthio, arylthio, mono-and di-alkyl amino, quaternary ammonium salts, aminoalkoxy, hydroxyalkylamino, aminoalkylthio, carbamyl, carbonyl, carboxy, glycolyl, glycyl, hydrazino, guanyl, and combinations thereof.

DETAILED DESCRIPTION Evidence exists to support the theory that at least a subset of diseases diagnosed as chronic rhinosinusitis (CRS), asthma and irritable bowel syndrome is caused by colonization of the mucus membranes by a variety of species of fungi which in some populations triggers an inappropriate and massive eosinophil infiltration of the surrounding mucosa and tissue. (See, i. e., Ponikau, J., et al.,"The Diagnosis and Incidence of Allergic Fungal Sinusitis,"Mayo Clinic Proceedings, 74, 877-884 (1999) ; WO 99/020261 entitled"Methods and Materials for Treating and Preventing Inflammation of Mucosal Tissue"filed by Jens Ponikau and published on April 29, 1999 ; and references cited therein) In WO/020261, treatment with the antifungal agents

amphotericin B and intraconazole has been shown to treat this inappropriate immune response by reducing the burden of the triggering fungal organisms. The use of the echinocandin antifungal agents, such as LY303366, MK-991 and FR-901379 and related compounds are potent inhibitors of cell wall biosynthesis in fungi. Unlike current existing antifungal agents, such as amphotericin B and itraconazole, the echinocandins have broader spectrum, greater potency and better toxicological properties. In addition, echinocandins are active against azole resistant fungal organisms. Based on the foregoing observations, the echinocandins provide a unique set of antifungal agents for treatment or prevention of non-invasive fungus-induced mucositis.

The cyclic peptides used in the present invention may be produced by culturing various microorganisms. Suitable natural product starting materials belonging to the echinocandin cyclic peptide family include Echinocandin B, Echinocandin C, Echinocandin D, Aculeacin Ay, Mulundocandin, Sporiofungin A, Pneumocandin Ao, WF11899A, and Pneumocandin Bo. In general, the cyclic peptides may be characterized as a cyclic hexapeptide nucleus with an acylated amino group on one of the amino acids. The amino group on the naturally- occurring cyclic peptide is typically acylated with a fatty acid group forming a side chain off the nucleus. Examples of naturally-occurring acyl groups include linoleoyl (Echinocandin B, C and D), palmitoyl (Aculeacin Ay and WF11899A), stearoyl, 12-methylmyristoyl (Mulundocandin), 10, 12-dimethylmyristoyl (Sporiofungin A and Pneumocandin Ao) and the like.

Semi-synthetic derivatives may be prepared by removing the fatty acid side chain from the cyclic peptide nucleus to produce a free amino group (i. e., no pendant acyl group

-C (O) R). For example, the fatty acid side chain may be removed using an echinocandin B-deacylase isolated from Actinoplanes Utahensis. The free amine is then reacylated with a suitable acyl group using conventional acylation chemistry well-known to those skilled in the art. For example, the echinocandin B nucleus has been re-acylated with certain nonnaturally occurring side chain moieties to provide a number of antifungal agents. In addition, the various free hydroxyl groups pendant to the peptide units of the core ring may be modified to enhance activity. and/or solubility. See, e. g., European Patent Applications EP 943, 623 and EP 906, 915 ; and U. S. Patent Nos. 4, 293, 489 ; 5, 629, 290 ; 5, 786, 325 ; 5, 693, 611 ; 5, 618, 787 ; 5, 646, 111 ; 5, 932, 543 ; and 5, 965, 525, each of which are incorporated herein by reference.

Those skilled in the art will appreciate that the N- acyl side chain encompasses a variety of side chain moieties known in the art. Suitable side chain moieties include substituted and unsubstituted alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups and combinations thereof. Preferably, the side chain contains both a linearly rigid section and a flexible alkyl section to maximize antifungal potency. Compounds having a side chain containing both a rigid and flexible section are described in U. S. Patent No. 5, 965, 525, incorporated herein by reference. Representative examples of preferred acyl side chains include R groups having the following structures :

where A, B, C and D are independently hydrogen, Cl-Cl2 alkyl, C2-C12 alkynyl, Cl-Cl2 alkoxy, Cl-Cl2 alkylthio, halo, or -0- (CH2)m-[O-(CH2)n]p-O-(C1-C12 alkyl) or -O-(CH2) q-X-E ; m is 2, 3 or 4 ; n is 2, 3 or 4 ; p is 0 or 1 ; q is 2, 3 or 4 ; X is pyrrolidino, piperidino or piperazino ; and E is hydrogen, Cl-C12 alkyl, C3-C12 cycloalkyl, benzyl or C3-C12 cycloalkylmethyl.

Other echinocandin compounds have also been shown to be useful antifungal agents, such as MK-991, FR-901379, and FK- 463. MK-991 and related derivatives are described in U. S.

Patent Nos. 5, 792, 746 ; 5, 378, 804 ; 5, 854, 213 ; 5, 684, 128 ; 5, 646, 245 ; 5, 516, 757 ; 5, 514, 650 ; 5, 386, 009 ; 5, 378, 804 ; 5, 310, 726 ; 5, 166, 135 ; 5, 159, 059 ; 5, 049, 546 ; and 4, 931, 352, all of which are incorporated herein by reference. FR- 901379 and related derivatives are described in U. S. Patent Nos. US 5, 693, 750 ; 5, 569, 646 ; and 5, 502, 033, all of which are incorporated herein by reference. FK-463 and its derivatives may be found in PCT applications WO 98/23637 and WO 96/11210 ; and European application EP 788511.

