AU2004268895B2 - Caspase inhibitors containing isoxazoline ring - Google Patents

Description

Description CASPASE INHIBITORS CONTAINING ISOXAZOLINE RING

[i] TECHNICAL FIELD

[2]

[3] The present invention relates to an isoxazcfine derivative as an inhibitor against various caspases including caspase-l[interleukin-lβ converting enzyme, ICE] and caspase-3[apopain/CPP-32], a process for preparing the same, and a therapeutic composition for preventing inflammation and apoptosis comprising the same.

[4] BACKGROUND ART

[5]

[6] Caspase is a new kind of cysteine protease in the form of α β discovered during the last 10 years. About 14 kinds thereof have been known until now. Caspase- 1 (ICE), one of them, is a kind of cytokines and participates in converting the inactive proin- terleukin-lβ to the active interleukin-lβ. Interleukin-1 consists of interleukin-lα and interleukin-lβ, both of which are synthesized in monocytes in the form of a precursor having 3 lkDa. Only prointerleukin-lβ is activated by ICE. The positions hydrdyzed by caspase- 1 are Asp -Gly^" and Asp -Ala . The hydrolysis of the latter position gives interleukin-lβ. Interleukin-lβ has been reported to act as an important mediator in causing inflammation (1,3). Caspase-1 has been discovered for the first time in 1989, and in two independent study groups, the three dimensional structure thereof was determined by X-ray crysta ographic method.

[7]

[8] Caspase-3(CPP-32) is broady studied for its rde or mechanism for action, and its three dimensional structure was determined in 1996(2). Caspase-3(apopain) activated from procaspase-3 hydrdyzes (P4)Asp-X-X-Asp(Pl) motif, and the known substrates include pdy(ADP-ribose) pdymerase, Ul 70,000 Mr smal nuclear ribonucleoprotein and catalytic subunit of 460,000 Mr DNA-dependent protein kinase, etc. The X-ray structure of caspase-7 has been reported to be very similar to that of caspase-3(4).

[9]

[10] Caspase-8 and 9 are present in the upstream of caspase-3,6,7, and these caspases are known to participate in the apoptosis cascade. The X-ray structure of caspase-8 was determined in 1999(5), and particularly the inhibitors thereof may be advantageously used for treating the diseases related to apoptosis.

[11]

[12] Caspase inhibitors mean those compounds that inhibit the activity of caspase, and so contrd such symptoms as inflammation, apoptosis, etc. caused by the caspase activity. Diseases or symptoms that may be treated or attenuated by administering the inhibitors include the fdtawing: reumatoid arthritis, inflammatory bowel disease, graft vs. host disease, sepsis, osteoarthritis, osteoporosis, acute and chronic myebgenous leukemia, meningitis, salpingitis, septic shock, chdangitis, colitis, encephalitis, endocarditis, gtomembnephritis, hepatitis, myocarditis, pancreatitis, type I diabetes meltus, multiple sclerosis, Alzheimer's disease, Parkinson's disease, hepato- cirrhosis(6).

[13]

[14] Among the caspase inhibitors known until now, the most noted irreversible inhibitors are the following:

[15]

IDN-1965 MX-1013

[16]

[17] Both the above inhibitors exhibit their activity based on the common mechanism that they irreversibly inactivate the enzyme to suppress the eel apoptosis (irreversible, broad-spectrum inhibitor). It has been reported that irreversible inhibitor has much more effective inhibitory activity when comparing the irreversible and reversible inhibitors (7). Both IDN-1965 of IDUN Co. and MX-1013 of Maxim Co. are reported to show activity in eel apoptosis model for hepatic injury(8, 9). These compounds are now in the stage of precϋnical test. The irreversible inhibitor IDN-6556, the structure of which has been recently reported, is now in the stage of phase II clinical test as a therapeutic agent for hepatic injury(10, 11).

[18] EDN-6556 [19]

[20] References:

[21] (1) Inflammation: Basic Principles and Clinical Correlates, 2nd ed., ed by Gain, Gddstein and Snyderman. Raven Press Ltd., New York . 1992, pp211-232; Blood, 1996, 87(6), 2095-2147. [22] (2) Wilson, K. P. et al, Nature, 1994,370. 270; Walker, N. P. C. et al. Cell, 1994, 78, 343; Nature Structural Biology, 1996, 3(7), 619. [23] (3) Thornberry, N. A. et al, Nature, 1992,356. 768; Nature Biotechnology, 1996, 14 , 297; Protein Science, 1995, 4, 3; Nature, 1995, 376(July 6) , 37; Protein Science, 1995, ^, 2149. [24] (4) Wei, Y. et al, Chemistry and Biology, 2000, 7, 423.

[25] (5) Blanchard H. et al, Structure, 1999, 7, 1 125; Blanchard H. et al, J. ofMol. Biol., 2000, 302, 9. [26] (6) References for caspase related diseases

[27] Dementia: Arch Neurd 2003 Mar;60(3):369-76, Caspase gene expression in the brain as a function of the clnical progression of Alzheimer disease. Pompl PN, Yemul S, Xang Z, Ho L, Haroutunian V, Purohit D, Mohs R, Pasinetti GM. [28] [29] Cerebral stroke: Proc Natl Acad Sci U S A 2002 Nov 12;99(23): 15188-93, Caspase activation and neuroprotection in caspase-3- deficient mice after in vivo cerebral ischemia and in vitro oxygen glucose deprivation. Le DA, Wu Y, Huang Z, Matsushita K, Plesnila N, Augustinack JC, Hyman BT, Yuan J, Kuida K, Flavel RA, Moskowitz MA. [30] [31 ] Brain impairment due to AIDS : J Neurosci 2002 May 15 ;22( 10) :4015-24, Caspase cascades in human immunodeficiency virus-associated neurodegeneration. Garden GA, Budd SL, Tsai E, Hanson L, Kaul M, D'Emilia DM, Friedander RM, Yuan J, Masϋah E, Lipton SA. [33] Dabetes: Dabetes 2002 Jun;51 (6): 1938-48, Hyperglycemia-induced apoptosis in mouse myocardium: mitochondria! cytochrome C-mediated caspase-3 activation pathway. Cai L, Li W, Wang G, Guo L, Jiang Y, Kang YJ.

[34]

[35] Gastric ulcer: J Physid Pharmacd 1998 Dec;49(4):489-500, Rde of basic fibroblast growth factor in the suppression of apoptotic caspase-3 during chronic gastric ulcer healing. Stomiany BL, Piotrowski J, Sfomiany A.

[36]

[37] Cerebral injure by hepatitis: J Viral Hepat 2003 Mar; 10(2): 81-6, Cerebral dysfunction in chronic hepatitis C infection. Forton DM, Taybr-Robinson SD , Thomas HC.

[38]

[39] Fulminant hepatic failure: Gastroenterdogy 2000 Aug;l 19(2):446-60, Tumor necrosis factor alpha in the pathogenesis of human and murine fulminant hepatic failure. Streetz K, Leifeld L, Grundmann D, Ramakers J, Eckert K, Spengler U, Brenner D, Manns M, Trautwein C.

[40]

[41] Sepsis: Nat Immund 2000 Dec;l(6):496-501, Caspase inhibitors improve survival in sepsis: a critical rde of the lymphocyte. Hotchkiss RS, Chang KC, Swanson PE, Tinsley KW, Hui JJ, Klender P, Xanthoudakis S, Roy S, Black C, Grimm E, Aspiotis R, Han Y, Nchdson DW, Karl IE.

[42]

[43] Organ transplantation rejection: Xenotransplantation 2001 May;8(2): 115-24, In vitro prevention of eel-mediated xeno-graft rejection via the Fas/FasL-pathway in CrmA-transducted porcine kidney eels. Fujino M, Li XK, Suda T, Hashimoto M, Okabe K, Yaginuma H, Mikoshiba K, Guo L, Okuyama T, Enosawa S, Amemiya H, Amano T, Suzuki S.

[44]

[45] Rheumatic arthritis: Prog Med Chem 2002;39:1-72, Caspase inhibitors as anti- inflammatory and antiapoptotic agents. Graczyk PP.

[46]

[47] Ischemic cardiac diseases: Am J Physid Heart Circ Physid 2002 Sep;283(3):H990-5, Hypoxia-induced cleavage of caspase-3 and DFF45/ICAD in human failed cardiomyocytes. Todor A, Sharov VG, Tanhehco EJ, Silverman N, Bernabei A, Sabbah HN. [48]

[49] Anti-inflammation: J Immund 2003 Mar 15;170(6):3386-91, A broad-spectrum caspase inhibitor attenuates alergic airway inflammation in murine asthma model. Iwata A, Nshio K, Winn RK, Chi EY, Henderson WR Jr, Harlan JM.

[50]

[51 ] Cirrhosis : i) J Pharmacd Exp Ther. 2004 Mar;3C8 (3) : 1191 -6, The caspase inhibitor Idn-6556 attenuates hepatic injury and fibrosis in the bile duct Kgated mouse. Canbay A., Fledstein A., Baskin-Bey E., Bronk FS. Gores GJ.; ii) Hepatofogy. 2004 Feb;39(2):273-8, Apoptosis: the nexus of liver injury and fibrosis. Canbay A, Friedman S, Gores GJ.; iii) Hepatobgy. 2003 Nov;38(5): 1188-98, Kupffer eel engulfment of apoptotic bodies stimulates death Hgand and cytokine expression. Canbay A, Feldstein AE, Higuchi H, Wemeburg N, Grambihler A, Bronk SF, Gores GJ.

[52]

[53] (7) Wu J. et al, Methods: A Companion to Methods in Enzymology, 1999, 17, 320.

[54] (8) Hoglen N. C. et al, J. of Pharmacoloy and Experimental Therapeutics , 2001, 297, 811.

[55] (9) Jaeschke H. et al, Toxicology and Applied Pharmacology , 2000, 169, 77.

[56] (10) Hoglen N.C. et al, J. Pharmacol Exp. Ther., 2004, 309(2):634. Characterization of IDN-6556 (3-[2-(2-tert-butyl-phenylaminooxalyl)-amino] - propionylamino]-4-oxo-5-(2,3,5,6-tetraflιoro-phenoxy)-pentanoic acid): a Hver- targeted caspase inhibitor;

[57] (11) Canbay A et al, J. Pharmacol. Exp. Ther., 2004, 306(3), 1191. The caspase inhibitor IDN-6556 attenuates hepatic injury and fibrosis in the bile duct Hgated mouse.

[58] DISCLOSURE OF THE INVENTION

[59]

[60] The present inventors newly designed and synthesized some compounds which can be used as an effective inhibitor against caspases and have a distinctive structure and high selectivity for similar enzymes, and determined their binding ability and inhibitory activity for caspases. As a resdt, the inventors have discovered that a compound of the following formula (1) does meet such requirements, and completed the present invention.

[61]

[62] (1)

[63] in which

[64] A, B, R, R , R and X are defined as described below.

[65]

[66] Therefore, the present invention provides the novel isoxazoϋne derivative of formula (1), salt, or stereoisomer thereof having effective inhibitory activity against caspases.

[67]

[68] It is another object of the present invention to provide a process for preparing the compound of formula (1), salt, or stereoisomer thereof.

[69]

[70] It is also another object of the present invention to provide a composition, a use, or a method for inhibiting caspases, specificaly a therapeutic composition, a use, or a method for preventing inflammation and apoptosis, comprising the compound of formula (1), salt, or stereoisomer thereof as an active ingredient together with the phar- maceuticaly acceptable carrier.

[71] BRIEF DESCRIPTION OF THE DRAWINGS

[72]

[73] Figure 1 shows the inhibitory activity of Compound (Iii) against the hepatic fibrosis due to the bile stagnation: "a)" in Figure 1 represents the case of Sham operati on,"b)" represents the case of BDL operation where only the vehicle was administered after the ligation of biliary duct, "c)" represents the case where Compound (Iii) was oraly administered in a dosage of 3 mg / kg twice a day for 1 week after 1 week from the ligation of blary duct, and "d)" represents the case where Compound (Iii) was oraly administered in a dosage of 10 mg / kg twice a day for 1 week after 1 week from the igation of biliary duct.

[74]

[75] Figure 2 shows the inhibitory activity of Compound (Iii) against the hepatic eel apoptosis due to the bile stagnation: "a)" in Figure 2 represents the case of Sham operation, "b)" represents the case of BDL operation where only the vehicle was administered after the ligation of bffiary duct, "c)" represents the case where Compound (Iii) was oraly administered in a dosage of 3 mg / kg twice a day for 1 week after 1 week from the ligation of biliary duct, "d)" represents the case where Compound (Iii) was oraly administered in a dosage of 10 rag / kg twice a day for 1 week after 1 week from the ligation of biliary duct, and "e)" is a graph showing the number of hepatic eels subjected to apoptosis in each treatment group.

[76] BEST MODE FOR CARRYING OUT THE INVENTION

[77]

[78] In advance of illustrating the present invention in detail, the fdtawing important terms are defined first:

[79] a) Simple Alkyl Chain (SAC, below) means a hydrocarbon having 1 to 8 carbon atoms in either linear or branched isomeric form.

[80]

[81] b) Simple Cyclo Alkyl Chain (SCAC, below) means a cyclic radical having 3 to 10 carbon atoms.

[82]

[83] c) Aryl group (Ar, below) includes both the aromatic and heteroaromatic groups. The aromatic group means a 5 to 15-membered single or fused unsaturated cycle. One or more hydrogens may be replaced with a group(s) selected from the fdtawing: acyl, amino, carboalkoxy, carboxy, carboxyamino, cyano, hato, hydroxy, nitro, thid, alkyl, cyctoalkyl, alkoxy, arytoxy, sulfoxy, and guanido group. The heteroaromatic group means the aromatic group containing 1 to 5 hetero atoms selected from a group consisting of oxygen, sdfur, and nitrogen. Likewise, one or more hydrogens may be replaced with a group(s) selected from the following: acyl, amino, carboalkoxy, carboxy, carboxyamino, cyano, hato, hydroxy, nitro, thid, alkyl, cyctoalkyl, alkoxy, aryl, arytoxy, sulfoxy, and guanido group. Or, for example, in the case of pyridyl, an alkyl group can be added to the nitrogen atom to convert the pyridyl group to a pyridinium group having (+)-charge on the nitrogen atom.

[84]

[85] The aryl group includes phenyl, biphenyl, 1-naphthyl, 2-naphthyl, pyridinyl, N- alkyl-pyridinium, pyrimidinyl, quindinyl, benzothienyl, inddyl, pyrazinyl, isoinddyl, isoquindyl, qunazdinyl, quinoxalinyl, phthalazinyl, imidazolinyl, isoxazdyl, pyrazdyl, oxazdyl, thiazdyl, indcfizinyl, indazdyl, benzothiazdyl, benzimidazdyl, benzofuranyl, thienyl, pyrrdyl, oxadiazdyl, thiadiazdyl, triazdyl, tetrazdyl, oxa- zotopyridinyl, imidazopyridinyl, isothiazdyl, cinndinyl, carbazdyl, isochromanyl, chromanyl, tetrahydroisoquindmyl, isoindcfinyl, isobenzotetrahydrofuranyl, isoben- zotetrahydro-thienyl, isobenzothienyl, benzoxazdyl, pyridopyridinyl, benzotetrahy- drofuranyl, benzotetrahydrothienyl, purinyl, benzodioxdyl, triazinyl, phenoxazinyl, phenothiazinyl, pteridinyl, benzothiazdyl, imidazopyridinyl, imidazothiazdyl, dihy- drobenzisoxazinyl, benzisoxazinyl, benzoxazinyl, dihydrobenzisothiopyranyl, ben- zopyranyl, benzothiopyranyl, coumarinyl, isocoumarinyl, chromonyl, chromanonyl, pyridinyl-N-oxide, tetrahydroquindinyl-N-oxide, dihydroquindinyl, dihydro- quindinonyl, dihydroisoquinolinonyl, dihydrocoumarinyl, dihydroisocoumarinyl, isoindoϋnonyl, benzodioxanyl), benzoxazctinonyl, N-alkyl-pyridium, pyrrdyl- N-oxide, pyrimidinyl-N-oxide, pyrazinyl-N-oxide, quindinyl-N-oxide, inddyl- N-oxide, indoϋnyl-N-oxide, isoquindyl-N-oxide, qunazdinyl-N-oxide, quinoxaϊnyl- N-oxide, phthalazinyHM-oxide, imidazolinyl-N-oxide, isoxazdyl-N-oxide, oxazdyl- N-oxide, thiazdyl-N-oxide, indolizinyl-N-oxide, indazdyl-N-oxide, benzothiazdyl- N-oxide, benzimidazdyl-N-oxide, pyrrdyl-N-oxide, oxadiazdyl-N-oxide, thiadiazdyl-N-oxide, triazdyl-N-oxide, tetrazdyl-N-oxide, etc.