As noted above, the cyclic peptides described herein may be prepared by fermentation of known microorganisms as described in the art. The subsequent deacylation is typically carried out enzymatically using a deacylase enzyme by known materials and procedures described in the art.

For example, U. S. Patent No. 3, 293, 482 (Abbott et al.), incorporated herein by reference, describes the deacylation and preparation of the cyclic peptide of formula I where R4, R5, and RI, are methyl, Rg is hydrogen, and R1, R2, R3, R6, R7, R8 and Rlo are each hydroxy. U. S. Patent No. 4, 299, 763 (Abbott et al.), incorporated herein by reference, describes the deacylation and preparation of the cyclic peptide of formula I where R4, R5, and RI, are methyl, R2 is hydroxy, R7 and Rg are hydrogen and R1, R3, R6, R8 and Rio are each hydroxy. U. S. Patent No. 3, 978, 210 (Mizuno et al.), incorporated herein by reference, describes the preparation of aculeacin. U. S. Patent No. 4, 304, 716, incorporated herein by reference, describes the deacylation and preparation of the cyclic peptide of formula I where R5 is -CH2C (O) NH2 ; Rll is methyl ; R4 and Rg are hydrogen ; R1, R2, R3, R6, R7, R8 and Rio are each hydroxy and the acyl group with substituent R is myristoyl.

Cyclic peptides where R2 and R7 are each hydrogen may be prepared by subjecting the corresponding compound (where R2 and R7 are each hydroxy ; the ornithine alpha-amino group may be a free amino group or acylated) to a strong acid and a reducing agent at a temperature of between-5°C and 70°C, in a suitable solvent. Suitable strong acids include trichloroacetic acid, trifluoroacetic acid or boron trifluoride etherate. A preferred strong acid is trifluoroacetic acid. Suitable reducing agents include sodium cyanoborohydride or triethylsilane. A preferred reducing agent is triethylsilane. Suitable solvents include methylene chloride, chloroform or acetic acid, preferably methylene chloride. The strong acid is present in an amount from about 2 to 60 mol per mol of substrate, and the reducing agent is present in an amount from about 2 to 60

mol per mol of substrate. The acid reduction process selectively removes the aminal (R2) and benzylic (R7) hydroxy groups.

Acylation of the a-amino group on the ornithine unit may be accomplished in a variety of ways well known to those skilled in the art. For example, the amino group may be acylated by reaction with an appropriately substituted acyl halide, preferably in the presence of an acid scavenger such as a tertiary amine (e. g., triethylamine). The reaction is typically carried out at a temperature between about-20°C to 25°C. Suitable reaction solvents include polar aprotic solvents, such as dioxane or dimethylformamide. Solvent choice is not critical so long as the solvent employed is inert to the ongoing reaction and the reactants are sufficiently solubilized to effect the desired reaction.

The amino group may also be acylated by reaction with an appropriately substituted carboxylic acid, in the presence of a coupling agent. Suitable coupling agents include dicyclohexylcarbodiimide (DCC), N, N'- carbonyldiimidazole, bis (2-oxo-3-oxazolidinyl) phosphinic chloride (BOP-Cl), N-ethoxycarbonyl-2-ethoxy-1, 2- dihydroquinoline (EEDQ), benzotriazole-1-yloxy- tripyrrolidinophosphonium hexafluorophosphate (PyBOP) and the like.

Alternately, the amino group may be acylated with an activated ester of a carboxylic acid such as p-nitrophenyl, 2, 4, 5-trichlorophenyl, hydroxybenzotriazole hydrate (HOBTH2O), pentafluorophenol, and N-hydroxysuccinimide carboxylate esters. Preferred acylating moieties are the 2, 4, 5-trichlorophenyl and HOBT carboxylate esters. The reaction is typically ran 1 to 65 hours at a temperature from about 0°C to 30°C in an aprotic solvent. The reaction

is generally complete after about 24 to 48 hours when carried out at a temperature between about 15°C to 30°C.

Suitable solvents include tetrahydrofuran and dimethylformamide or mixtures thereof. The amino group is generally present in equimolar proportions relative to the activated ester or with a slight excess of the amino group.

' !' The R-COOH precursor acids are prepared by hydrolyzing ß nitrile of the formula R-CN or an ester of the formula R- COO (C1-C4 alkyl). The nitrile and ester intermediates may be prepared using procedures known in the art. For example, the nitrile and ester intermediates where R is an alkoxy aryl moiety may be prepared using Procedure A or Procedure B, described below.

Procedure A One equivalent of an alkyl bromide, iodide, or p-toluenesulfonate is added to a mixture containing one equivalent of a base, such as potassium t-butoxid or potassium carbonate (K2CO3), and one equivalent of an hydroxy aryl compound in 200-300ml of acetonitrile (CH3CN).

The reaction mixture is refluxed for 6h and then concentrated in vacuo to provide a residue which is dissolved in a Et20/2N NaOH mixture. The resulting layers are separated and the organic layer is dried over magnesium sulfate (MgSO4), filtered and dried to provide the alkoxy aryl product.