[86]

[87] d) Simple Alkyl Chain substituted by Aryl (SAC-Ar, below) means a straight-chain or branched alkyl which has 1 to 8 carbon atoms and is substituted by the above mentioned aryl group.

[88]

[89] e) Natural amino acid includes the following: Glycine, Alanine, Vaϋne, Leucine, Isdeucine, Serine, Threonine, Cysteine, Methionine, Proϋne, Aspartic acid, Asparagine, Gkitamic acid, Glutamine, Lysine, Arginine, Histidine, Phenylalanine, Tyrosine, and Tryptophan

[90]

[91] f) The protecting group of simple ester is a hydrocarbon having 1 to 8 carbon atoms in either linear or branched isomeric form.

[92]

[93] Further, the present specification includes the following abbreviations:

[94] N-chtorosuccinimide: rCS

[95] N-methylmorpholine: NMM

[96] 0-(7-azabenzotriazd- 1 -yl)-N,N,N',N'-tetramethyluroniumhexafluorophosphate : HATU

[97] N,N-dimethyl formamide: DMF

[98] l-(3-dimethylaminopropyl)-3-ethylcarbodiimide: EEC [99] 1-hydroxybenzotriazde hydrate: HOBt

[100] trifluoroacetic acid: TFA

[101] t-butoxycarbonyl: Boc

[102] benzybxycarbonyl: Cbz

[103] methyl: Me

[104] ethyl: Et

[105] equivalent: Eq

[106]

[107] The substituents included in the above formula (1) are specifϊcaly defined as follows.

[103] I) R represents H, simple alkyl chain (-SAQ, simple cyctoalkyl chain (-SCAQ, aryl group (-Ar), or simple alkyl chain substituted by aryl (-SAC-Ar),

[109]

[110] II) R represents -SAC, -SCAC, -Ar, -SAC-Ar, or a side chain residue of al the natural amino acids; and the compound of formula (1) may exist in a specific di- astereomeric form, or mixtures thereof when the carbon to which R is attached becomes a stereocenter due to the R group; or the compound of formula (1) may have a protecting group in an ester form (-00 R wherein R is -SAQ or a sulfonamide 4 4 form (-CONHSO R wherein R is -SAQ, or may exist in the form of pharmaceuticaly acceptable salt, when R is a side chain residue of an amino acid containing carboxyl moiety; or the compound of formula (1) may also exist in the form of pharmaceuticaly acceptable salt when R is a side chain residue of an amino acid containing a base moiety,

[111]

[112] III) R represents -SAC, -SCAC, -Ar, -SAC-Ar, or a side chain residue of the natural amino acids; and the compound of formula (1) may exist in a specific di- astereomeric form, or mixtures thereof when the carbon to which R is attached becomes a stereocenter due to the R group; the compound of formula (1) may have a protecting group in an ester form (-CO R wherein R is -SAQ or a sulfonamide form 6 6 ^ (-C01SHSO R wherein R is -SAQ, or may exist in the form of pharmaceuticaly acceptable salt, when R is a side chain residue of an amino acid containing carboxyl moiety; or the compound of formula (1) may also exist in the form of pharmaceuticaly 2 acceptable salt when R is a side chain residue of an amino acid containing a base 2 7 7 moiety, or R further represents H; -(CH ) OR wherein R is -SAC, -SCAC, -Ar, or - 2 n SAC-Ar, and n = 1 or 2; or -(CH ) OC(=0)R wherein R is -SAC, -SCAC, - Ar, or - 2 n SAC-Ar, and n = 1 or 2,

[113]

[114] IV) A represents -(CH ) - (n = 0-4), -0-(CH ) - (n = 0-4), or -NR⁹-(CH ) - (n = 0- 2 n 2 π 2 n 4) wherein R is -SAC, -SCAC, -Ar, or -SAC-Ar, [115]

[116] V) Brepresents H, -SAC, -SCAC, -Ar, or -SAC-Ar, or

[117] [118] VI) R and R may form a cycle together with the carbon atom to which they are attached, where -R-R¹- is -(CH ) -, -(CH ) -0-(CH ) -, or -(CH ) -NR¹⁰-(CH ) - 2 n 2 n 2 m 2 n 2 m wherein n+m<9 and R is -SAC, -SCAC, -Ar, -SAC-Ar, -C(=0)- SAC, - C(=0)-SCAC, -C(=0)-Ar, or -C(=0)-SAC-Ar, [119] [120] VII) X represents -C(=0)CH OR¹' wherein R^π is -SAC, -SCAC, -Ar, or -SAC-Ar; -C(=0)CH OC(=0)R¹² wherein R¹² is -SAC, -SCAC, -Ar, or -SAC-Ar; - CH=CH-CO 2 2 R¹³ wherein R^U is -SAC, -SCAC, -Ar, or -SAC-Ar; -CH=CH- SO R¹⁴ wherein R¹⁴ is - 2 SAC, -SCAC, -Ar, or -SAC-Ar; -C(=0)CH=CH ; or - COCH -W wherein W is -N , - 2 2 2 F, -CI, -Br, -I, -NR'⁵R'⁶ (R¹⁵ and R¹⁶ each are - SAC, -SCAC, -Ar, or -SAC-Ar, or together may form 3- to 6-membered saturated or unsaturated cyclic group), -SR 17 (R 17 is -SAC, -SCAC, -Ar, or - SAC-Ar), or is the following formula:

[121]

[122]

[123] wherein

[124] Y is H, -OH, -OR¹⁸ (R¹⁸ = -SAC or -SCAQ, -C(=0)R ^I9 (R¹⁹= -H, -SAC, or - SCAQ, -F, -CI, -Br, -I, - , -NC, -N ₃, -CO H, CF , -CO R²⁰ (R²⁰ = -SAC or -SCAQ, -C(=0)NHR ^2I (R²¹ = -SAC or -SCAQ, or -C(=0 NR ³ (R²² and R²³ each are -SAC, -SCAC, -Ar, or -SAC-Ar ), [125] R²⁴ is H, -SAC, -SAC-Ar, or -Ar.

[126] [127] The preferred compounds among the compound of formula (1) above are those wherein [128] R represents H; . 1 [129] R r reepprreesseennttss --CCFH COOH, -CH COOR (R =SAQ, or -CH CONHSO R (R = SAQ; [130] R^" represents H, -SAC, -Ar, or -(CH ) OR (R = -SAC, -SCAC, -Ar, or -SAC-Ar_: 2 n and n = 1 or 2); or [131] X represents -C(=0)CH OAr, -C(=0)CH OC(=0)Ar, or -COCH -W wherein W is 2 . 2 2 -N 2 , -F, -CI, -Br, -I, -NR¹⁵R ⁶ (R¹' and R¹ each are -SAC, -SCAC, -Ar, or -SAC-Ar, or together may form 3- to 6-membered saturated or unsaturated cyclic group), or -SR (R^π is -SAC, -SCAC, -Ar, or -SAC-Ar). [132] [133] More preferred compounds among the compound of formula (1) above are those wherein [134] I) R represents H, [135] II) R¹ represents -CH COOH, -CH COOR³ (R³=SAQ, or -CH COrøSO R⁴ (R⁴ = 2 2 2 2 SAQ, [136] III) R² represents H, -SAC, -Ar, or -(CH ) OR⁷ (R⁷ = -SAC, -SCAC, -Ar, or - SAC- 2 n Ar, and n = 1 or 2), [137] IV) A represents -(CH ) - (n = 0-4) or -0-(CH ) - (n = 0-4), 2 π 2 n

[138] V) B represents H, -SAC, -SCAC, -Ar, or -SAC-Ar,

[139] VI) X represents -COCH N , -COCH F, -COCH CI, -COCH Br, -COCH I, - COCH 2 2 2 2 2 2 OAr, -COCH OCOAr or -COCH SR^1? (R¹⁷ is -SAC, -SCAC, -Ar or -SAC-Ar). 2 2 2

[140]

[141] Particularly preferred compounds are those selected from the following group:

[142] (1) (3S)-5-[(2,6-dichtorobenzoyl)oxy] - 3-( { [5-methyl-3-phenyl-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopentanoic acid (Iaa); [143] (2) (35)-3-({[5-methyl-3-phenyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-phenoxypentanoic acid (Ibb); [144] (3) (3S)-3-({[5-ethyt3-phenyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Ice); [145] (4) (35)-3-({ [5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafiuorophenoxy)pentanoic acid (Idd); [146] (5) (3S)-3-({ [5-ethyl-3-(2-naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (lee); [147] (6) (35)-3-({[5-ethyt3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafborophenoxy)pentanoic acid (Iff); [148] (7) 3-({[5-ethyl-3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Igg); [149] ^■ (8) ethyl 3-({[5-ethyl-3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoate (Hih); [150] (9) 5-fluoro-3-({[(5R)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxopentanoic acid (Iii); [151] (10) 3-({[5-ethyl-3-(4-quindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ijj); [152] (11) 3-({[3-(benzothiophen-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ikk); [153] (12) (3S)-3-({[3-(l,3-dimethyH H-indd-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid ( II ); [154] (13) 3-({[3-(l,3-dimethyl-l H-indd-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fiuoro-4-oxopentanoic acid (Imm); [155] (14) (35)-3-( { [5-ethyl-3-( 1 -naphthylmethyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetraf iorophenoxy)pentanoic acid ( Inn ); [156] ^• (15) (35)-5-[(2,6-dichtorobenzoyl)oxy]-3-[({5-ethyl-3-[2-(l-naphthyl)ethyl] - 4,5-dihydro-5-isoxazdyl }carbonyl)amino]-4-oxopentanoic acid (loo); [157] (16) (35)-3-[({5-ethyl-3-[(l-naphthyloxy)methyl] - 4,5-dihydro-5-isoxazdyl}carbonyl)amino]-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)penta noic acid (Ipp); [158] (17) (35)-3-{ [(3-{[(4-chtoro-l-naphthyl)oxy] methyl }-5-ethyl-4,5-dihydro-5-isoxazdyl)carbonyl]amino}-4-oxo-5-(2, 3,5, 6-tetrafluor ophenoxy)pentanoic acid (Iqq); [159] (18) (3S,4£)-6-ethoxy-3-({ [(5fl )-5-isopropyl-3-(l-isoquinoBnyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-6-oxo-4- hexenoic acid (Irr); [ 160] (19) (3S,4£)-3-( { [(5 ?)-5-isopropyl-3-( 1 -isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-(methylsulfonyl)-4-pentenoic acid (Iss); [161] (20) 5-flιoro-3-({ [(5 S)-3-(l-isoquinofinyl)-5-propyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxopentanoic acid (Itt); [ 162] (21 ) 3-( { [(55)-5-ethyl-3-( 1 -naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iuu); [163] (22) 3-({[(55)-5-ethyl-3-(2-quinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ivv); [164] (23) 3-({ [(5R)-5-ethyl-3-(3-isoquindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iww); [165] (24) 3-({[5-ethyt3-(8-quincfinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ixx); [166] (25) 3-({[5-ethyl-3-(3-quindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iyy); [167] (26) 5-fluoro-3-({[(5/?)-5-isopropyl-3-(2-quindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxopentanoic acid (Izz); [168] (27) 3-({ [5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal); [169] (28) 3-[({3-[3-(tert-butyl)phenyl] - 5-ethyl-4,5-dihydro-5-isoxazdyl } carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa2); [170] (29) 3-[({3-[4-(tert-butyl)phenyl] - 5-ethyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa3); [171] (30) 5-fhιoro-3-({[(5R )-5-isopropyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxo pentanoic acid (Iaa4); [172] (31) 3-[({(5R)-3-[3-(ft?rt-butyl)phenyI] - 5-isopropyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa5); [173] (32) 3-{[(3-[l,l'-biphenyI]-3-yl-5-isopropyl-4,5-dihydro-5-isoxazdyl)carbonyl] amino }-5-fluoro-4-oxopentanoic acid (Iaa6); [174] (33) 3-({[5-ethyl-3-(2-pyridinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaa7); [175] (34) 3-[({3-[4-(tert-butyl)-2-pyridinyl] - 5-ethyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa8); [176] (35) 3-[({(5R)-3-[4-(tert-butyl)-2-pyridinyl] - 5-isopropyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa9); [177] (36) 3-({ [5-ethyt3-(4-isobutyl-2-pyridinyl)-4,5-dihydro -5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (IaalO); [178] (37) 3-({[3-(4-acetyμ2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaall); [179] (38) 3-({ [3-(4-cyctopropyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal2); [180] (39) 3-({[3-(4-cycbpentyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal3); [181] (40) 3-({[(5i?)-3-(4-cyctopentyl-2-pyridinyl)-5-isopropyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal4); [182] (41) 3-({ [3-(4-cyctohexyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal5) [183] (42) 3-([ [5-ethyl-3-(5,6,7₎8-tetrahydro-l-isoquindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaalό); [184] (43) 5-fluoro-3-({[5-isopropyl-3-(4-phenyl-2-pyridinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxopentanoic acid (Iaal7); [185] (44) (3S)-5-[(diphenylphosphoryl)oxy]-3-({[(5R )-5-isopropyl-3-( 1 -isoquinoϋnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopen tanoic acid (Iaalδ); [186] (45) (3S)-3-( { [(5Λ)-5-isopropyl-3-( 1 -isoquinoHnyl)-4,5-dihydro-5-isoxazdyl] carbonyl } amino)-4-oxo-5- { [ 1 -phenyl-3-(trifluoromethyl)- 1 H-pyrazol-5-yl] oxy}pentanoic acid (Iaal9); [187] (46) (3S)-5-[(4-benzyl-5-oxo-2₎5-dihydro-3-furanyl)oxy-3-({[(5 R )-5-isopropyl-3-( 1 -isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopen tanoic acid (Iaa20); [188] (47) (35)-5-(isobutyrytoxy)-3-( { [(5 R )-5-isopropyW-(l-isoquinoEnyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxopen tanoic acid (Iaa21); [189] (48) (35)-3-( { [(5R)-5-isopropylθ-( l-isoquinofinyI)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-hexenoic acid (Iaa22); [ 190] (49) (3S)-3-( { [(5/?)-5-isopropyl-3-( 1 -isoquincfinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2-pyridinytoxy)pentanoic acid (Iaa23); [191] (50) (3S)-3-({[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2-pyridinyloxy)pentanoic acid (Iaa24); [192] (51) 2-{[(3S)-4-carboxy-3-({[(5# )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-2-oxobut yl]oxy}-l-methylpyridinium trifluoromethanesulfonate (Iaa25); [193] (52) 2- {[(35 )-4-carboxy-3-({[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl]carbonyl}am ino)-2-oxobutyl] oxy } - 1 -methylpyridinium trifluoromethanesulfonate (Iaa26) ; [194] (53) 3-({ [3-(5-chtoro-l -methyl- 1 H - indol-2-yl)-5-isopropyl-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-5-fluoro-4-oxopent anoic acid (Iaa27); [195] (54) 3-({[3-(l,5-dimethyl-l H-indd-2-yl)-5-isopropyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaa28); and [196] (55) (3S)-5-fluoro-3-({[(5R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxopen tanoic acid (Iii-1). [197] [198] The compound of formula (1) according to the present invention has two (2) asymmetric carbon atoms, and so may exist in its stereoisomeric form including di- astereomer. Particularly preferred compounds among the stereoisomers are those having the fdtawing formula (la): [199]

[200] (la)

[201]

[202] and so it is another object of the present invention to provide the compound of formula (la) in the stereoisomeric form.

[203]

[204] Among the compound of formula (la), for example, the compound of (3 S )-5-fluoro-3-( { [(5 R)-5-isopropyl-3-( 1 -isoquindinyl)-4,5-dihydro-5- isoxazdyl] carbonyl }amino)-4-oxopentanoic acid (Iii-1) may be obtained by a process comprising the steps of dissdving a mixture of (35) and (3R) in methyl t-butyl ether, adding a smal amount of crystalline (3 S)-5-fiuoro-3-({[(5R )-5-isopropyl-3-( 1 -isoquincϊnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopen tanoic acid as a seed material to give a crystal, and recrystalzing this crystal from ethyl acetate/n-hexane sdvent system.