Procedure B Diethylazodicarboxylate (1 equiv.) is added dropwise to a mixture containing an hydroxy aryl compound (1 equiv.), an alkyl alcohol (1 equiv.) and triphenylphosphine (1 equiv.) in 200-300ml of THF. After 17h, the solvent is removed in vacuo to provide a residue which is dissolved in Et2O.

The resulting mixture is washed with a 2N NaOH solution,

dried over MgSO4, filtered and concentrated to provide a product which is then crystallized from a Et2O/pentane mixture or, if the product contains a tertiary amine, the hydrochloride salt is formed and crystallized from a methanol (MeOH)/EtOAc mixture.

The nitrile and ester intermediates where R is an alkynyl aryl moiety may be prepared using Procedure C, below.

Procedure C A mixture containing Et20 (2 equiv.), palladium dichloride (0. 05 equiv.), triphenylphosphine (0. 1 equiv.), cuprous iodide (0. 025 equiv.) and an alkyne (1 equiv.) is added to one equivalent of an aryl bromide, iodide, or trifluoromethanesulfonate in CH3CN (600ml/0. 1mol of aryl reactant), under nitrogen (N2). The resulting mixture is refluxed for 17h and then the solvent is removed in vacuo to provide a residue which is slurried in 300 ml of Et20 and then filtered. The filtrate is washed with a IN HC1 solution, dried over MgSO4, filtered and then dried to provide the product.

The ester intermediates where R is a terphenyl moiety may be prepared using Procedure D, below.

Procedure D 1. Formation of boronic acid reactant Butyl lithium (1. 2 equivalents) is added to one equivalent of a cold (-78°C) aryl halide in THF. After 15 minutes, triisopropyl borate (2 equiv.) is added. After 10 minutes, the reaction mixture is warmed to room temperature and quenched by the addition of water (H2O), followed by the addition of IN HC1. The resulting layers are separated and

the organic layer is concentrated in vacuo to provide a solid which is collected by filtration and washed with hexane.

2. Formation of terphenyl ester Tetrakis (triphenylphosphine) palladium (0. 03 equiv.) is added to a mixture containing an aryl boronic acid (1 equiv.), K2CO3 (1. 5 equiv.) and methyl 4-iodobenzoate (1 equiv.) (or trichlorophenyl ester of iodobenzoate) in N2- purged toluene. The reaction mixture is refluxed for 7h and then decanted to remove the K2CO3 and dried in vacuo to provide a residue. This residue is triturated in CH3CN and filtered to provide the product.

The aryl nitriles and esters described above may be converted to the corresponding carboxylic acids by hydrolysis using Procedure E or Procedure F, below.

Procedure E An aryl nitrile is dissolved in ethanol (EtOH) and an excess of 50% NaOH solution and refluxed for 2h. Water is added to the reaction mixture until a solid precipitates.

This solid is collected by filtration, added to a dioxane/6N HC1 mixture and the resulting mixture is refluxed for 17h.

When the reaction is substantially complete, the carboxylic acid product is crystallized by the addition of H2O and then collected by filtration and dried in vacuo.

Procedure F An excess of 2N NaOH is added to an aryl ester in MeOH, and the resulting solution is refluxed for 5h and then acidified by the addition of excess HC1. Water is added to the reaction mixture until a solid (carboxylic acid)

precipitates. The carboxylic acid is collected by filtration and dried in vacuo.

The carboxylic acids may be converted to the corresponding 2, 4, 5-trichlorophenyl esters using Procedure G, below. The activated esters are then used to acylate the amino nucleus.

Procedure G A mixture containing an aryl carboxylic acid (1 equiv.), 2, 4, 5-trichlorophenol (1 equiv.) and DCC (1 equiv.) in CH2Cl2 is stirred for 17h and then filtered. The filtrate is concentrated to provide a residue which is dissolved in Et2O, filtered, and then pentane is added until crystallization begins. The crystals are collected by filtration and dried in vacuo.

Alternatively, the carboxylic acid may be activated by conversion to the corresponding hydroxybenzotriazole ester using Procedure H, below.

Procedure H An aryl carboxylic acid (1 equiv.) and a slight excess of N-mesylate substituted hydroxybenzotriazole (1. 2 equiv.) were reacted in the presence of a slight excess of a base such as triethylamine (Et3N) (1. 3 equiv.) in DMF, under N2.

When the reaction was complete, the mixture was diluted with toluene and washed with H2O. The organic portion was diluted with H20 and then filtered using t-butyl methyl ether (MTBE) for transferring the material. The resultant solid was washed with MTBE and then dried in vacuo.

The echinocandin compound may be isolated and used per se or in the form of its pharmaceutically acceptable salt, solvate and/or hydrate. The term"pharmaceutically acceptable salt"refers to non-toxic acid addition salts

derived from inorganic and organic acids. Suitable salt derivatives include halides, thiocyanates, sulfates, bisulfates, sulfites, bisulfites, arylsulfonates, alkylsulfates, phosphonates, monohydrogen-phosphates, dihydrogenphosphates, metaphosphates, pyrophosphonates, alkanoates, cycloalkylalkanoates, arylalkonates, adipates, alginates, aspartates, benzoates, fumarates, glucoheptanoates, glycerophosphates, lactates, maleates, nicotinates, oxalates, palmitates, pectinates, picrates, pivalates, succinates, tartarates, citrates, camphorates, camphorsulfonates, digluconates, trifluoroacetates, and the like.