[205]

[206] The most preferred compounds among the compounds of formulae (1) and (la) are 5 ^■fluoro-3-({[(5/?)-5-isopropy -3-(l-isoquinolinyl)-4,5-dihydro-5- isoxazdyl] ca ιrrlbonyl}amino)-4-oxopentanoic acid (Iii); and (35)-5-fluoro-3-({[(5R )-5-isopropyl-3-( 1 -isoquincϊnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopen tanoic acid (Iii-1).

[207] [208] The processes for the preparation of the novel isoxazoline derivative of formula (1) showing an inhibitory activity against caspases are depicted in the f towing Reaction Schemes 1 to 5. However, those illustrated in the fdtawing Reaction Schemes represent only the typical processes used in the present invention. The manipulation order may be changed with no limit, and so the processes are not restricted to those explained below.

[209] [210] Reaction Scheme 1 [211] NCS HI IV

[212] in which [213] A, B, and R are defined as described above, and [214] P represents simple alkyl chain. [215] [216] In Reaction Scheme 1 above, an aldehyde derivative (II) is reacted with hydr oxylamine-hydrochtoride and sodium carbonate in a sdvent mixture of alcohol-water to give an oxime derivative (III) (a mixture of syn and and oximes). The resulting oxime derivative (III) is treated by NCS (N-chtorosuccinimide) in dimethylformamide solution to give a hydroxamoyl chloride derivative (IV). Thus obtained hydroxamoyl chloride derivative (IV) is reacted with an acrylate derivative (V) to give an isoxazoline derivative (VI), which is then hydrdyzed, if needed, to give a deprotected isoxazoline derivative (VII). If appropriate, the oxime derivative (III), the acrylate derivative (V), and NaOCl may react together in a reaction vessel (in situ) to directly give the isoxazoline derivative (VI) (see Preparations 16 and 17). [217] [218] Reaction Scheme 2 [219]

1 ) Dess-Martin 2) Deprotection if needed

l ( X = COCH2 Z ( Z= OR" , OC (=0) R¹², or VV) [220] in which A, B, R, R , R^", R , R ^", and W are defined as described above . [221] [222] In Reaction Scheme 2 above, a carboxyϋc acid derivative (VII) is coupled with an aspartic acid derivative (VIII) (see the following Reaction Scheme 3) to give a compound (IX), which is then subjected to Dess-Martin periodinane oxidation reaction, and deprotection reaction, if needed, to give the desired compound of formula (1).

[223] [224] The functional group Z in the compound (I) of Reaction Scheme 2 may be formed through several steps as exemplified in the fdtawing Preparations 5 and 7 after the carboxyϋc acid compound (VII) on the left side is combined with an aspartic acid (β-t-Bu) methylester. Otherwise, as depicted in the following Reaction Scheme 3, the compound (VIII) already having the desired Z is synthesized first and coupled with the compound (VII) (Ref.: WO 00/23421). Further, when W is F, the racemic compound may be prepared according to a method known in Tetrahedron Letters, 1994, 55(52), 9693-9696.

[225] [226] Reaction Scheme 3 [227] XII Vlll

[228] in which Z is defined as described above. [229] [230] The acrylate derivative (V) used as a reactant in the above Reaction Scheme 1 may be prepared via two (2) pathways. That is, a compound (XV) can be easily prepared from a known compound (XIV) (Synthesis, 1982, p 924) as depicted in the fdtawing Reaction Scheme 4, or methyl (ethyl) 2-i-propylacrylate, the compound (V), can be prepared from dimethyl(diethyl)matonate ( J. Chemical Society Perkin Trans. 1 1997, 1559-1570).

[231] [232] Reaction Scheme 4 [233]

[234] in which P and R' are defined as described above 1 [235] [236] The fdtawing Reaction Scheme 5 shows a synthetic process for preparing a compound wherein α,β-unsaturated ester or α,β-unsaturated sulfon is introduced into the P site. According to this, the carboxyϋc acid derivative (VII) as prepared in Reaction Scheme 1 is reacted with an amino alcohd derivative (XVII) to give a compound (XVI), which is then subjected to Dess-Martin oxidation and Wittig reactions to give the compound (I).

[237]

[238] Reaction Scheme 5

[239]

1) Dess-Martin

[240] in which I 2

[241] R, A, B, R , and R are defined as described above, and

[242] Q represents -CO R or SO R , wherein R and R are defined as described above.

[243]

[244] The compound of formula (1) according to the present invention has a broad spectrum of inhibitory activity against caspases as demonstrated by the results of the fdtawing Experiments, and so has an effect for preventing inflammation and apoptosis. Thus, the present invention provides a composition for inhibiting caspases, specificaly a therapeutic composition for preventing inflammation and apoptosis, comprising the compound of formula (1) as an active ingredient together with the pharmaceuticaly acceptable carrier. Specificaly, the composition of the present invention has a therapeutic effect for dementia, cerebral stroke, brain impairment due to AIDS, diabetes, gastric ulcer, cerebral injure by hepatitis, hepatitis-induced hepatic diseases, acute hepatitis, fulminant hepatic failure, liver cirrhosis, sepsis, organ transplantation rejection, rheumatic arthritis, or cardiac eel apoptosis due to ischemic cardiac diseases, particularly specificaly for acute hepatitis, liver cirrhosis, or rheumatic arthritis.

[245]

[246] Caspase inhibitor, particularly the compound of formula (1), may be formulated into various pharmaceutical forms for administration purpose. To prepare the pharmaceutical composition according to the present invention, an effective amount of the caspase inhibitor, particularly the compound of formula (1) or its salt, is mixed with a pharmaceuticaly acceptable carrier that may take a wide variety of forms depending on the formulation to be prepared.

[247]

[248] The caspase inhibitor compound may be formdated as a parenteral injection, or percutaneous or oral preparation depending on its application purpose. It is especialy advantageous to formdate the composition in a unit dosage form for ease of administration and uniformity of dosage.

[249]

[250] For the oral preparation, any usual pharmaceutical carrier may be used. For example, water, glycds, oils, alcohds and the like may be used for such oral liquid preparations as suspensions, syrups, elixirs and solutions; or starches, sugars, kaolin, lubricants, binders, disintegrating agents and the Hke may be used for such solid preparations as powders, pis, capsdes and tablets. Due to their ease of administration, tablets and capsules are the most advantageous dosage unit forms. It is also desirable for tablets and pis to be formdated into enteric-coated preparation.

[251]

[252] For the parenteral preparation, sterile water is usualy used as the carrier, though other ingredients such as sdubffity aids may be used. Injections, for example, sterilized aqueous or oily suspension for injection, can be prepared according to the known procedure using suitable dispersing agent, wetting agent, or suspending agent. Sdvents that can be used for preparing injections include water, Ringer's fluid, and isotonic NaCl sdution, and also sterilized fixing ofl may be conveniently used as the sdvent or suspending media. Any non-stimulative fixing oil including mono-, di- glyceride may be used for this purpose. Fatty acid such as deic acid may also be used for injections. [253]

[254] For the percutaneous administration, the carrier may include a penetration enhancing agent and/or a suitable wetting agent, optionaly combined with suitable additives having no significant skin irritation. Said additives may facilitate the administration through the skin and/or may assist preparation of a desired composition. These percutaneous preparations are administered via various manners, e.g., as a transdermal patch, a spot-on, or an ointment.

[255]

[256] When the caspase inhibitor, specificaly the compound of formda (1), is used for clnical purpose, it is preferably administered to the subject patient in an amount ranging from 0.1 to 100 mg per kg of body weight a day. The total daily dosage may be administered once or over several times. However, specific administration dosage for an individual patient can be varied with specific compound used, body weight, sex, hygienic condition, or diet of subject patient, time or method of administration, excreti on rate, mixing ratio of agent, severity of disease to be treated, etc.

[257]

[258] The present invention wi be more specificaly explained by the following examples. However, it shodd be understand that these examples are intended to illustrate the present invention but not in any manner to limit the scope of the present invention.

[259]

[260] Preparation 1

[261] Benzaldehyde oxime

[262] Benzaldehyde (5.3 lg, 50.0mmd) was dissdved in ethand (60 m-C )-water (30 m£ ), and hydroxylamine hydrochtoride (5.21g, 1.5 Eq) and anhydrous sodium carbonate (Na CO , 3.97g, 0.75 Eq) were added thereto at 0°C. When a large amount of sold was 2 3 formed after about one minute, water-ethand (1: 1, 60 mi ) was added, and the mixture was stirred for one hour. Saturated aqueous sodium chloride solution (100 m2 ) was added, and the mixture was extracted twice with ethyl acetate (300 m2 ). The extract was washed with 1.0 N aqueous sodium bicarbonate solution (NaHCO , 100 m-β x 2), 3 dried (anhydrous Na SO ), and concentrated under reduced pressure to give the title compound (6.06g, Yield 99%) as a white powder as a mixture of cis and trans.

[263] [[226644]] ' H-NMR(500MHz, CDCl ) δ 8.9(br, 1H), 8.1(s, 1H), 7.5(m, 2H), 7.3(m, 3H) [265] [266] Preparation 2

[267] Benzaldehyde hydroxamoyl chloride

[268] The oxime prepared in Preparation 1 (3.00g, 24.8mmd) was dissdved in dimethylformamide (100 mi ), and N-chtorosuccinimide (3.47g, 1.05 Eq) was added. The resdting solution was stirred for one hour in a water bath of about 40 °C, and the vdatile sdvent was removed by distlation under reduced pressure. The residue was dissdved in ethyl acetate-hexane (1:1, 150 mi ), washed with water (100 mi x 3), dried (anhydrous Na SO ), and concentrated under reduced pressure to give the title 2 4 compound (3.86g, Yield 99%). This compound was used in the next reaction without any further purification.

[269]

[270] Preparation 3

[271] Methyl 5-methyl-3-phenyl-4,5-dihydro-5-isoxazolecarboxylate (Via)

[272] The hydroxamoyl chloride prepared in Preparation 2 (3.86g, 24.8mmd) and methyl methacrylate (4.0 mi , 37.2mmd, 1.5 Eq) were dissdved in dry diethylether (120 mi ) under nitrogen atmosphere, the mixture was kept at -78 °C, and triethylamine (6.9 mi , 2.0 Eq) was added. The mixture was stirred overnight while it was slowly warmed to room temperature. Water (100 m2 ) was added, and then the mixture was extracted with ethyl acetate (100 mi x 2), washed with water (100 mi ), dried (anhydrous Na SO ), 2 4 and concentrated under reduced pressure. The residue was purified by column chro- matography (15% ethyl acetate-hexane) to give the title compound (5.34g, Yield 98%), which was then identified by H-NMR to be 1: 1 mixture of diastereomers.

[273] 1

[274] ' H-NMR(400MHz, CDC1 ) δ 6.7(m, 2H,), 6.5(m, 3H), 3.0(d, J = 16.7Hz, 1H), 2.9(s, 3H), 2.3(d, J = 16.7Hz, 1H), 0.8(s, 3H)

[275]

[276] Preparation 4

[277] 5-Methyl-3-phenyl- 4_?5-dihydro-5-isoxazolecarboxylic acid (Vila)

[278] The compound prepared in Preparation 3 (Via, 5.34g) was dissdved in distled tetrahydrofuran (120 mi ), and IN aqueous sodium hydroxide solution (36.5 mi , 1.5 Eq) was added. After about four hours, the mixture was neutralized by IN aqueous hydrochloric acid solution and distiled under reduced pressure to remove most of tetrahydrofuran. The residue was dissdved in excess ethyl acetate (>700 mi ), washed with water, dried (anhydrous Na SO ), and concentrated under reduced pressure to 2 4 give the title compound (4.77g, Yield 95%) as a white powder. This compound was used in the next reaction without any further purification. [279] [280] Preparation 5 [281] (35)-3-{[(benzyloxy)carbonyl]amino}-5-(t-butoxy)-2- hydroxy-5-oxopentyI 2,6-dichlorobenzoate (Xlla) [282] To N-benzytaxycarbonyl-β-t-butylaspartic acid (5.03g, 15.6mmd) and NMM (1.90 mi , 17.1mmd) was added dry tetrahydrofuran (60 mi ) under nitrogen atmosphere, the mixture was kept -15°C, and isobutyl chtoroformate (2.12 mi , 16.3mmd) was added thereto. The mixture was stirred for about 20 minutes. To the reaction mixture being kept at CPC was added diazomethane-ether solution (synthesized from 2.0 Eq of l-methyl-3-nitro-l-nitroso-guanidine, 60 mi ) to prepare diazoketone derivative (-30 minutes). 30% HBr/AcOH (6.42 mi , 2.0 Eq) was added thereto at 0°C. The resdting mixture was stirred (30-60 minutes), extracted with ethyl acetate, washed twice with saturated aqueous sodium bicarbonate solution and once with aqueous sodium chloride solution, dried (anhydrous Na SO ), and concentrated under reduced pressure to give bromomethyl ketone derivative (X, 6.4g).

[283]

[284] Thus obtained bromomethyl ketone derivative (X, 4.36g) and 2,6-dichtorobenzoic acid (2.28g, 1.1 Eq) were dissdved in dimethylformamide (18 mi ), KF (1.58g, 2.5 Eq) was added, and the mixture was stirred for two hours to give 2,6-dichtorobenzoytoxymethyl ketone derivative (XIa). This compound was dissdved in methand (20 mi ) and reacted by adding NaBH (412mg)-methand solution (40 mi 4 )(-lCPC~room temperature, two hours). The reaction was stopped by acetic acid, and the reaction solution was distled under reduced pressure to remove methand. The residue was extracted with ethyl acetate (50 mi x 2), washed with water and aqueous sodium chloride solution, dried (anhydrous Na SO ), concentrated under reduced 2 4 pressure, and separated-purified by column chromatography (ethyl acetate-hexane, 1:5) to give the title compound (4.80g, Yield 86%) in a diastereomeric form. [285] [286] ' H-NMR (400 MHz, CDC1 ) δ 7.3-7.2(m, 8H), 5.9(m, 1H), 5.2(m, 4H), 4.7(m, 1H), 2.9(m, 1H), 2.7(m, 1H), 1.4(s, 9H) [287]

[288] Preparation 6

[289] (3-S)-3-amino-5-(t-butoxy)-2-hydroxy-5-oxopentyl 2,6-dichlorobenzoate (Vina) [290] The benzytoxycarbonyl group of the compound prepared in Preparation 5 was removed (Pd/Q under hydrogen balloon for 40 minutes to give the title compound (Yield 100%).

[291]

[292] ' H-NMR (400 MHz, DMSO-d 6 ) δ 8.2(br, 2H), 7.6-7.5(m, 3H), 6.1(m, 1H), 4.4-3.9(m, 3H), 3.0-2.6(m, 2H), 1.4(s, 9H)

[293]

[294] Example 1

[295] (35)-5-(^-butoxy)-3-{[(5-methyl-3-phenyl-4,5-dihydro-5-isoxazolyl)carbonyl] amino}-2,5-dioxopentyI 2,6-dichlorobenzoate (la)

[296] A mixture of the carboxyKc acid derivative prepared in Preparation 4 (Vila, 300mg, 1.46 mmd), the amino alcohd derivative prepared in Preparation 6 (Villa, 667 mg, 1.1 Eq) and HATU (722mg, 1.3 Eq) was coded to CPC, triethylamine (0.82 mi , 4.0 Eq) was added in a sdvent of DMF(5 mi ), and the resdting mixture was reacted for 5 hours. The sdvent was distled under reduced pressure, and the residue was extracted with ethyl acetate (200 mi x 2), washed with water, aqueous sodium bicarbonate solution, and aqueous sodium chloride solution, dried (anhydrous Na SO ), con- 2 4 centrated under reduced pressure, and purified by column chromatography to give Compound (IXa) (810mg, Yield 98%). To this compound and Dess-Martin reagent (1.70g, 3.0 Eq) was added dry dichtoromethane (25 mi ), and the mixture was stirred for one hour at room temperature. The reaction was stopped by isopropyl alcohd (3 mi ). The solid was removed by filtration under reduced pressure through Cefite, and the filtrate was extracted with ethyl acetate (20 mi x 2), washed with water, saturated aqueous sodium bicarbonate solution and aqueous sodium chloride solution, dried (anhydrous Na SO ), concentrated under reduced pressure, and preliminarily purified by column chromatography (36% ethyl acetate-hexane) to give the diastereomeric title compound (780 mg).