A typical solution formulation is prepared by mixing the echinocandin and a carrier, diluent or excipient.

Suitable carriers, diluents and excipients are well known to those skilled in the art and include materials such as carbohydrates, waxes, water soluble and/or swellable polymers, hydrophilic or hydrophobic materials, gelatin, oils, solvents, water, and the like. The particular carrier, diluent or excipient used will depend upon the means and purpose for which the active ingredient is being applied. Solvents are generally selected based on solvents recognized by persons in the art as safe (GRAS) to be administered to a mammal. In general, safe solvents are non-toxic aqueous solvents such as, water and other non- toxic solvents that are soluble or miscible in water.

Suitable aqueous solvents include water, ethanol, propylene glycol, polyethylene glycols (e. g., PEG400, PEG300), etc. and mixtures thereof. A preferred solvent is water.

The formulations may also include one or more buffers, stabilizing agents, surfactants (preferably a micelle- forming surfactant), wetting agents, lubricating agents,

emulsifiers, suspending agents, preservatives, sweeteners, perfuming agents, flavoring agents and other known additives to provide an elegant presentation of the drug.

The term"stabilizing agent"refers to a pharmaceutically acceptable excipient that enhances the chemical and physical stability of the active ingredient in the formulation. Suitable stabilizing agents include polyols (e. g., polyethylene and propylene glycols and carbohydrates such as sucrose, trehalose, fructose, lactose and mannitol), amino acids and surfactants such as polysorbates and bile salts. In solution, most preferred stabilizing agents are the bile salts, polyethylene glycols and propylene glycol.

The formulation may also optionally contain a buffer.

The buffer is generally present at a concentration in the range from about 0. 03% to about 5% (wgt./vol.), more preferably at a concentration in the range from about 0. 1% to about 1%. The term"buffer"refers to a pharmaceutically acceptable excipient that maintains the pH of the solution within a particular range specific to the buffering system.

A suitable pH range is from pH 3. 0 to 7. 0. The preferred range is from 4. 0 to 5. 5, more preferably 4. 0 to 5. 0.

Suitable buffers include acetates, citrates, phosphates, tartrates, lactates, succinates, amino acids and the like.

Preferred buffers for the solution formulation include acetate, citrate, tartrates, phosphate salts and combinations thereof.

The formulations may be prepared using conventional dissolution and mixing procedures. For example, the bulk drug substance (e. g., echinocandin) is dissolved in a suitable solvent in the presence of one or more of the excipients described above. The active ingredient is

typically formulated into pharmaceutical dosage forms to provide an easily controllable dosage of the drug and to give the patient an elegant and easily handleable product.

As used herein, the term"unit dose"or"unit dosage" refers to physically discrete units that contain a predetermined quantity of active ingredient calculated to produce a desired therapeutic effect. The dosage to be administered may vary depending upon the physical characteristics of the patient, the severity of the patient's symptoms, and the means used to administer the drug. The specific dose for a given patient is usually set by the judgment of the attending physician.

A pharmaceutical composition may be administered using a variety of methods. When a unit dose is administered, it is typically provided in the form of an aerosol, powder, topical composition (ointment or spray) or other known form which allows placement of the active ingredient in contact with the fungus residing in the mucus. An aerosol may be inhaled or sprayed in liquid or dry form. The particular treatment method used will depend upon the inflammation being addressed. For example, in treating a mammal having asthma, at least a portion of the airways (e. g., nasal- paranasal airways and lung airways) of the mammal is treated with a medicament containing the echinocandin in an amount, at a frequency, and for a duration effective to reduce or eliminate asthma symptoms.

The mucoadministration of an agent to the nasal- paranasal anatomies can be any type of administration that places the agent in contact with nasal-paranasal mucus.

Direct mucoadministration to the nasal-paranasal anatomies can include, nasal irrigations, nasal sprays, nasal inhalations, and nasal packs with, for example, saturated

gauze provided the administered agent contacts nasal- paranasal mucus prior to crossing epithelium. In addition, injections into the nasal-paranasal cavities using, for example, a needle or catheter tube is considered a direct mucoadministration provided the administered agent contacts nasal-paranasal mucus after leaving the needle or catheter tube and prior to crossing epithelium. Any device can be used to directly mucoadminister an agent to the nasal- paranasal anatomy including, a syringe, bulb, inhaler, canister, spray can, nebulizer, and mask.

Similarly, mucoadministration of an agent to the lung airways can be any type of administration that places the agent in contact with mucosa of the lung (including the bronchi and bronchial tubes). Direct mucoadministration to the lung airways can include, inhalations, nasal sprays, and nasal irrigations provided the administered agent contacts lung airway mucus prior to crossing epithelium. In addition, injections into lung airways using, for example, a needle or catheter tube is considered a direct mucoadministration provided the administered agent contacts lung airway mucus after leaving the needle or catheter tube and prior to crossing epithelium. Any device can be used to directly mucoadminister an agent to the lung airway including, a syringe, bulb, inhaler, nebulizer, aerosol canister, spray can, and mask.

Mucoadministration of an agent to the middle ear can be any type of administration that places the agent in contact with middle ear mucus. The direct mucoadministration to the middle ear can include ear drops and ear flushes provided the administered agent contacts middle ear mucus prior to crossing epithelium. For example, if the tympanic membrane is damaged or otherwise punctured, then an ear flush would

be considered a direct mucoadministration provided the administered agent contacts middle ear mucus. In addition, injections into the middle ear using, for example, a needle or myringotomy tube is considered a direct mucoadministration provided the administered agent contacts middle ear mucus after leaving the needle or tube and prior to crossing epithelium. Any device can be used to directly mucoadminister an agent to the middle ear including, a syringe and bulb.

Mucoadministration of an agent to the intestines can be any type of administration that places the agent in contact with intestinal mucus. The direct mucoadministration to the intestines can include oral and enema administrations provided the administered agent contacts intestinal mucus prior to crossing epithelium. In addition, injections into the digestive tract using, for example, a needle or catheter tube is considered a direct mucoadministration provided the administered agent contacts intestinal mucus after leaving the needle or catheter tube and prior to crossing epithelium. Any device can be used to directly mucoadminister an agent to the intestines including a syringe and regulated release capsule. For example the echinocandin compound can be formulated into a regulated release capsule such that the antifungal agent is released after passing, for example, the stomach (e. g., pH regulated release capsules and time regulated release capsules).

Echinocandin compounds have been shown to exhibit antifungal activity such as growth inhibition of various infectious fungi including Candida spp. (i. e., C. Albicans, C. Parapsilosis, C. Krusei, C. Glabrata, C. Tropicalis, or C. Lusitaniaw) ; Torulopus spp. (i. e., T. Glabrata) ; Aspergillus spp. (i. e., A. Fumigatus) ; Histoplasma spp.

(i. e., H. Capsulatum) ; Cryptococcus spp. (i. e., C.

Neoformans) ; Blastomyces spp. (i. e., B. Dermatitidis) ; Fusarium spp. ; Trichophyton spp., Pseudallescheria'boydii, Coccidioides immits, Sporothrix schenckii, etc.

Consequently, the formulations containing echinocandin compounds described herein are useful in treating or preventing non-invasive fungus-induced mucositis by preventing, eradicating or inhibiting the growth of fungus in the mucus. Accordingly, the echinocandin antifungal agent (including the formulations and processes used therein) may be used in the manufacture of a medicament for the therapeutic applications described herein. For example, fungal activity which induces inflammation may be inhibited by contacting the echinocandin antifungal agent with the inflammation-inducing fungus. The term"contacting" includes a union or junction, or apparent touching or mutual tangency of a compound of the invention with a fungus. The term does not imply any further limitations to the process.

The methods are defined to encompass the inhibition of fungal activity by the action of the compounds and their inherent antifungal properties.

The method for treating or preventing non-invasive fungus-induced mucositis comprises administering an effective amount of a pharmaceutical formulation containing an echinocandin compound to a host in need of such treatment. The term"effective amount"refers to an amount of active compound which is capable of inhibiting fungal activity. The dose, frequency and duration will vary depending on such factors as the nature and severity of the inflammation, the age and general health of the host and the tolerance of the host to the antifungal agent. The medicament may be given in a single daily dose or in

multiple doses during the day. The regimen may last from about 2-3 days to several weeks, months, or a year or longer. In addition, chronic administration of the medicament, for example over the lifetime of the host, would be useful for prevention of recolonization of the mucosal surface by fungi, and would thereby prevent recurrence of chronic rhinosinusitis (or other) symptomology. A typical daily dose (administered in single or divided doses) contains a dosage level sufficient to reduce inflammation caused by the presence of the fungal organisms, generally between about 0. 001 mg/kg to 500 mg/kg of body weight of an active compound.

EXAMPLES The following example describes the preparation of an echinocandin compound that may be used in the present invention. Specifically, the following sequence describes the preparation of echinocandin compound 6 (a) having the following structure :

It will be understood by those skilled in the art that the following serves as an illustrative example and that other semi-synthetic echinocandin compounds useful as anti-fungal agents may be synthesized using similar procedures or procedures described in references cited earlier in the specification. Materials used in the following preparations are available from Aldrich Chemicals (Milwaukee, Wisconsin) unless designated otherwise.

Compound Preparations Preparation of 4-Bromo-4'-pentyloxybiphenyl 7 (a) : Anhydrous K2CO3 (416g, 3mol) was added to a mixture of 4-bromo-4'-hydroxybiphenyl (300g, 1. 2mol), 1-iodopentane (234ml, 1. 79mol) and 2-butanone (600ml). The reaction mixture was refluxed for 44h until TLC (85 : 15 hexanes/EtOAc) showed complete consumption of the bromo alcohol. The mixture was cooled to about 30°C, diluted with CH2C12 (600ml) and then filtered. The filtrate was washed twice with H2O and twice with a saturated aqueous NaCl solution, dried over anhydrous Na2SO4, filtered and then dried at reduced pressure to provide a solid. This solid was isolated by filtration, washed repeatedly with a total of 2L of ice-cold heptane to remove all traces of iodopentane and then dried overnight under high vacuum. Yield : 340g (88%) of a white powder.