[297]

[298] ' H-NMR(400MHz, CDC1 ) δ 7.8(m, Hi, 1H), 7.6(m, 2H), 7.3(m, 3H), 7.2(m, 3H), 5.1-5.0(m, 2H), 4.8(m, 1H), 3.8(m, 1H), 3.2(m, 1H), 2.9-2.8(m, 2H), 1.7(s, 3H), 1.4(s, 9H)

[299]

[300] Example 2

[301] (35)-5-[(2,6-dichlorobenzoyI)oxy] - 3-{[(5-methyl-3-phenyl-4,5-dihydro-5-isoxazolyl)carbonyl]amino}-4-oxopentanoic acid (Iaa)

[302] The compound prepared in Example 1 (44 mg) was dissdved in dichtoromethane (2 mi ), and trifluoroacetic acid (1 11 ) was added at CPC. The mixture was stirred for two hours while it was slowly warmed to room temperature, and then concentrated under reduced pressure to give the title compound (Iaa) in a stoichiometric amount.

[303]

[304] ' H-NMR(500MHz, CDC1 ) δ 8.1(m, 1H), 7.5((m, 2H), 7.3(m, 3H), 7.2(m, 3H), 5.1-4.9(m, 2H), 4.9-4.8(m, 1H), 3.8(m, 1H), 3.2(m, 1H), 1.7(m, 3H)

[305]

[306] Preparation 7

[307] t -Butyl (35)-3-amino-4-hydroxy-5-phenoxypentanoate (VHIb)

[303] To N-benzytoxycarbonyl-β-t-butyl-aspartic acid (10.0 g, 31.0 mmd) and NMM (3.75 mi , 1.1 Eq) was added dry tetrahydrofuran (120 ml ) under nitrogen atmosphere, and the mixture was kept at -15°C. Isobutyl chbro formate (4.22 mi , 1.05 Eq) was added thereto, and the mixture was stirred for about 20 minutes. The reactants were kept at CPC, which was then mixed with diazomethane-ether solution (synthesized from 2.0 Eq of l-methyl-3-nitro-l-nitrosoguanidine, 60 mi ) to prepare diazoketone derivative (-30 minutes). 30% HBr/AcOH (12.83 mi , 2.0 Eq) was added thereto to prepare bromomethyl ketone derivative (30-60 minutes)., he product was extracted with ethyl acetate, washed twice with saturated aqueous sodium bicarbonate solution and aqueous sodium chloride solution, dried (anhydrous Na SO ), and concentrated 2 4 under reduced pressure to give bromomethyl ketone derivative (12.9 g) in a stoichiometric amount.

[309]

[310] Thus obtained bromomethyl ketone derivative (X, 12.9g, 31.Ommd) and phend (3.23g, 1.2 Eq) were dissdved in dimethylformamide (30 mi ), KF(4.53g, 2.5 Eq) was added, and the mixture was stirred for two hours to give phenoxymethyl ketone derivative (Xlb). This compound was dissdved in methand (40 mi )-THF (100 mi ) and was reacted by adding NaBH (2.35 g)-methand solution (40 mi ) (-lCPC-room 4 temperature, two hours). The reaction was stopped by acetic acid, and the reaction mixture was distilled under reduced pressure to remove methand. The residue was extracted with ethyl acetate (50 mi x 2), washed with water and aqueous sodium chloride solution, dried (anhydrous Na SO ), concentrated under reduced pressure, and 2 4 separated-purified by column chromatography (ethyl acetate-hexane, 1 :7) to give a compound (Xllb, 6.50g, Yield 50%) in a diastereomeric form of which amino group is protected by benzytoxycarbonyl. [311] [312] ' H-NMR(400 MHz, CDC1 ) δ 7.3-7.2(m, 8H), 5.9(m, 1H), 5.2(m, 4H), 4.7(m, 1H), 2.9(m, 1H), 2.7(m, 1H), 1.4(s, 9H) [313] [314] The benzytoxycarbonyl group of the compound obtained above was removed (Pd/Q under hydrogen batoon to give the title compound (4.16g, Yield 95%). [315] t

[316] H-NMR(400MHz, DMSO-d ) δ 8.1(br, 2H), 7.3(m, 5H), 5.6(m, 1H), 4.1-4.0 (m, 3H), 2.6(m, 2H), 1.4(s, 9H)

[317]

[318] Example 3

[319] t-butyl (35)-3-{[(5-methyl-3-phenyl-4,5-dihydro-5-isoxazolyI)carbonyl] amino}-4-oxo-5-phenoxypentanoate (lb)

[320] A mixture of the carboxyϋc acid derivative prepared in Preparation 4 (Vila, 273 mg, 1.33 mmd), the amino alcohd derivative prepared in Preparation 7 (VHIb, 412 mg, 1.1 Eq) and HATU (657 mg, 1.3 Eq) was coded to CPC, triethylamine (0.74 mi , 4.0 Eq) was added in a sdvent of DMF(5 mi ), and the resdting mixture was reacted for 5 hours. The sdvent was distffled under reduced pressure, and the residue was extracted with ethyl acetate (200 mi x 2), washed with water, aqueous sodium bicarbonate solution, and aqueous sodium chtoride solution, dried (anhydrous Na SO ), 2 4 concentrated under reduced pressure, and purified by cdumn chromatography (30-40% EA/Hex) to give Compound (IXb) (545 mg, Yield 88%). To this compound and Dess-Martin reagent (1.43 g, 3.0 Eq) was added dry dichtoromethane (25 mi ), and the mixture was stirred for one hour at room temperature. The reaction was stopped by isopropyl alcohd (2 mi ). The solid was removed by filtration under reduced pressure through CeHte, and the filtrate was extracted with ethyl acetate (20 mi x 2), washed with water, saturated aqueous sodium bicarbonate solution and aqueous sodium chtoride solution, dried (anhydrous Na SO ), concentrated under reduced pressure, and preliminarily purified by column chromatography (eluent: 25% ethyl acetate-hexane) to give the diastereomeric title compound (540 mg, Yield 99%).

[321]

[322] H-NMR(400MHz, CDC1 ) δ 7.8(rø, 1H), 7.5(m, 2H), 7.3(m, 3H), 7.3(m, 1H), 3 7.1(m, 1H), 6.8(m, 2H), 6.7(m, 1H), 4.9(s, 1H), 4.7-4.6(m, 2H), 3.7(d, J = 17Hz, 1H), 3.2(d, J = 17Hz, 1H), 2.9(m, 1H), 2.8(m, 1H), 1.7(s, 3H), 1.4(s, 9H) [323]

[324] Example 4

[325] (35)-3-{[(5-methyl-3-phenyl-4,5-dihydro-5-isoxazolyl)carbonyl] amino}-4-oxo-5-phenoxypentanoic acid (Ibb)

[326] The compound prepared in Example 3 (530 mg, 1.136 mmd) was dissdved in dichtoromethane (6 mi ), and trifiuoroacetic acid (3 mi ) was added at CPC. The mixture was stirred for two hours while it was slowly warmed to room temperature, and concentrated under reduced pressure to give the title compound (Ibb) (465 mg) with a stoi- chiometric yield.

[327]

[328] ' H-NMR(400MHz, CDC1 ) δ 7.5(m, 2H), 7.3(m, 3H), 7.1( H, 1H), 6.7(m, 5H), 5.0-4.6(m, 2H), 4.2(m, 1H), 3.8(m, 1H), 3.2(m, 1H), 3.0-2.7(m, 2H), 1.6(s, 3H)

[329]

[330] Preparation 8

[331] Ethyl 2-ethylacrylate (XVb)

[332] To CuCN (26.9 g, dried in advance under vacuum) was added under nitrogen atmosphere about 500 mi of dry tetrahydrofuran. The mixture was kept at -78^, and 100 mi of methyl magnesium bromide (3.0M diethylether solution) was stowly added thereto under mechanical stirring. The thick mixture was stirred for about 30 minutes at -78X1 Ethyl 2-bromomethylacrylate (28.9 g, 150 mmd, Synthetic method: Vieras, J. and Rambaud, M. Synthesis, 1982, 914) dissdved in about 30 mi of dry tetrahydrofuran was stowly added thereto. The temperature of the reaction mixture was stowly raised to room temperature over two hours. The reaction was completed by stowly adding saturated ammonium chtoride solution (-50 mi ). The reaction mixture was filtered through Ceϋte to remove the precipitates, and then washed with diethylether. The organic layer was washed with water and saturated sodium bicarbonate solution (300 mi x 2), dried (anhydrous Na SO ), and concentrated under reduced 2 4 pressure to give 26.7g (stoichiometric yield) of a transparent liquid. This liquid was identified by H-NMR (500 MHz, CDCl ) and was confirmed to be the title compound having about 75% of w/w purity. [333] [334] ' H-NMR(500MHz, CDCl ) δ 6.12(1H, s), 5.50(1H, s), 4.20(2H, q, J = 7.3 Hz), 2.31(2H, qt), 1.28(3H, t, J = 7.3 Hz), 1.07(3H, t, J = 7.8Hz) [335] [336] Preparation 9 [337] Ethyl 5-ethyl-3-phenyl-4,5-dihydro-5-isoxazolecarboxylate (VIb) [338] The compound of Preparation 8 (XVa) was reacted according to the same procedure as Preparation 3 to give the title compound. [339] [340] ' H-NMR(400MHz, CDCl ) δ 7.6(m, 2H), 7.4-7.3(m, 3H), 4.3-4.2(m, 2H), 4.0(d, J = 17.2Hz, IH), 3.4(d, J=17.2Hz, IH), 2.1-2.0(m, 2H), 1.3(t, 3H), 1.0(t, 3H) [341] [342] Preparation 10 [343] t -Butyl (35)-3-amino-4-hydroxy-5-(2,3,5,6-tetrafluorophenoxy) pentanoate (VHIc) [344] 2,3,5,6-Tetrafluorophend was reacted according to the same procedure as Preparations 5 and 6 to give the title compound in a total yield of 72%. [345] [346] ' H-NMR(400MHz, DMSO-d^ δ 8.2(br, 2H), 7.6-7.5(m, IH), 5.9(m, IH), 4.3-4.1(m, 3H), 3.6(m, IH), 2.7(m, IH), 1.4(s, 9H) [347]

[348] Example 5

[349] t -Butyl (35)-3-{[(5-ethyl-3-phenyl-4,5-dihydro-5-isoxazoIyl)carbonyl] amino}-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoate (Ic) [350] The compounds of Preparations 9 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound. [351]

[352] ' H-NMR(400MHz, CDCl ) δ 7.6(dd, J = 3.6, 1.6Hz, IH), 7.6(m, 2H), 7.4- 7.3(m, 3H), 6.7(m, IH), 5.1-4.9(m, 2H), 4.9-4.8(m, IH), 3.7(dd, J = 17.6, 17.2Hz, IH), 3.3(1H, d, J = 17.2Hz), 3.0-2.8(m, IH), 2.8-2.7(m, IH), 2.1(m, IH), 1.9(m, IH), 1.4-1.3(two s, 9H,), 1.0(m, 3H) [353]

[354] Example 6

[355] (35 3-{[(5-ethyl-3-phenyl-4,5-dihydro-5-isoxazolyI)carbonyl] amino}-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Ice) [356] The compound of Example 5 was reacted according to the same procedure as Example 2 to give the title compound. [357]

[358] * H-NMR(400MHz, DMSO-d^ δ 7.6(br, IH), 7.6-7.5(m, 2H), 7.4-7.3(m, 3H), 6.8-6.7(m, IH), 4.9-4.8(m, IH), 4.5(br, 2H), 3.7(d, J = 16Hz, IH), 3.3(d, J = 16Hz, 1H), 3.3-3.0(m, IH), 2.8-2.7(m, 1H), 2.1(m, IH), 2.0-1.9(m, 1H), 1.0(m, 3H) [359] MS [M+H] ⁺ 497

[360]

[361] Preparation 11

[362] Ethyl 5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazolecarboxylate (Vic)

[363] 1-Naphthaldehyde and ethyl 2-ethylacrylate were reacted according to the same procedure as Preparations 1, 2, and 3 to give the title compound. [364] [365] ' H-NMR(400MHz, CDCl ) δ 8.9(d, J = 8.8Hz, IH), 7.9-7.8(m, 2H), 7.6- 7.4(m, 3 4H), 4.3-4.2(m, 2H), 4.0(d, J = 17.2Hz, IH), 3.4(d, J = 17.2Hz, IH), 2.1-2.0(m, 2H), 1.3(t, 3H), 1.0(t, 3H) [366]

[367] Example 7

[368] t -Butyl (35)-3-({[5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazoIyI] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoate (Id) [369] The compounds of Preparations 11 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound.

[370] 1

[371] ' H-NMR(400MHz, CDCl ) δ 8.9(m, IH), 7.9-7.8(m, 3H), 7.6-7.4(m, 4H), 6.5-6.9(m, IH), 5.1-4.9(m, 2H), 4.9(m, IH), 3.9(dd, IH), 3.5(d, J = 17.2Hz, IH), 3.0-2.9(m, IH), 2.8(m, IH), 2.2(m, IH), 2.0(m, IH), 1.4-1.3(two s, 9H), l.l(m, 3H)

[372]

[373] Example 8

[374] (35)-3-([[5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetra fluorophenoxy)pentanoic acid (Idd)

[375] The compound of Example 7 was reacted according to the same procedure as Example 2 to give the title compound.

[376] 1

[377] ' H-NMR(400MHz, CDCl ) δ 8.8(m, IH), 7.9-7.7(m, 3H), 7.6-7.4(m, 4H), 6.7 (m, IH), 4.9(m, IH), 4.5(br, 2H), 3.9(d, J = 17.2Hz, IH), 3.5(d, J = 17.2Hz, IH), 3.1-2.9(m, IH), 2.8-2.7(m, IH), 2.2(m, IH), 2.0(m, IH), 1.0(m, 3H)

[378] MS [M+MeOH+Na] ⁺.601

[379]

[380] Preparation 12

[381] Ethyl 5-ethyl-3-(2-naphthyl)-4,5-dihydro-5-isoxazoIecarboxylate (VId) [382] 2-Naphthaldehyde and ethyl 2-ethylacrylate were reacted according to the same procedure as Preparations 1, 2, and 3 to give the title compound. [383] [384] ' H-NMR(500MHz, CDCl ) δ 8.7(d, J = 8.8Hz, IH), 7.8-7.7(m, 2H), 7.5-7.3 (m, 4H), 4.3-4.2(m, 2H), 4.0(d, J = 17.2Hz, IH), 3.4(d, J = 17.2Hz, IH), 2.1- 2.0(m, 2H), 1.3(t, 3H), 1.0(t, 3H) [385] [386] Example 9 [387] t -Butyl (35)-3-({[5-ethyl-3-(2-naphthyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoate (le) [388] The compounds of Preparations 12 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound_. [389] [390] ' H-NMR(400MHz, CDCl ) δ 7.8-7.7(m, 6H), 7.5(m, 2H), 6.7 & 6.5 (m, IH), 5.1-4.9(m, 2H), 4.9-4.8(m, 2H), 3.8(dd, J = 16Hz, IH), 3.4(d, J = 16Hz, IH), 3.0(m, IH), 2.8(m, IH), 2.8-2.7(m, IH), 2.2-2. l(m, IH), 2.0(m, IH), 1.4-1.3 (two s, 9H), l.l-1.0(m, 3H) [391]

[392] Example 10

[393] (35)-3-({[5-ethyl-3-(2-naphthyI)-4,5-dihydro-5-isoxazolyI] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetra fluorophenoxy)pentanoic acid (lee) [394] The compound of Example 9 was deprotected according to the same procedure as Example 2, and the isomers were resdved by prep-TLC to give the following two compounds. [395]

[396] Weakly pdar diastereomer:

[397] ' H-NMR(400MHz, DMSO-d ) δ 12.4(br, IH), 8.7(br, IH), 8.1(s, IH), 7.9- 8.0(m, 3H), 7.8-7.9(m, IH), 7.5-7.6(m, 3H), 5.2(br, 2H), 4.7(br, IH), 3.8(d, J = 17.2Hz, IH), 3.5(d, J = 17.6Hz, IH), 2.7(m, IH), 2.5(m, IH), 2.0(m, IH), 1.9(m, IH), 0.9-0.8(m, 3H) [398] MS [M+H]⁺ 547

[399]

[400] Highly pdar diastereomer:

[401] ' H-NMR(400MHz, DMSO-d ) δ 8.6(br, IH), 8.2(s, IH), 8.0-7.9(m, 3H), 7.9(m, IH), 7.6(m, 2H), 7.4(m, IH), 5.0(br, 2H), 4.8(m, IH), 3.9(d, J = 17.6Hz, IH,), 3.6(d, J = 17.6Hz, IH,), 2.9-2.7(m, 2H), 2.1-2.0(m, IH), 2.0-1.9(m, IH), 0.9(m, 3H) [402]

[403] Preparation 13

[404] Ethyl 5-ethyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolecarboxylate (Vie)

[405] l-Isoquinofinealdehyde and ethyl 2-ethylacrylate were reacted according to the same procedure as Preparations 1, 2 and 3. The title compound in an active chiral isomeric form was separated by Chiral OD HPLC (Daicel Chemicd Industries, 2.00cm x 25cm, OD00CJ-1C005, 3% i-PrOH in Hexane, 220nm), which was then used in the next reaction. [406] [407] ' H-NMR(400MHz, CDCl ) δ 9.25(m, IH), 8.55(d, IH), 7.85(d, IH), 7.74- 7.65(m, 3H), 4.29(m, 2H), 4.13(d, IH), 3.71(d, IH), 2.1 l(m, 2H), 1.33(t, 3H), 1.06(t, 3H) [4C8]

[409] Example 11

[410] t -Butyl (35)-3-({[5-ethyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyI] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoate (If) [411] The compounds of Preparations 13 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound. [412] 1

[413] ' H-NMR(400MHz, CDCl ) δ 9.14(m, IH), 8.53(m, IH), 7.91-7.85(m, 2H), 7.74-7.64(m, 3H), 6.73-6.62(m, IH), 5.30-4.91(m, 3H), 4.09(two d, IH), 3.72(two d, IH), 3.04-2.76(m, 2H), 2.24(m, IH), 2.04(m, IH), 1.45 & 1.35(two s, 9H), l.C8(two t, 3H)

[414]

[415] Example 12

[416] (35)-3-({[5-ethyl-3-(l-isoquinolinyI)-4,5-dihydro-5-isoxazolyI] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Iff)

[417] The compound of Example 11 was reacted according to the same procedure as Example 2 to give the title compound.