Alternative Preparation of 4-bromo-4'-pentyloxybiphenyl l (a) : 4-Bromo-4'-hydroxybiphenyl (12. 5g, 50. 2mmol) was added to a solution of NaOH (2. 28g, 97% pure, 55. 2mmol) in deionized H2O (150ml), followed by the addition of

1-iodopentane (11. 9g, 60. 2mmol) and tetrabutylammonium bromide (0. 82g, 2. 51mmol). The mixture was stirred at 90°C for 3. 75h until the solids went into solution. Then, as the reaction proceeded, the desired product began to precipitate. The mixture was slowly cooled and then filtered to provide a solid which was washed with deionized water until the pH of the filtrate was neutral and then dried for 16h in a vacuum oven at 30°C.

Yield : 15. 41g (96%) of 5a. Rf 0. 5 (97 : 3 hexanes/EtOAc).

H NMR : 8 0. 93 (t, 3H, J=6. 9Hz) ; 1. 41 (m, 4H) ; 1. 79 (m, 2H) ; 3. 97 (t, 2H, J= 6. 6Hz) ; 6. 98 (m, 2H) ; 7. 23 (m, 6H).

3C MMR : 8 14. 03 ; 22. 43 ; 28. 22 ; 28. 98 ; 68. 12 ; 114. 91 ; 120. 71 ; 127. 93 ; 128. 27 ; 131. 77 ; 132. 24 ; 139. 82 ; 159. 03.

MS (FAB+) : m/z 320. IR (CHC13) : 2960, 2936, 2874, 1608, 1518, 1485, 1475 crd-3-. Analysis for Cl7HlgBrO : Calcd : C, 63. 96 ; H. 6. 00 ; Br, 25. 0 ; Found : C, 64. 10 ; H. 5. 97 ; Br, 25. 28.

Preparation of 4-Boronic acid-4'-pentyloxybiphenyl 2 (aJ : To a cold (-20°C) mixture of Compound l (a) (lOOg, 0. 31mol) in t-butylmethylether (MTBE) (1L), was slowly added n-butyl lithium (150ml of a 2. 5M hexanes solution, 0. 37mol) dropwise under N2, while maintaining the internal temperature between-19° and-18°C. The resultant mixture was stirred for 3. 5h between-17° and-16°C which resulted in light yellow-green solution. This solution was cooled to -78°C and diluted with 100ml of anhydrous THF which resulted in a white precipitate. Then, a cold (-78°C) solution of triisopropylborate (145ml, 0. 62mol) in MTBE (200ml), under nitrogen was added dropwise over 1. 5h while maintaining the reaction temperature between-78° and-74°C. The resultant reaction mixture was stirred for 1. 5h at-78°C, then allowed

to warm to-50°C over Ih at which time the cooling bath was removed and the mixture was stirred overnight (16-21h) which resulted in a white precipitate. The mixture was shaken vigorously with 2M HC1 (1000ml) for 5 minutes and then the resulting layers were separated and the organic layer was dried at reduced pressure to provide a residue. This residue was diluted with MTBE (100ml), followed by heptane (800ml) to provide a white powder which isolated by suction filtration and washed 3 times with heptane (300ml).

Yield : 88g (98%). Rf 0. 45 (95 : 5 CH2Cl2/MeOH). 1H NMR : 8 0. 92 (m, 3H) ; 1. 41 (m, 4H) ; 1. 80 (m, 2H) ; 4. 00 (m, 2H) ; 6. 99 (m, 2H) ; 7. 45-7. 63 (m, 3H) ; 7. 67 (m, 2H) ; 8. 24 (d, 1H, J=8. 3Hz). 13C NMR : 14. 01 ; 22. 26 ; 28. 03 ; 28. 77 ; 39. 61 ; 39. 89 ; 40. 17 ; 40. 45 ; 67. 82 ; 114. 77 ; 125. 32 ; 127. 83 ; 132. 93 ; 134. 84 ; 141. 88 ; 158. 71. MS (FD+) : m/z 284. IR (CHC13) : 2959, 2952, 2874, 1606, 1526, 1500 ci-1.

Preparation of Compound 3 f a) : A solution of toluene (174ml) and propanol (20ml) was degassed 3 times by applying vacuum to the solution for 20- 30 seconds followed by purging with N2. A 2M solution of Na2C03 was also degassed. The toluene/propanol solution (97ml) was added to a mixture of methyl 4-iodobenzoate (14. 12g, 53. 9mmol) and Compound 2 (a) (15. 0g, 52. 8mmol), followed by a degassed 2M aqueous Na2C03 solution (29ml, 58. Ommol). The resultant mixture was degassed 2 times for 20-30 seconds each under a positive pressure of N2, followed by the addition of palladium (II) acetate (0. 24g, l. lmmol) and triphenylphosphine (0. 84g, 3. 2mmol) and then degassed 2

more times. The reaction mixture was then refluxed under N3 for 5h resulting in a light-yellow mixture. This mixture was cooled to 23°C resulting in the formation of a precipitate which was collected by filtration, washed successively with toluene (123ml), 2 : 1 MTBE/EtOAc (143ml), deionized water (123ml) and 2 : 1 MTBE/EtOAc (42ml) and then dried for 16h in a vacuum oven at 35°C. Yield : 18. 7g (94%).