[418]

[419] ' H-NMR(400MHz, DMSO-d ) δ 9.02(m, IH), 8.76(m, IH), 8.59(m, IH), 8.03-7.73(m, 4H), 7.61-7.32(m, IH), 5.19-5.10(m, 2H), 4.93-4.65(m, IH), 3.91 (two d, IH), 3.68(two d, IH), 2.91-2.52(m, 2H), 2.10-1.94(m, 2H), 0.94(two t, 3H)

[420] Mass : M+H 548

[421] [422] Example 13

[423] f-Butyl 3-({[5-ethyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoate (Ig)

[424] The compound of Preparation 13 and t-buryl 3-amino-5-fluoro-4-hydroxypentanoate were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound.

[425] 1

[426] H-NMR(400MHz, CDCl ) δ 9.15(m, IH), 8.55(d, IH), 7.87-7.66(m, 5H), 5.22-4.89(m, 3H), 4.12(two d, IH), 3.72(two d, IH), 3.05-2.75(m, 2H), 2.22 (m, IH), 2.04(m, IH), 1.45 & 1.34(two s, 9H), 1.07(two t, 3H) [427]

[428] Example 14

[429] 3-({[5-Ethyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyI] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Igg) [430] The compound of Example 13 was reacted according to the same procedure as Example 2 to give the title compound. [431]

[432] ' H-NMR(400MHz, DMSO-d ) δ 9.03(m, IH), 8.67-8.59(m, 2H), 8.C8(d, IH), 7.97-7.78(m, 3H), 5.26-5.07(m, 2H), 4.75(m, IH), 3.94(two d, IH), 3.67(two d, IH), 2.88-2.58(m, 2H), 2.07-1.94(m, 2H), 0.96(two t, 3H) [433] Mass : M+H 402

[434]

[435] Example 15

[436] Ethyl 3-({[5-ethyI-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazoIyl] carbonyl}amino)-5-fluoro-4-oxopentanoate (Ihh) [437] The compound of Example 14 was reacted according to a method known in Tetrahedron Letters, 1994, 55(52), 9693-9696 to give the title compound. [438] [439] ' H-NMR(400MHz, CDCl ) δ 9.15(m, IH), 8.55(d, IH), 7.89-7.67(m, 5H), 5.23-4.94(m, 3H), 4.18(m, 2H), 4.1 l(two d, IH), 3.72(two d, IH), 3.03-2.82 (m, 2H), 2.22(m, IH), 2.05(m, IH), 1.29-1.04(m, 6H) [440]

[441] Preparation 14

[442] Methyl 5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolecarboxylate) and resolution (Vlf) [443] 1-IsoquinoHnealdehyde and methyl 2-isopropylacrylate were reacted according to the same procedure as Preparations 1, 2 and 3 to give the title compound. From thus obtained compound, (5i?)-active chiral isomer (9.7min-11.7min) was separated by prep-HPLC using chiral OD column (Daicel Chemical Industries, 2.00cm x 25cm, OD00CJ-1C005, 5% i-PrOH in Hexane, 14 mi /min, 220nm) (the other (5S)-isomer was eluted during the retention time of 15.3-20. Imin), which was then used in the next reaction (see Preparation 23 for the resolution after hydrdysis)

[444]

[445] ' H-NMR(500MHz, CDCl ) δ 9.24(m, IH), 8.55(d, IH), 7.85(d, IH), 7.72(t, 3H), 7.67(m, 2H), 4.1 l(d, IH), 3.83(s, 3H), 3.74(d, IH), 2.50(septet, IH), 1.07(d, 3H), 1.02(d, 3H)

[446]

[447] Example 16

[448] t -Butyl 5-fluoro-3-({[(5i? )-5-isopropyl-3-(l-isoquinolinyI)-4,5-dihydro-5-isoxazolyI]carbonyl}amino)-4-oxo pentanoate (Ih)

[449] The compound of Preparation 14 and t-butyl 3-amino-5-fluoro-4-hydroxypentanoate were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound.

[450]

[451] H-NMR(500MHz, CDCl ) δ 9.14(m, IH), 8.55(d, IH), 7.87-7.65(m, 5H), 5.23-4.93(m, 2H), 4.90(m, IH), 4.05-4.00(two d, IH), 3.84-3.79(two, IH), 3.06-2.74(m, 2H), 2.40(m, IH), 1.45 & 1.34(two s, 9H), 1.12-1.07(m, 6H) [452]

[453] Example 17

[454] 5-Fluoro-3-({[(5/?)-5-isopropyl-3-(l-isoquinolinyI)-4,5-dihydro-5-isoxazolyl] carbonyI}amino)-4-oxopentanoic acid (Iii) [455] The compound of Example 16 was reacted according to the same procedure as Example 2 to give the title compound (the compound of (5 S)-isomer, Iii-u, was obtained according to the same procedure).

[456] 1

[457] H-NMR(400MHz, DMSO-d ) δ 9.00(m, IH), 8.63-8.48(m, 2H), 8.C8(d, IH), 6 7.97(m, IH) 7.87-7.76(m, 2H), 5.31-4.82(br, 2H), 4.74(m, IH), 3.91(two d, IH), 3.73(two d, IH), 2.88-2.61(m, 2H), 2.33(m, IH), 0.98(m, 6H) [458] Mass : M+H 416 [459]

[460] Preparation 15

[461] Ethyl 5-ethyl-3-(4-quinolinyl)-4,5-dihydro-5-isoxazolecarboxylate (VIg)

[462] 4-Quinoϊnealdehyde and ethyl 2-ethylacrylate were reacted according to the same procedure as Preparations 1, 2, and 3 to give the title compound.

[463] 1

[464] H-NMR(400MHz, CDCl ) δ 8.95(d, IH), 8.89(m, IH), 8.11(d, IH), 7.83(m, IH), 7.71(m, IH), 7.65(d, IH), 4.27(m, 2H), 4.01(d, IH), 3.67(d, IH), 2.10 (m, 2H), 1.31(t, 3H), 1.02(t, 3H) [465]

[466] Example 18

[467] t -Butyl 3-({[5-ethyl-3-(4-quinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyI}amino)-5-fluoro-4-oxopentanoate (Ii) [468] The compound of Preparation 15 and t-butyl 3-amino-5-fhιoro-4-hydroxypentanoate were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound.

[469] 1

[470] H-NMR(400MHz, CDCl ) δ 8.97(d, IH), 8.89(m, IH), 8.17(d, IH), 7.87-7.64(m, 3H), 7.36(d, IH), 5.21-4.93(m, 3H), 3.93(two d, IH), 3.48(two d, IH), 3.05-2.78(m, 2H), 2.24(m, IH), 2.03(m, IH), 1.46 & 1.33(two s, 9H), 1.06(two t, 3H)

[471]

[472] Example 19

[473] 3-({[5-EthyI-3-(4-quinolinyl)-4,5-dihydro-5-isoxazoIyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ijj)

[474] The compound of Example 18 was reacted according to the same procedure as Example 2 to give the title compound.

[475]

[476] ' H-NMR(400MHz, DMSO-d 6 ) δ 9.16-9.10(m, 2H), 8.25-7.86(m, 5H), 5.20(br, 2H), 4.75(m, IH), 4.00-3.89(two d, IH), 3.73(two d, IH), 2.87-2.71(m, 2H), 2.26-2.05(m, 2H), 1.07(two t, 3H) [477] Mass : M+H 402

[478]

[479] Preparation 16

[480] Ethyl 3-(benzothiophen-2-yI)-5-ethyI-4,5-dihydro-5-isoxazolecarboxylate (Vlh) [481] Benzothiophen-2-aldehyde oxime derivative (400 mg, 2.26 mmd) prepared according to the same procedure as Preparation 1 was dissdved in THF (25 mi ), and the mixture was kept at (PC. Ethyl 2-ethylacrylate (434 mg, 1.5 Eq) and triethylamine (7 drops) were dissdved in THF (5 mi ), thus obtained solution was stowly added to the above, and sodium hypochtorite solution (6.0 mi ) was further added. The reaction solution was warmed to room temperature and stirred for 4 hours. Water (20 mi ) was added, and the mixture was extracted with ethyl acetate (40 mi x 2), washed with aqueous sodium chtoride solution (20 mi ), dried over magnesium sdfate, filtered, and concentrated under reduced pressure. The residue was purified by column chromatography (20% ethyl acetate-hexane) to give the title compound (121 mg, Yield 18%).

[482] I

[483] ' H-NMR(400MHz, CDCl ) δ 7.82-7.75(m, 2H), 7.40-7.32(m, 3H), 4.28(m, 2H), 3.90(d, IH), 3.31(d, IH), 2.07(m, 2H), 1.33(t, 3H), 1.01(t, 3H) [484]

[485] Example 20

[486] t -Butyl 3-({[3-(benzothiophen-2-yI)-5-ethyI-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoate (Ij) [487] The compound of Preparation 16 and t-butyl 3-amino-5-flιoro-4-hydroxypentanoate were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound. [488] [489] ' H-NMR(400MHz, CDCl ) δ 7.83-7.68(m, 3H), 7.42-7.35(m, 3H), 5.21-4.88 (m, 3H), 3.80(two d, IH), 3.38(two d, IH), 3.03-2.78(m, 2H), 2.17(m, IH), 2.01(m, IH), 1.46 & 1.38(two s, 9H), 1.03(two t, 3H) [490]

[491] Example 21

[492] 3-({[3-(benzothiophen-2-yl)-5-ethyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (3-({ [3-(benzothiophen-2-yl)-5-ethyl-4,5- dihydro-5-isoxazoIyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid) (Ikk) [493] The compound of Example 20 was reacted according to the same procedure as Example 2 to give the title compound. [494] [495] ' H-NMR(400MHz, DMSO-dj) δ 8.63(m, IH), 8.1 l-7.79(m, 3H), 7.47-7.36(m, 2H), 5.24-5.06(m, 2H), 4.73(m, IH), 3.79(two d, IH), 3.53(two d, IH), 2.83-2.58(m, 2H), 2.03-1.86(m, 2H), 0.91 (two t, 3H)

[496] Mass : M+H 407

[497]

[498] Preparation 17

[499] Ethyl 3-(l,3-dimethyl-lfiT-indoI-2-yl)-5-ethyl-4,5-dihydro-5- isoxazole- carboxylate (Vli)

[500] l,3-Eimethyl-lH-indol-2-aldehyde oxime derivative (356 mg, 2.07 mmd) was dissdved in dichtoromethane (20 mi ), and the mixture was kept at CPC. Ethyl 2-ethylacrylate (345 mg, 1.3 Eq) and triethylamine (6 drops) were dissdved in dichtoromethane (5 mi ), thus obtained solution was stowly added to the above, and sodium hypochtorite solution (5.5 mi ) was further added. The reaction solution was warmed to room temperature and stirred for 4 hours. Water (20 mi ) was added, and the mixture was extracted with dichtoromethane (40 mi x 2), washed with aqueous sodium chloride solution (20 mi ), dried over magnesium sdfate, filtered, and concentrated under reduced pressure. The residue was purified by column chromatography (15% ethyl acetate-hexane) to give the title compound (230 mg, Yield 35%).

[501] 1

[502] ' H-NMR(400MHz, CDCl ) δ 7.60(d, IH), 7.31(m, 2H), 7.12(m, IH), 4.29(m, 2H), 3 3.98(d, IH), 3.94(s, 3H), 3.40(d, IH), 2.47(s, 3H), 2.C6(m, 2H), 1.34(t, 3H), 1.04(t, 3H) [503] Mass : M+H 315

[504]

[505] Example 22

[506] t -Butyl (35)-3-({[3-(l,3-dimethyI-lfiT-indol-2-yl)-5-ethyl-4,5-dihydro-5- isoxazolyl]carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoate (Ik) [507] The compounds of Preparations 17 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound. [5C8]

[509] ' H-NMR(400MHz, CDCl ) δ 7.85-7.79(m, IH), 7.57(m, IH), 7.37-7.26(m, 2H), 3 7.13(m, IH), 6.75-6.49(m, IH), 5.12-4.90(m,3H), 3.95(two d,lH), 3.89 (two s,3H), 3.45(two d ,1H), 3.03-2.79(m, 2H), 2.44(two s, 3H), 2.22(m, IH), 2.01(m, IH), 1.58 & 1.37(two s, 9H), 1.05(two t, 3H)

[510]

[511] Example 23 [512] (35)-3-({[3-(l,3-dimethyl-lH^r-indol-2-yl)-5-ethyl-4,5-dihydro-5-isoxazoIyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid ( 111 )

[513] The compound of Example 22 was reacted according to the same procedure as Example 2 to give the title compound. [514] [515] ' H-NMR(400MHz, DMSO-d ) δ 8.67(br, IH), 7.61-7.43(m, 3H), 7.27(m, IH), 6 7.C8(m, IH), 5.20(br, 2H), 4.83(m, IH), 3.84(two s,3H), 3.76(two d, IH), 3.59(two d ,1H), 2.91-2.60(m, 2H), 2.50(two s, 3H), 2.07-1.91(m, 2H), 0.95(two t, 3H) [516]

[517] Example 24

[518] t -Butyl 3-({[3-(l,3-dimethyl-LH^r-indol-2-yl)-5-ethyl-4,5-dihydro-5-isoxazolyl ]carbonyl}amino)-5-fluoro-4-oxopentanoate (II) [519] The compound of Preparation 17 and t-butyl 3-amino-5-fluoro-4-hydroxypentanoate were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound. [520] [521] ' H-NMR(400MHz, CDCl ) δ 7.79(m, IH), 7.60(m, IH), 7.32(m, 2H), 7.13(m, IH), 5.20-4.90(m,3H), 3.97-3.89(m, 4H), 3.46(two d, IH), 3.03-2.77(m, 2H), 2.21(m, IH), 2.01(m, IH), 1.46 & 1.38(two s, 9H), 1.05(two t, 3H) [522]

[523] Example 25

[524] 3-({[3-(l,3-Dimethyl-li -indol-2-yI)-5-ethyI-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Imm) [525] The compound of Example 24 was reacted according to the same procedure as Example 2 to give the title compound. [526] [527] ' H-NMR(400MHz, DMSO-d_g) δ 8.68(br, IH), 7.60(m, IH), 7.45(m, IH), 7.26(m, IH), 7.07(m, IH), 5.20(br, 2H), 4.81(m, IH), 3.84(two s, 3H), 3.76 (two d, IH), 3.59(two d, IH), 2.94-2.59(m, 2H), 2.38(two s, 3H), 2.07-1.91 (m, 2H), 0.95(two t, 3H) [528] Mass : M+H 418

[529]

[530] Preparation 18

[531] Ethyl 5-ethyl-3-(l-naphthylmethyl)-4,5-dihydro-5-isoxazolecarboxyIate (VIj) [532] 1-Naphthylacetaldehyde and ethyl 2-ethylacrylate were reacted according to the same procedure as Preparations 1, 2, and 3 to give the title compound. [533] 1 [534] H-NMR(500MHz, CDCl ) δ 8.1-8.0(d, J = 8Hz, IH), 7.8(d, J = 7.6Hz, IH,), 7.8-7.7(d, J = 8Hz, IH), 7.5-7.4(m, 2H), 7.4-7.3(m, 2H), 4.1-4.0(m, 4H), 3.1(d, J = 17.6Hz, IH), 2.6(d, J = 17.6Hz, IH), 1.8-1.7(m, 2H), 1.2(t, 3H), 0.7(t, 3H) [535] [536] Example 26 [537] t -Butyl (35)-3-({[5-ethyl-3-(l-naphthylmethyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafiuorophenoxy)pentanoate (Im) [538] The compounds of Preparations 18 and 10 were reacted according to the same procedure as Preparation 4 and Example 1 to give the title compound.

[539] I

[540] ^' H-NMR(400MHz, CDCl ) δ 8.0(m, IH), 7.8(m, IH), 7.8(m, IH), 7.7(m, IH), 7.5(m, 2H), 7.4-7.3(m, 2H), 6.7(m, IH), 5.0-4.9(m, 2H), 4.9-4.8(m, IH), 4.2-4.0(m, 2H), 3.1(dd, J = 24.8Hz, IH), 2.9-2.6(m, 3H), 1.9(m, IH), 1.7(m, IH), 1.4(two s, 9H), 0.8(m, 3H) [541]

[542] Example 27

[543] (35)-3-({[5-ethyl-3-(l-naphthylmethyl)-4,5-dihydro-5-isoxazolyI]carbonyl} amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid ( Inn ) [544] The compound of Example 26 was reacted according to the same procedure as Example 2 to give the title compound. [545] [546] ' H-NMR(400MHz, DMSO-d_g) δ 12.3(br, IH), 8.4(br, IH), 8.0(m, IH), 7.9(m, IH), 7.8(m, IH), 7.5-7.4(m, 5H), 5.0(br, 2H), 4.7(m, IH), 4.0(s, 2H), 3.3(m, IH), 3.1(m, IH), 2.8(m, 2H), 2.5(m, IH), 1.8(m, IH), 1.7(m, IH), 0.8(m, 3H) [547] MS [M+H] ⁺ 561

[548]

[549] Example 28

[550] (35)-5-(^-butoxy)-3-[({5-ethyl-3-[2-(l-naphthyI)ethyl] - 4,5-dihydro-5-isoxazoIyl}carbonyl)amino]-2,5-dioxopentyl 2,6-dichlorobenzoate (In) [551] 1 -Naphthylpropionaldehyde and the compound of Preparation 6 were reacted according to the same procedure as Preparations 1, 2, 3, and 4, and Example 1 to give the title compound. [552] [553] ' H-NMR(400MHz, CDCl ) δ 8.00(d, IH), 7.85(m, IH), 7.76(m, 2H), 7.57-7.28(m, 7H), 7.34-7.27(m, 3H), 5.20-5.05(m, 2H), 4.94 & 4.88(two m, IH), 3.39-3.27(m, 3H), 2.97-2.72(m,.5H), 2.07(m, IH), 1.86(m, IH), 1.46 & 1.45(two s, 9H), 1.00 & 0.96(two t, 3H) [554]

[555] Example 29

[556] (35)-5-[(2,6-dichlorobenzoyl)oxy]-3-[({5-ethyl-3-[2-(l-naphthyl)ethyl] - 4,5-dihydro-5-isoxazolyl}carbonyI)amino]-4-oxopentanoic acid (loo) [557] The compound of Example 28 was reacted according to the same procedure as Example 2 to give the title compound. [558] [559] ' H-NMR(400MHz, DMSO-d_g) δ 8.45(bd, IH), 8.06(d, IH), 7.90(d, IH), 7.77(d, IH), 7.60-7.37(m, 7H), 5.21-5.03(m, 2H), 4.73(m, IH), 3.06(m, 2H), 2.65(bd, 4H), 1.91 & 1.74(two m, 2H), 0.84(m, 3H) [560]

[561] Preparation 19

[562] Ethyl 5-ethyl-3-[(l-naphthyloxy)methyl]-4,5-dihydro-5-isoxazole carboxylate (VII) [563] 2-Ntroethand pyranyl derivative (see Synthesis, 1993, 12, 1206-1203) and ethyl 2-ethylacrylate were reacted and the resdting product was deprotected to give ethyl 5-ethyl-(3-hydroxymethyl)-4,5-dihydro-5-isoxazdecarboxylate (23%). This compound was subjected to bromination (CBr , PPh , 94%) and then reacted with 1-naphthd (NaH, DMF, 82%) to give the title compound. [564] [565] ' H-NMR(500MHz, CDCl ₃) δ 8.20(m, IH), 7.8 l(d, IH), 7.55-7.42(m, 3H), 7.36(m, IH), 6.88(d, IH), 5.01(dd, 2H), 4.22(m, 2H), 3.61(d, IH), 3.07(d, IH), 1.97(m, 2H), 1.27(t, 3H), 0.93(t, 3H) [566]

[567] Example 30

[568] (35)-3-[({5-Ethyl-3-[(l-naphthyloxy)methyl] - 4,5-dihydro-5-isoxazolyI}carbonyl)amino]-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pe ntanoic acid (Ipp) [569] The compounds of Preparations 19 and 10 were reacted according to the same procedure as Preparation 4 and Examples 1 and 2 to give the title compound. [570] [571] ¹ H-NMR(400MHz, DMSO-d 6 ) δ 8.51 (br, IH), 8.13(m, IH), 7.87(m, IH), 7.54-7.38(m, 5H), 7.02(m, IH), 5.18-4.97(m, 4H), 4.71(m, IH), 3.58(two d, IH), 3.21(two d, IH), 2.68(m, 2H), 1.97(m, IH), 1.81(m, IH), 0.86(two t, 3H)

[572] Mass : M+H 577

[573]

[574] Example 31

[575] (35}-3-{[(3-{[(4-Chloro-l-naphthyl)oxy] methyl}-5-ethyl-4,5-dihydro-5-isoxazolyl)carbonyI]amino}-4-oxo-5-(2,3,5,6-tetrafl uorophenoxy)pentanoic acid (Iqq)

[576] The bromo derivative obtained as an intermediate during the process of Preparation 19 and 4-chtoro-l-naphthd were reacted according to the same procedure as Preparation 19 to give ethyl 5-ethyl-3-[(4-chtoro-l-naphthytoxy)methyl] - 4,5-dihydro-5-isoxazdecarboxylate, which was then reacted according to the same procedure as Preparation 4 and Examples 1 and 2 to give the title compound.

[577]

[578] ' H-NMR(400MHz, DMSO-d ) δ 8.65(m, IH), 8.24-8.09(m, 2H), 7.78-7.35(m, 4H), 7.06(m, IH), 5.17-5.07(m, 4H), 4.82-4.69(m, IH), 3.45(two d, IH), 3.23(two d, IH), 2.83-2.52(m, 2H), 1.96-1.79(m, 2H), 0.86(two t, 3H)

[579] Mass : M+H 611

[580]

[581] Preparation 20

[582] tert -Butyl (35)-3-amino-4-hydroxybutanoate

[583] To N-benzytoxycarbonyl-β-t-butylaspartic acid (3.0 g, 9.28 mmd) and NMM (1.12 mi , 1.1 Eq) was added dry tetrahydrofuran (20 mi ) under nitrogen atmosphere. The reaction solution was kept at CPC. Isobutyl chtoroformate (1.26 mi , 1.05 Eq) was added, and the mixture was stirred for about 40 minutes. Thus obtained slurry was filtered under nitrogen, and the resdting solution was added to NaBH (702 mg, 2.0 4 Eq) solution [methand (10 mi )-dry tetrahydrofuran (20 mi )] at -78'C. The resdting mixture was stowly warmed to room temperature (two hours). The reaction was stopped by acetic acid (2.3 mi ), and the reaction solution was distled under reduced pressure to remove methand. The residue was extracted with ethyl acetate (50 mi x 2), washed with water and aqueous sodium chtoride solution, dried (anhydrous Na SO ), 2 4 concentrated under reduced pressure, and separated-purified by column chro- matography (ethyl acetate-hexane, 1 :5) to give an alcohd compound (2.52g, Yield 88%). [584] [585] The benzytoxycarbonyl group of the compound obtained above was removed (Pd/Q under hydrogen balloon for one hour to give the title compound (Yield 100%). [586] [587] ' H-NMR(400MHz, DMSO-d 6 ) δ 4.60(bs, IH), 3.21 (m, 2H), 2.96(m, IH), 2.41(dd, lH), 2.03(dd, IH), 1.40(s, 9H)

[588]

[589] Preparation 21

[590] tert -Butyl (35)-4-hydroxy-3-({[(5i? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazoIyl]carbonyl}amino)butano ate (XVI)

[591] The compound of Preparation 14 was reacted according to the same procedure as Preparation 4 to give an active carboxyϋc acid derivative (Vllf). A mixture of said active carboxy lie acid derivative (Vllf, 224 mg, 0.79 mmd), the amino alcohd derivative prepared in Preparation 20 (166 mg, 1.2 Eq) and HATU (390 mg, 1.3 Eq) was coded to CPC, triethylamine (0.33 mi , 3.0 Eq) was added in a sdvent of DMF(5 mi ), and the resulting mixture was reacted for two hours. The sdvent was distilled under reduced pressure, and the residue was extracted with ethyl acetate (50 mi x 2), washed with water, aqueous sodium bicarbonate solution, and aqueous sodium chtoride solution, dried (anhydrous Na SO ), concentrated under reduced pressure, and 2 4 purified by column chromatography (60-70% EA/Hex) to give the title compound (330 mg, Yield 95%).

[592]

[593] ' H-NMR(400MHz, CEC1 ) δ 9.16(d, IH), 8.55(d, IH), 7.85(d, IH), 7.73-7.70(m, 3 3H), 7.56(NH, d, IH), 4.26(m, IH), 4.12(d, IH), 4.04(d, IH), 3.79(d, IH), 3.75(t, 2H), 2.94(bs, IH), 2.57(m, 2H), 2.41(m, IH), 1.10 & 1.07(two d, 6H) [594]

[595] Example 32

[596] 6-( rt-Butyl) l-ethyl(2_?,45)-4-({[(5i? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazoIyl]carbonyl}amino)-2-hexe nedioate (Iq) [597] To the compound of Preparation 21 (107 mg, 0.24 mmd) and Dess-Martin reagent (153mg, 1.5 Eq) was added dry dichtoromethane (4 mi ), and the mixture was stirred for one hour at room temperature and concentrated under reduced pressure. To the residue were added dry THF (3 mi ) and (carboethoxymethylene)triphenylphosphorane) (108 mg, 1.3 Eq), and the mixture was refluxed for two hours. The reaction mixture was extracted with ethyl acetate (20 mi x 2), washed with water, saturated aqueous sodium bicarbonate solution and aqueous sodium chtoride solution, dried (anhydrous Na SO ), concentrated under reduced 2 4 pressure, and preliminarily purified by prep-chromatography (40% ethyl acetate- hexane) to give the title compound (98 mg, 80%) with the diastereomer ratio of 3:1.

[598]

[599] ' H-NMR(500MHz, CDCl _) of major isomer δ 9.15(d, IH), 8.54(d, IH), 7.86(d, IH), 7.74- 7.62(m, 4H), 6.93(dd, IH), 6.00(dd, IH), 4.98(m, IH), 4.19(qt, 2H), 4.02(d, IH), 3.81(d, IH), 2.58(m, 2H), 2.43(m, IH), 1.36(s, 9H), 1.27(t, 3H), 1.07 & 1.06(two d, 6H)

[600]

[601] Example 33

[602] (35,4E)-6-ethoxy-3-({[(5i? )-5-isopropyI-3-(l-isoquinolinyI)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-6-oxo- 4-hexenoic acid (Irr)

[603] The compound of Example 32 was reacted according to the same procedure as Example 2 to give the title compound.

[604] t

[605] H-NMR(500MHz, MeOD-d ) of major isomer δ 9.04(d, IH), 8.6 l(d, IH), 8.52(d, IH), 7.95(d, IH), 7.81-7.68(m, 3H), 6.94(dd, IH), 6.00(dd, IH), 5.01(m, IH), 4.17(qt, 2H), 3.90(d, IH), 3.82(d, IH), 2.71(d, 2H), 2.39(septet, IH), 1.26(t, 3H), 1.07 & 1.06(two d, 6H)

[606] MS : M + H 454

[607]

[603] Example 34

[609] tert -Butyl (3S, E)-3-({[(5R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl]carbonyI}amino)-5-(met hyIsulfonyl)-4-pentenoate (Ir)

[610] Anhydrous dichtoromethane (4 mi) was added to the compound of Example 21 (109 mg, 0.25 mmd) and Dess-Martin reagent (157 mg, 1.5 Eq), and the mixture was stirred for one hour at room temperature and concentrated under reduced pressure. The reaction was stopped by isopropyl alcohd (0.5 mi). The sdid was removed by filtration under reduced pressure using CeHte. The filtrate was extracted with ethyl acetate (20 mi x 2), washed with water, saturated aqueous sodium bicarbonate solution, and aqueous sodium chtoride solution, dried (anhydrous Na SO ), and concentrated 2 4 ' under reduced pressure to give an aldehyde compound (540mε, Yield 99%).

[611]

[612] πethyl methylsdfonomethanephosphonate (113 mg, 2.0 Eq, Synthesis, 1969, 170) was dissdved in THF (3 mi ), NaH (60% in mineral oil, 20 mg, 2.0 Eq) and above obtained ddehyde compound were added, and the mixture was refluxed for two hours. After extraction by ethyl acetate (20 mi x 2), the extract was washed with water, saturated aqueous sodium bicarbonate solution, and aqueous sodium chtoride solution, dried (anhydrous Na SO ), concentrated under reduced pressure, and purified by prep- chromatography (60% ethyl acetate/hexane) to give the title compound (52 mg, 41%) with the diastereomer ratio of 4:1.

[613] t

[614] ^' H-NMR(500MHz, CDCl ) of major diastereomer δ 9.14(d, IH), 8.55(d, IH), 7.86(d, IH), 7.76-7.65(m, 4H), 6.92(dd, IH), 6.57(dd, IH), 5.03(m, IH), 4.02(d, IH), 3.81(d, IH), 2.94(s, 3H), 2.61(m, 2H), 2.41(septet, IH), 1.36(s, 9H), 1.10 & 1.03(two set of d, 6H)

[615]

[616] Example 35

[617] (35,4 )-3-({[(5/?)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-(methylsulfonyl)-4-pentenoic acid (Iss)

[618] The compound of Example 34 was reacted according to the same procedure as Example 2 to give the title compound.

[619] I

[620] ^' H-NMR(500MHz, MeOD-d ) of major isomer δ 9.04(d, IH), 8.52(d, IH), 7.95(d, IH), 7.82-7.69(m, 3H), 6.90(dd, IH), 6.71(dd, IH), 5.06(m, IH), 3.86(m, 2H), 2.98(s, 3H), 2.76(d, 2H), 2.39(m, IH), 1.C6 & 1.06(two set of d, 6H)

[621] MS : M + H 460

[622]

[623] Preparation method of Examples 36-42

[624] The compounds which were obtained by reacting (iso)quindinealdehyde (or 1- or 2-naphthaldehyde) and ethyl 2-ethyl acrylate (or ethyl 2-propyl acrylate) according to the same procedure as Preparations 1, 2 and 3 (or Preparations 1 and 16) were purified, if necessary, by prep-HPLC using chiral OD column to isdate active chiral isomers. The isdated active chird isomers or inactive chiral isomers were hydrdyzed according to the same procedure as Preparation 4, and the resdting compounds were reacted with t-butyl 3-amino-5-fluoro-4-hydroxypentanoate according to the same procedure as Examples 1 and 2 to give the title compounds of following Examples 36-42.