Rf 0. 48 (benzene). H NMR : 8 0. 93 (t, 3H, J=6. 80Hz) ; 1. 42 (m, 4H) ; 1. 81 (m, 2H) ; 3. 95 (s, 3H) ; 4. 00 (t, 2H, J= 6. 48 Hz) ; 6. 97 (d, 2H, J=8. 52Hz) ; 7. 55 (d, 2H, J= 8. 52Hz) ; 7. 66 (m, 6H), 8. 10 (d, 2H, J=8. 20Hz). MS (FD+) : m/z 374.

IR (KBr) : 2938, 1723 cm-Analysis for C25H2603 : Calcd : C, 80. 18 ; H. 7. 00 ; Found : C, 79. 91 ; H. 6. 94.

Preparation of Compound 4 (a) : A mixture of Compound 3 (a) (80g, 0. 21mol), 5M KOH (160ml) and cetyltrimethylammonium bromide (4. 8g, 0. 013mol) in xylene (800ml) was refluxed for 3h and then cooled to 10°C and filtered to provide a white solid. This solid was washed 3 times with H20 (500ml each) to remove the catalyst and most of the base. The resultant material was treated with DME (500 ml). The pH of the solution was adjusted to pH by the addition of 6M HC1 (100ml). The resultant mixture was refluxed for 30 minutes while periodically checking the pH to assure that it remained acidic, then cooled and filtered. The resulting solid was washed successively with MTBE (400ml) and water (4x400ml) until the washings were neutral to litmus. Yield : 76 g (98% yield).

1H NMR 8 0. 89 (t, 3H, J= 6. 82Hz), 1. 38 (m, 4H), 1. 73 (m,

2H), 3. 96 (t, 2H, J= 6. 3Hz), 6. 95 (d, 2H, J=8. 56Hz), 7. 57 (d, 2H, J=8. 54Hz), 7. 64-7. 74 (m, 6H), 8. 00 (d, 2H, J=8.2lHz), 8. 09 (s, 1H). MS (FD+) m/z 360. IR (KBr) : 2958, 2937, 2872, 1688 cni-1. Analysis for C24H2403 : Calcd : C, 79. 97 ; H. 6. 71 ; Found : C, 80. 50 ; H. 6. 77.

Preparation of HOBT ester of Compound 4 (a) : A. Formation of HOBT mesylate To a cold (0°C) mixture of hydroxybenzotriazole hydrate (200g, 1. 48mol) in anhydrous CH2C12 (1. 5L), was slowly added anhydrous Et3N (268ml, 1. 92mol) while maintaining a temperature of 0-10°C, followed by the addition of methanesulfonyl chloride (126ml, 1. 63mol) while maintaining a temperature of 0-5°C. The resultant mixture was stirred for 3h at 0°C and washed successively with cold water (2 x 1. 2L) and brine (1. 2L). The combined organic extracts were concentrated at reduced pressure to provide a solid. This solid was recrystallized from CH2Cl2 (100ml) and heptane (1L). The crystals were collected by suction filtration and washed repeatedly with a total of 1. L of heptane and then dried overnight under high vacuum (0. 5 mm Hg). Yield : 245g (78%) Rf 0. 55 (1 : 1 hexanes/CHzCl2). 1H NMR : 8 3. 58 (s, 3H), 7. 46 (t, 1H, J= 7. 60Hz), 7. 60 (d, 1H, J= 8. 28 Hz), 7. 65 (d, 1H, J= 8. 56Hz), 7. 68 (d, lH, J= 8. 20 Hz), 8. 05 (d, 1H, J=8. 41Hz).

B. Formation of HOBT ester A mixture of Compound 4 (a) (50g, 0. 14mol) and the material described above in part A (36g, 0. 17mol) in DMF (650ml) was treated dropwise with Et3N (25ml, 0. 18mol), under N2. The resultant mixture was stirred for 4h at room temperature until all the acid was consumed, as determined by TLC (95 : 5 CH2Cl2/MeOH). When all the acid was consumed,

an aliquot of the reaction mixture (-3 pipes drops) gave a clear homogeneous solution when diluted with 3ml of 1 : 1 CH2C12/THF. The reaction mixture was then diluted with toluene (500ml), washed with water (500ml). The organic layer (containing solid product) was diluted with water (500ml) and filtered using MTBE for transferring. The solid was rinsed with MTBE (2 x 400ml) and dried under vacuum to provide green-white flakes of material. NOTE : This material could be dissolved in THF and filtered to remove any remaining metal contamination. Yield : 61g (92%).

Rf 0. 68 (1 : 1 CH2Cl2/hexanes). 1H NMR : 8 0. 93 (t, 3H, J=7. OHz), 1. 42 (m, 4H), 1. 81 (m, 2H), 4. 00 (t, 2H, J=6. 53Hz), 6. 99 (d, 2H, J=8. 6Hz), 7. 42-7. 59 (m, 5H), 7. 71 (dd, 4H, J=13. 91Hz, 8. 40Hz), 7. 86 (d, 2H, J=8. 30Hz), 8. 11 (d, 1H, J= 8. 31Hz), 8. 35 (d, 2H, J=8. 33Hz). 13C NMR : 8 14. 03, 22. 44, 28. 18, 28. 94, 40. 10, 40. 37, 68. 11, 108. 45, 110. 11, 114. 95, 118. 71, 120. 48, 123. 04, 124. 94, 124. 99, 127. 00, 127. 23, 127. 51, 127. 73, 128. 06, 128. 82, 128. 86, 131. 35, 132. 30, 137. 15, 141. 43, 143. 54, 147. 85, 159. 15, 162. 73. MS (FD+) : m/z 477. IR (CHC13) : 2960, 2936, 2874, 1783, 1606 cm 1. Analysis for C30H27N303 : Calcd : C, 75. 45 ; H, 5. 70 ; N, 8. 80 ; Found : C, 75. 69 ; H, 5. 58 ; N, 8. 92.