[625]

[626] Example 36

[627] 5-Fluoro-3-({[(55)-3-(l-isoquinolinyl)-5-propyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxopentanoic acid) (Itt)

[628] 1

[629] ' H-NMR(500MHz, DMSO-d^ δ 9.02(t, IH), 8.61(m, 2H), 8.C6(d, IH), 7.96(m, IH), 7.85(t, IH), 7.78(m, IH), 5.05(bs, 2H), 4.73(m, IH), 3.97-3.92(dd, IH), 3.70-3.65(two d, IH), 2.90-2.70(two m, 2H), 2.03(m, IH), 1.91(m, IH), 1.48(m, IH), 1.32(m, lH), 0.93(m, 3H)

[630] Mass : M+H 416

[631]

[632] Example 37

[633] (3-({[(5S)-5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid) (Iuu)

[634] 1

[635] ' H-NMR(500MHz, DMSO-d^ δ 8.84(s, IH), 8.59(bs, IH), 8.02(m, 2H), 7.75(s, IH), 7.60(m, 3H), 5.01(bs, 2H), 4.73(m, IH), 3.87-3.82(dd, IH), 3.70-3.65(two d, IH), 2.82-2.73(two m, 2H), 2.05(m, IH), 1.95(m, IH), 0.96(m, 3H)

[636] Mass : M+H 401

[637]

[638] Example 38

[639] (3-({[(55)-5-ethyl-3-(2-quinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid) (Ivv)

[640] i

[641] ' H-NMR(500MHz, DMSO-d^ δ 8.61(dd, IH), 8.41(m, IH), 8.02(m, 3H), 7.79(t, IH), 7.65(t, IH), 5.22-5.06(m, IH), 4.72(m, IH), 4.49-4.28(m, IH), 3.84(m, IH), 3.54(m, IH), 2.99-2.54(two m, 2H), 2.01(m, IH), 1.91(m, IH), 0.91(m, 3H)

[642] Mass : M+H 402

[643]

[644] Example 39 [645] (3-({[(5i?)-5-ethyI-3-(3-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid) (Iww)

[646]

[647] ' H-NMR(400MHz, CDCl ) δ (9.25 & 9.16(two s, IH), 8.C8~7.64(m, 5H), 4.90-4.84(m, IH), 4.79-4.54(m, 2H), 4.01-3.93(two d, IH), 3.54(d, IH), 3.03-2.87(m, 2H), 2.27-2.19 & 2.10-2.01(two m, 2H), 1.10-1.06(m, 3H) [648] Mass : M+H 402

[649]

[650] Example 40

[651] 3-({[5-ethyl-3-(8-quinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid) (Ixx) [652] 1

[653] ' H-NMR(500MHz, CDCl ) δ 8.98 & 8.93(two m, IH), 8.56-8.21(m, IH), 8.03-7.94(m, 2H), 7.73(bs, IH), 7.60(m, IH), 7.53-7.48(two m, IH), 4.94-4.64(m, 3H), 4.27-4.22(two d, IH), 3.77(d, IH), 3.07 & 2.92(two m, 2H), 2.31-2.22(m, IH), 2.12-2.05(m, IH), 1.10(t, 3H)

[654] Mass : M+H 402

[655]

[656] Example 41

[657] 3-({[5-ethyl-3-(3-quinolinyl)-4,5-dihydro-5-isoxazoIyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid) (Iyy)

[658] I

[659] ' H-NMR(400MHz, CDCl ) δ 9.32 & 9.25(two d, IH), 8.16-8.03(m, 2H), 7.83-7.73(m, 3H), 7.62-7.55(m, IH), 4.95-4.76(m, 3H), 3.86(two d, IH), 3.45-3.39(two d, IH), 3.17-3.01 (two m, IH), 2.90-2.82(m, IH), 2.27-2.20(m, IH), 2.09-2.00(m, IH), 1.10-1.05(m, 3H)

[660] Mass : M+H 402

[661]

[662] Example 42

[663] 5-Fluoro-3-({[(5R)-5-isopropyl-3-(2-quinoIinyl)-4,5-dihydro-5-isoxazoIyl] carbonyl}amino)-4-oxopentanoic acid) (Izz)

[664] I

[665] ' H-NMR(400MHz, CDCl ) δ 8.24(m, IH), 8.14(m, IH), 8.04(d, IH), 7.88(d, IH), 3 7.79(m, IH), 7.65(m, IH), 7.51(bs, IH), 5.13-4.35(m, 3H), 4.05-4.00(two d, IH), 3.73(d, IH), 3.05-2.82(m, 2H), 2.42(m, IH), 1.10(m, 6H) [666] Mass : M+H 416

[667]

[668] Preparation method of Examples 43-48

[669] The compounds obtained by reacting an a romatic aldehyde (Bioorg. Med. Chem. Lett., 1996, 6 , p2173, J. Org. Chem., 1978, 43 , 1372) and ethyl 2-ethyl acrylate (or ethyl 2-isopropyl acrylate) according to the same procedure as Preparations 1, 2 and 3 (or Preparations 1 and 16) were purified, if necessary, by prep-HPLC using chiral OD cdumn to isdate active chird isomers. The isdated active chird isomers or inactive chird isomers were hydrdyzed according to the same procedure as Preparation 4, and the resdting compounds were reacted with t-butyl 3-amino-5-flioro-4-hydroxypentanoate according to the same procedure as Examples 1 and 2 to give the title compounds of following Examples 43-48.

[670]

[671] Example 43

[672] 3-({[5-Ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal)

[673] I

[674] ' H-NMR(500MHz, DMSO-d_g) δ 8.53(bs, IH), 7.40(m, 2H), 7.32(m, IH), 7.25(m, IH), 5.02(bs, 2H), 4.72(m, IH), 3.60-3.54(two d, IH), 3.46-3.43(two d, IH), 3.40(m, IH), 2.78-2.60(two m, 2H), 1.95(m, IH), 1.85(m, IH), 1.14(s, 6H), 0.88(m, 3H)

[675] Mass : M+H 393

[676]

[677] Example 44

[678] 3-[({3-[3-(tert-Butyl)phenyI]-5-ethyl-4,5-dihydro-5-isoxazolyl}carbonyl)amino] -5-fluoro-4-oxopentanoic acid (Iaa2)

[679] 1

[680] ' H-NMR(400MHz, DMSO-d_g) δ 8.56(dd, IH), 7.67(s, IH), 7.48(m, IH), 7.38(d, 2H), 5.24-5.12(q, IH), 4.76-4.69(m, IH), 4.59-4.26(m, lH), 3.68(m, IH), 3.49-3.43(two d, IH), 2.96-2.56(two m, 2H), 1.98(m, IH), 1.85(m, IH), 1.29(s, 9H), 0.89(d, 3H)

[681] Mass : M+H 407

[682]

[683] Example 45

[684] 3-[({3-[4-(tert-Butyl)phenyl]-5-ethyI-4,5-dihydro-5-isoxazolyl}carbonyl)amino] -5-fluoro-4-oxopentanoic acid (Iaa3) [685] 1 [686] H-NMR(500MHz, DMSO-d ) δ 8.52(bs, IH), 7.58(m, 2H), 7.43(dd, 2H), 5.10(bs, 6 2H), 4.71-4.65(m, IH), 3.65-3.59(two d, IH), 3.40-3.35(two d, IH), 2.86-2.60(two m, 2H), 1.94(m, IH), 1.82(m, IH), 1.24(s, 9H), 0.86(m, 3H) [687] Mass : M+H 407

[688]

[689] Example 46

[690] 5-Fluoro-3-({[(5i?)-5-isopropyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazolyl ]carbonyl}amino)-4-oxopentanoic acid (Iaa4) [691] [692] ' H-NMR(500MHz, CDCl ) δ 7.60-7.53(m, IH), 7.41(m, 2H), 7.27-7.23(m, 2H), 5.20-4.91(m, IH), 4.71(m, IH), 4.54-4.42(m, IH), 3.69-3.64(two d, IH), 3.45-3.38(m, 2H), 3.12-2.77(m, 2H), 2.32(m, IH), 1.22(d, 6H), 1.05(d, 6H) [693] Mass : M+H 407

[694]

[695] Example 47

[696] 3-[({(5i?)-3-[3-(tert-butyl)phenyl] - 5-isopropyl-4,5-dihydro-5-isoxazolyI}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa5)

[697] I

[698] H-NMR(500MHz, CDCl ) δ 7.69(s, IH), 7.48(d, IH), 7.41 (d, IH), 7.35(t, IH), 4.74-4.50(m, 3H), 3.69(d, IH), 3.40(d, IH), 3.06-2.77(m, 2H), 2.32(m, IH), 1.33(s, 9H), 1.04(m, 6H)

[699] Mass : M+H 421

[700]

[701] Example 48

[702] 3-{[(3-[l,l'-biphenyl]-3-yI-5-isopropyl-4,5-dihydro-5-isoxazolyl)carbonyl] amino}-5-fluoro-4-oxopentanoic acid (Iaa6)

[703] 3-Biphenylcarboxaldehyde (see Synthesis, 2003, 337) was used as a starting materid to give the title comound. [704]

[705] H-NMR(500MHz, DMSO-d ) δ 8.42(bs, IH), 7.87(d, IH), 7.73-7.69(m, 4H), 6 7.52(m, IH), 7.45(m, 2H), 7.38(m, IH), 5.03(bs, 2H), 4.63(m, IH), 3.73-3.57(m, 2H), 2.67-2.63(two m, 2H), 2.22(m, IH), 0.89(m, 6H) [706] Mass : M+H 441 [707]

[7C8] Preparation method of Examples 49-59

[709] 4-Substituted pyridine 2-carboxaldehydes were obtained by a method known in US 6043248, JOC 1982, 47, p4315, and they were reacted according to the same procedure as Preparations 1, 2 and 3 (or Preparations 1 and 16). The resdting compounds were purified, if necessary, by prep-HPLC using chird OD column to isdate active chird isomers. The isdated active chird isomers or inactive chird isomers were hydrdyzed according to the same procedure as Preparation 4, and the resdting compounds were reacted with t-butyl 3-amino-5-ftioro-4-hydroxypentanoate according to the same procedure as Examples 1 and 2 to give the title compounds of following Examples 49-59.

[710]

[711] Example 49

[712] 3-({ [5-Ethyl-3-(2-pyridinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaa7)

[713]

[714] ' H-NMR(500MHz, DMSO-d ) δ 12.41(bs, IH), 8.61 (s, IH), 8.59-8.53(dd, IH), 7.87(m, IH), 7.44(m, IH), 5.19-5.04(two d, IH), 4.70(m, IH), 4.45-4.27(m, IH), 3.67(m, IH), 3.42(m, IH), 2.95-2.53(two m, 2H), 1.96(m, IH), 1.86(m, IH), 0.85(m, 3H)

[715] Mass : M+H 352

[716]

[717] Example 50

[718] 3-[({3-[4-(tert-ButyI)-2-pyridinyI] - 5-ethyl-4,5-dihydro-5-isoxazolyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa8)

[719]

[720] ' H-NMR(400MHz, CDCl ) δ 8.58(d, IH), 7.90(s, IH), 7.65(bs, IH), 7.45-7.39(m, IH), 4.98-4.68(m, 3H), 3.92 & 3.88(two d, IH), 3.52 & 3.47(two d, IH), 3.05-2.86(m, 2H), 2.23-2.18(m, IH), 2.C6-2.00(m, IH), 1.38(s, 9H), 1.05(t, 3H)

[721] Mass : M+H 408

[722]

[723] Example 51

[724] 3-[({(5/?)-3-[4-(ter*-butyI)-2-pyridinyI] - 5-isopropyl-4,5-dihydro-5-isoxazolyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa9)

[725]

[726] ' H-NMR(400MHz, CDCl ) δ 8.58(d, IH), 7.88(d, IH), 7.61(bs, IH), 7.43(m, IH), 4.84(m, IH), 4.60(bs, 2H), 3.89-3.82(two d, IH), 3.60-3.55(two d, IH), 3.04-2.86(m, 2H), 2.38(m, IH), 1.38(s, 9H), 1.07(m, 6H) [727] Mass : M+H 422

[728]

[729] Example 52

[730] 3-({[5-Ethyl-3-(4-isobutyl-2-pyridinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (IaalO) [731] [732] ' H-NMR(500MHz, DMSO-d ) δ 8.58-8.52(dd, IH), 8.49(s, IH), 7.68(s, IH), 7.27(s, IH), 5.19-5.04(m, IH), 4.69(m, IH), 4.46-4.29(m, IH), 3.68(m, IH), 3.41-3.37(dd, IH), 2.93-2.46(m, 4H), 1.95-1.85(two m, 3H), 0.86-0.82(m, 9H) [733] Mass : M+H 403

[734]

[735] Example 53

[736] 3-({[3-(4-AcetyI-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazoIyl] carbonyI}amino)-5-fluoro-4-oxopentanoic acid (laall) [737] [738] ' H-NMR(500MHz, CDCl ) δ 8.79(d, IH), 8.35(s, IH), 7.76(d, IH), 7.46(bs, IH), 4.84-4.40(m, 3H), 3.90-3.85(two d, IH), 3.51-3.46(two d, IH), 3.04-2.84(m, 2H), 2_;65(s, 3H), HHHkdkdk2.16(m, IH), 2.02(m, IH), 1.03(m, 3H) [739] Mass : M+H 394

[740]

[741] Example 54

[742] 3-({[3-(4-CyclopropyI-2-pyridinyI)-5-ethyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal2) [743] [744] ' H-NMR(500MHz, DMSO-d ) δ 12.39(bs, IH), 8.41(t, IH), 7.56(d, IH), 7.12(m, 6 IH), 5.19-5.04(m, IH), 4.72-4.66(m, IH), 4.46-4.27(m, IH), 3.69-3.63(m, IH), 3.39-3.35(two d, IH), 2.80-2.74(m, IH), 2.63-2.52(m, IH), 2.00-1.80(m, 3H), 1.06(m, 2H), 0.86-0.80(m, 5H)

[745] Mass : M+H 392 • •

[746] [747] Example 55 [748] 3-({[3-(4-Cyclopentyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal3) [749] 1 [750] ^' H-NMR(500MHz, CDCl ) δ 8.50(d, IH), 7.67(m, 2H), 7.26(m, IH), 4.88-4.82(m, IH), 4.65(bs, 2H), 3.88-3.81(two d, IH), 3.45-3.41(two d, IH), 3.05(m, IH), 2.96-2.80(m, 2H), 2.20-2.12(m, 3H), 2.02-1.96(m, IH), 1.83(m, 2H), 1.72(m, 2H), 1.60(m, 2H), 1.01(t, 3H)

[751] Mass : M+H 420

[752]

[753] Example 56

[754] 3-({[(5/?)-3-(4-cyclopentyl-2-pyridinyl)-5-isopropyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal4)

[755]

[756] ' H-NMR(400MHz, CDCl ) δ 8.58(m, IH), 7.74(d, IH), 7.63(bs, IH), 7.38-7.32(dd, IH), 4.88-4.8 l(m, IH), 4.53(bs, 2H), 3.87-3.79(two d, IH), 3.56-3.53(two d, IH), 3.12-3.04(m, IH), 3.02-2.85(m, 2H), 2.38(m, IH), 2.16(m, 2H), 1.88(m, 2H), 1.78(m, 2H), 1.65(m, 2H), 1.07(m, 6H)

[757] Mass : M+H 434

[758]

[759] Example 57

[760] 3-({[3-(4-Cydohexyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal5)

[761] I

[762] ' H-NMR(400MHz, CDCl ) δ 8.6 l(m, IH), 7.75 (d, IH), 7.64(bs, IH), 7.39-7.33(dd, IH), 4.86-4.53(two m, 3H), 3.87(t, IH), 3.50-3.45(dd, IH), 3.05-2.85(two m, 2H), 2.63(m, IH), 2.22(m, IH), 2.03(m, IH), 1.93-1.80(two m, 5H), 1.44(m, 5H), 1.05(t, 3H)

[763] Mass : M+H 434

[764]

[765] Example 58

[766] 3-({[5-Ethyl-3-(5,6,7,8-tetrahydro-l-isoquinoIinyI)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaal6)

[767]

[768] ' H-NMR(500MHz, DMSO-d ) δ 8.60-8.53(dd, IH), 8.30(d, IH), 7.15(d, IH), 6 5.20-5.05(m, IH), 4.74-4.66(m, IH), 4.45-4.25(m, IH), 3.75-3.68(m, IH), 3.47-3.41 (m, IH), 2.94-2.88(m, 2H), 2.80-2.72(m, 3H), 2.62-2.53(m, IH), 1.99-1.93(m, IH), 1.88-1.80(m, IH), 1.71-1.69(m, 4H), O.88-0.84(m, 3H)

[769] Mass : M+H 406

[770]

[771] Example 59

[772] 5-Fluoro-3-({[5-isopropyl-3-(4-phenyl-2-pyridinyl)-4,5-dihydro-5-isoxazolyl] carbonyI}amino)-4-oxopentanoic acid (Iaal7)

[773]

[774] ' H-NMR(400MHz, CDCl ) δ 8.68(d, IH), 8.14(s, IH), 7.68(m, IH), 7.58(m, IH), 7.54-7.43(m, 5H), 4.86-4.60(m, 3H), 3.92-3.87(two d, IH), 3.62(d, IH), 3.09-2.86(m, 2H), 2.39(m, IH), l.l l-1.06(m, 6H)

[775] Mass : M+H 442

[776]

[777] Preparation method of Examples 60-63

[778] (25)-4-(tert-butoxy)-2-({[(5/?)-5-isopropyμ3-(l-isoquindinyl)-4,5-dihydro-5-isoxa zdyl]carbonyl}amino)-4-oxobutanoic acid [obtained by coupling reaction of Comound (Vllf) with Asp(0-t-Bu)-OMe and hydrdysis] was reacted according to the same procedure as Preparation 5 to give bromomethyl ketone derivative ( tert-butyl (3S )-5-bromo-3-({[(5 -5-isopropyl-3-(l-isoquincfinyl)-4,5-dihydro-5-isoxazdyl]carbony l}amino)-4-oxopentanoate). This bromomethyl ketone derivative was reacted with diphenylphosphinic acid in F/DMF (see Preparation 5) to give diphenylphosphory- toxymethyl ketone derivative, which was then reacted according to the same procedure as Example 2 to give the title compound (Compound of Example 60).