Preparation of Anti-fungal Compound 6 (a) : Deionized water was used throughout the procedure. A mixture of Compound 5 (a) (llg, 23mmol) and the nucleus of Compound 6 (a) (where R is hydrogen-92% pure by HPLC, 19. 25 g, 22. 2mmol) in anhydrous DMF (275ml) was stirred, under N2 for 4h (until HPLC showed complete consumption of the cyclic peptide starting material). The mixture was filtered through a bed of celite and the filtrate was concentrated under reduced pressure at 35°C to provide a paste that could

be stirred. This paste was poured into MTBE (500ml) which resulted in the precipitation of a fine powder which was collected by vacuum filtration and dried to provide 27g of crude material. This material was crushed to a powder with a mortar and pestle, slurried for 5 minutes in toluene (200ml), suction filtered (slow filtered), rinsed with MTBE (100ml) and then dried in vacuo to provide a yellow solid.

Yield : 23 g (95% pure by HPLC, retention time = 7. 79 min).

Alternatively, the conversion may be carried out using an excess of the cyclic nucleus (1. 1 equiv.). When the reaction is substantially complete, as indicated by HPLC, the crude material (lOg of a powder) is added portion-wise to a vigorously stirred mixture of 9 : 1 acetone/water (60ml).

Celite (2. 5 g, pre-washed with a 9 : 1 acetone/water mixture) is added to the resultant suspension. After stirring for 2 minutes, the mixture is filtered through a bed of celite (prewashed with 9 : 1 acetone/water) and the cake is rinsed twice with 9 : 1 acetone/water (10ml). The filtrate is poured into a beaker of deionized water (200ml) while gently swirling the mixture which resulted in the formation of a precipitate. This precipitate is collected by suction filtration, rinsed with H20 (4 x 25ml), and then dried in vacuo at room temperature. Yield : 6. 81g (97% pure by HPLC).

The product was further purified using preparatory HPLC chromatography. Rf 0. 29 (80 : 20 CHC13/MeOH). MS (FAB+) : m/z for C58H74N707, Calcd : 1140. 5141 ; Found : 1140. 5103.

IR (KBr) : 3365, 2934, 1632, 1518 cm-.

Tables I & II below summarize the test results for Compound 6 (a) against a broad spectrum of fungal strains using the NCCLS Standard Reference Method M27-T (Table I and the agar dilution test (Table II).

Table I 5. patin Compound 6 (a) Strain ts MIC (ug/ml) Amphotericin B coloniz (n=number of MIC (µg/ml) ed with isolates) species Alternaria 44. 3 #0. 125-0. 625 0. 39 (n=l) (n=4) Aspergillus 29. 5 A. flavus < 0. 005-10. 0 0. 39-4. 0 (n=5) A. fumigatus (n=7) 0. 39-2. 0 (n=7) A. versicolor < 0. 00125-10. 0 1. 0 (n=2) (n=8) 0. 005 (n=2) Candida 21. 4 C. albicans < 0. 005-0. 16 #0. 0313-1. 0 C. (n=99) (n=99) parapsilosis 1. 25-5. 0 (n=ll) 0. 25-1. 0 (n=ll) Cladosporium 39. 0 0. 312 (n=l) 0. 195 (n=l) Penicillium 43. 3 < 0. 02 (n=l) 0. 098 (n=l) Fusarium 16. 2 8 to > 64 (n=21) 0. 78 (n=l)

Table II Test Organism MIC Range (Rg/ml) (No. of Strains) Compound 6 (a) Amphotericin B C. albicans (107) 0. 002-0. 625 0. 312 to >2 C. guilleimondii (11) 0. 002-10 2. 5 to >20 C. krusei (14) <0. 009-0. 625 5. 0-10 C. laurentii (2) <0. 001 0. 625 C. lusitanea (5) <0. 009 5-10 C. parapsilosis (17) 0. 078-0. 625 10 to >20 C. tropicalis (21) 0. 001-0. 156 1. 25 to >20 C. pseudotropicalis (2) 0. 001-0. 08 2. 5-20 C. stellatoidea (3) 0. 005-0. 312 2. 5-20 Torulopsis glabrata (19) 0. 001-2. 5* 2. 5-20 *All isolates but 1 were <0. 2 Rg/ml In most of the fungal strains, the echinocandin compound provided better antifungal activity than the comparative Amphotericin B compound. Unlike the azole antifungal agents, it is believed that the echinocandins have a lower potential for the development of resistant strains. In addition, the echinocandins generally have less side effects and a superior toxicity profile than the comparative Amphotericin B. For example, Compound 6 (a) has an acute toxicity in a murine model of greater than 100 mg/kg when administered by the IV route ; whereas, Amphotericin B has an acute toxicity, as measured in a murine model, of 4 mg/kg (LDso).