[779]

[780] The compounds of following Examples 61-63 were obtained from l-phenyl-3-(trif]uoromethyl)-l H-pyrazd-5-d, 3-benzyl-4-hydroxy-2(5 H)-furanone, or isobutyric acid according to the same procedure as above.

[781]

[782] Example 60

[783] (3S)-5-[(diphenylphosphoryl)oxy]-3-({[(5R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyI]carbonyI}amino)-4-oxo pentanoic acid (Iaal8)

[784]

[785] ' Η-NMR(500MΗz, DMSO-d ) δ 8.92(m, IH), 8.58(m, IH), 8.05(m, IH), 7.94(m, 6 IH), 7.8 l(m, IH), 7.75-7.72(m, 3H), 7.57(m, 3H), 7.49(m, 4H), 7.35(m, 2H), 4.90-4.65(two m, 3H), 3.79-3.75(two d, IH), 3.69-3.67(two d, IH), 2.65(two m, 2H), 2.22(m, IH), 0.84(m, 6H) [786] Mass : M+H 614

[787]

[788] Example 61

[789] (35)-3-({[(5i?)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-{[l-phenyl-3-(trifluoromethyl)-l JY-pyrazoI-5-yl] oxy}pentanoic acid (Iaal9)

[790] 1

[791] H-NMR(500MHz, DMSO-d_g) δ 8.95(m, IH), 8.83(d, IH), 8.57(m, IH), 8.03(d, IH), 7.92(d, IH), 7.80(m, IH), 7.74(m, IH), 7.65(d, IH), 7.57(m, IH), 7.51-7.34(m, 3H), 6.27(s, IH), 5.29-5.15(m, 2H), 4.76(m, IH), 3.92-3.88(m, IH), 3.75-3.69(m, IH), 2.84-2.60(m, 2H), 2.33(m, IH), 0.96(m, 6H) [792] Mass : M+H 624

[793]

[794] Example 62

[795] (3ό)-5-[(4-benzyI-5-oxo-2,5-dihydro-3-furanyl)oxy]-3-({[(5 R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-4-oxo pentanoic acid (Iaa20) [796] [797] ' H-NMR(500MHz, DMSO-d ) δ 8.97(t, IH), 8.58(d, IH), 8.04(d, IH), 7.92(d, IH), 7.81(m, IH), 7.73(m, IH), 7.23-7.07(m, 6H), 7.51(m, IH), 4.79-4.65(m, 3H), 3.92-3.87(two d, IH), 3.74-3.68(two d, IH), 2.82-2.58(m, 2H), 2.31(m, IH), 0.95(m, 6H) [798] Mass : M+H 586

[799]

[800] Example 63

[801 ] (35)-5-(isobutyryloxy)-3-({[(5/? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-4-oxo pentanoic acid (Iaa21)

[802]

[803] H-NMR(500MHz, DMSO-d 6 ) δ 12.39(bs, IH), 8.96(t, IH), 8.73(m, IH), 8.58(dd, IH), 8.04(d, IH), 7.92(d, IH), 7.81(t, IH), 7.73(m, IH), 4.78(m, 2H), 4.68(m, IH); 3.87(t, IH), 3.73-3.68(two d, IH), 2.79-2.60(two m, 2H), 2.56(m, IH), 2.3 l(m, IH), 1.05(d, 3H), 0.95(m, 9H) [804] Mass : M+H 484

[805] [806] Example 64

[807] (35)-3-({[(5i?)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-hexenoic acid (Iaa22)

[803] Weinreb amide derivative of (25)-4-(tert-butoxy)-2-({ [(5R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxobut anoic acid (condensed derivative with N,0-dimethylhydroxylamine) and vinyl magnesium bromide were reacted, and the resdting compound was reacted according to the same procedure as Example 2 to give the title compound.

[809]

[810] ' H-NMR(400MHz, DMSO-d 6 ) δ 12.27(bs, IH), 8.95(t, IH), 8.74-8.67(two d, IH), 8.58(m, IH), 8.04(d, IH), 7.92(d, IH), 7.83-7.72(m, 2H), 6.47(m, IH), 6.22-6.11 (two dd, lH), 5.71-5.62(two dd, lH), 4.77(m, IH), 3.90-3.79(m, IH), 3.72-3.64(m, IH), 2.82(m, IH), 2.62-2.49(m, IH), 2.30(m, IH), 0.94(m, 6H)

[81 1] Mass : M+H 410

[812]

[813] Preparation 22

[814] t -Butyl (3S)-3-amino-4-hydroxy-5-(2-pyridinyIoxy)pentanoate (VDIf)

[815] The bromomethyl ketone derivative X (3.2 g, 7.93 mmd), an intermediate in Preparation 5, was dissdved in benzene (30 mi ), Ag CO (2.62 g, 1.2 Eq) and 2-hydroxypyridine (0.93 g, 1.2 Eq) were added, and the mixture was stirred under refkix at 8CPC for 3 days. The reaction mixture was filtered through Celite, concentrated under reduced pressure, and purified by column chromatography to give 2-pyridinytoxymethyl ketone derivative (Xlf) (466 mg, Yield 14%).

[816]

[817] 2-Pyridinytoxymethyl ketone derivative (Xlf) (227 mg, 0.548 mmd) thus obtained was dissdved in a sdvent mixture of tetrahydrofuran/methand (3:2 v/v) (10 mi ), NaBH (43 mg, 2.0 Eq) was added at 0°C, and the mixture was stirred for 30 minutes 4 at room temperature. The reaction was stopped by saturated ammonium chtoride solution, and the reaction solution was concentrated under reduced pressure. The residue was extracted with ethyl acetate, washed with water and aqueous sodium chtoride solution, dried (anhydrous Na SO ), and concentrated under reduced pressure to give Compound (XB ) (230 mg) where the ketone group was reduced to hydroxyl group. [818] [819] The benzytoxycarbonyl group of the compound prepared above was removed (Pd/Q under hydrogen baEoon for 40 minutes to give the title compound (155 mg, 99%). [820]

[821] Preparation method of Examples 65-66

[822] Compound Vllf (or VIIu) andVIIIf were reacted according to the same procedure as Examples 1 and 2 to give the title compounds of Examples 65-66. Here, VIIu represents5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdecarboxylic acid. [823]

[824] Example 65

[825] (35)-3-({[(5i?)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl] carbonyl}amino)-4-oxo-5-(2-pyridinyIoxy)pentanoic acid (Ϊaa23) [826] [827] ' H-NMR(500MHz, MeOH-d^) δ 9.04(d, IH), 8.50(d, IH), 7.95(d, IH), 7.8 l(d, IH), 7.77(t, IH), 7.69(t, IH), 7.59(m, IH), 6.85-6.80(m, 2H), 6.67(bs, IH), 5.07(bs, IH), 4.95(t, IH), 4.84(m, IH), 3.94-3.79(Abq, 2H), 2.92-2.80(m, 2H), 2.39(m, IH), 1.09(m, 6H) [828] Mass : M+H 491

[829]

[830] Example 66

[831 ] (35)-3-([[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazolyI] carbonyl}amino)-4-oxo-5-(2-pyridinyloxy)pentanoic acid (Iaa24) [832] [833] ' H-NMR(500MHz, DMSO-d ) δ 8.71(bs, IH), 8.02-7.94(two bs, IH), 6 7.71-7.64(m, IH), 7.42-7.18(m, 4H), 6.96-6.90(two t, IH), 6.85-6.80(two d, IH), 4.99(bs, 2H), 4.86-4.78(m, IH), 3.58(two d, IH), 3.48(two d, IH), 3.36(m, IH), 2.81-2.61(m, 2H), 2.05-1.80(two m, 2H), 1.14-1.03(m, 6H), 0.93-0.88(m, 3H)

[834] Mass : M+H 468.21

[835]

[836] Example 67

[837] 2-{[(3S)-4-carboxy-3-({[(5i? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyI]carbonyl}amino)-2-oxo butyI]oxy}-l-methyIpyridinium trifluoromethanesulfonate (Iaa25) [838] The intermediate t- butyl ((3S)-3-({ [(5R )-5-isopropyl-3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxo-5-( 2-pyridinytoxy)pentanoate (49 mg, 90 μmd) obtained after the Dess-Martin oxidation reaction in Example 65 was dissdved in dichtoromethane (2 mi ), methyl trifluo- romefhanesdfonate (1.1 Eq, 10.1 βi ) was added, and the mixture was stirred for one day at room temperature. After concentration under reduced pressure, the residue was subjected to the same procedure as Example 2 to give the title compound (60 mg).

[839]

[840] ' H-NMR(500MHz, DMSO-d ) δ 9.00-8.9 l(m, 2H), 8.76-8.57(m, 2H), 8.42(m, IH), 8.04(m, IH), 7.93(m, IH), 7.80(m, IH), 7.75(m, IH), 7.54(m, IH), 5.77-5.48(m, 2H), 4.85-4.81(m, IH), 4.00(s, 3H), 3.94-3.69(m, 2H), 2.87-2.60(m, 2H), 2.33(m, IH), 0.98 & 0.94(two d, 6H)

[841] Mass : M+ 505.20

[842]

[843] Example 68

[844] 2-{[(3S)-4-carboxy-3-({[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazolyl ]carbonyl}amino)-2-oxobutyl]oxy}-l-methylpyridinium trifluoromethane- sulfonate (Iaa26)

[845] The intermediate t -butyl (35 )-3-( { [5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxo -5-(2-pyridinytoxy)pentanoate(55 mg, 0.105 mmd) obtained after the Dess-Martin oxidation reaction in Example 66 was dissdved in dichtoromethane (2 mi ), methyl tri- fluoromethanesdfonate (1.1 Eq, 13 βi ) was added, and the mixture was stirred for one day at room temperature. After concentration under reduced pressure, the residue was subjected to the same procedure as Example 2 to give the title compound (59 mg, 94%).

[846]

[847] H-NMR(500MHz, DMSO-d 6 ) δ 8.80-8.73(two d,lH), 8.65(m, IH), 8.45-8.38(m, IH), 7.56- 7.5 l(m, 2H), 7.43-7.3 l(m, 3H), 7.24-7.12(m, H), 5.72-5.48(m, 2H), 4.91(m, IH), 4.01 & 3.99(two s, 3H), 3.64(two d, IH), 3.48(two d, IH), 3.42(m, IH), 2.90-2.62(m, 2H), 2.05-1.80(two m, 2H), 1.15-1.03(m, 6H), 0.93-0.88(m,3H).

[848] Mass : M+ 482.17

[849]

[850] Preparation method of Examples 69-70 :

[851 ] Oxime derivative of 5-chtoro- 1 -methyl- 1 H-indd-2-ddehyde or 1 ,5-dimethyl- 1 H - indd-2-ddehyde was reacted with t-butyl 3-amino-5-fluoro-4-hydroxypentanoate according to the same procedure as Preparations 1, 17, 4 and Examples 1, 2 to give the title compounds of Examples 69-70.

[852]

[853] Example 69

[854] 3-({[3-(5-chloro-l-methyl-lH-indol-2-yl)-5-isopropyl-4,5-dihydro-5-isoxazolyl] carbonyI}amino)-5-fluoro-4-oxopentanoic acid (Iaa27)

[855] 1

[856] ' H-NMR(500MHz, CDCl ) δ 7.59(s, IH), 7.46-7.39(two d, IH), 7.30-7.23(m, 3H), 5.01(m, IH), 4.75-4.46(m, 2H), 4.02(d, IH), 3.95(s, 3H), 3.71(d, IH), 2.95(m, IH), 2.77(m, IH), 2.35(m, IH), 1.04(m, 6H)

[857] Mass : M+H 452

[858]

[859] Example 70

[860] 3-({[3-(l,5-dimethyl-lH^r-indol-2-yl)-5-isopropyl-4,5-dihydro-5-isoxazoIyl] carbonyI}amino)-5-fluoro-4-oxopentanoic acid) (Iaa28)

[861] 1

[862] ' H-NMR(500MHz, CDCl ) δ 7.48(bs, IH), 7.39(d, IH), 7.23-7.14(m, 3H), 4.76(m, IH), 4.70-4.50(m, 2H), 4.07-4.02(two d, IH), 3.99, 3.94 & 3.93(three s, 3H), 3.75-3.48(m, IH), 2.94-2.82(two m, IH), 2.46-2.43(two s, 3H), 2.34(m, IH), 1.05(m, 6H)

[863] Mass : M+H 432

[864]

[865] Preparation 23

[866] Resolution of (5/?)-5-isopropyl-3-(l-isoquinolinyI)-4,5-dihydro-5-isoxazole carboxylic acid

[867] 5-Isopropy^3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdecarboxylic acid was dissdved in acetone (190 mi ) by heating at 60 °C, and (S)- a -methyl-benzylamine (14.5 mi , 112 mmd) was added. The reaction mixture was coded to room temperature and stirred for 4 hours. The resdting precipitate was filtered and washed three times by acetone (40 mi ).

[868]

[869] Thus obtained (S)- a -methyl-benzylamine salt of (5 R )-5-isopropyt3-(l-isoquincfinyl)-4,5-dihydro-5-isoxazdecarboxylic acid was dissdved in the mixture (150 mi ) of acetone and water (4:1) by heating at 90 °C, coded to room temperature, and stirred for 3 hours. The resdting precipitate was filtered and washed by acetone (40 mi ) three times to give pure ( S)- a - methyl-benzylamine sdt of (5 R )-5-isopropy+3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdecarboxy^]ic acid (12.8g, 24.3%, 99.8% ee).

[870]

[871] The opticd purity of (5 R )-5-isopropyt3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdecarboxylic acid was estimated by using ChirdCel OD column (4.6 x 250 mm, 5 m m). The mixture of n- hexane/isopropand/trifluoroacetic acid (92/8/0.1) was used as the mobile phase at the flow rate of 1 mi /min, the cdumn temperature was 40 °C, and the detection wavelength was 225 nm. The two optical isomers were observed at the retention times of 7.8 min (R isomer) and 21.1 min (S isomer), respectively.

[872]

[873] Example 71

[874] Resolution of Compound (Iii-1)

[875] 1) Isolation of the SEED compound

[876] The two diastereomers of Example 16 were separated by using preparative liquid chromatography silica column (diameter 40 mm, DYNAMAX-100A). The mixture of n-hexane/ethand/trifluoroacetic acid (4000/32/2) was used as the mobile phase at the flow rate of 50 mi /min, and the desired diastereomer was collected with the ratio of 99: 1 during the retention time of 62-66 min at the detection wavelength of 227 nm (the two diastereomers were broady eluted with the continuously changed ratio until 86 min). Thus obtained diastereomer of the 99: 1 ratio was deprotected and used as the seed for the resolution.

[877]

[878] The opticd purity was estimated by using Atlantis C column (4.6 x 250 mm, 5 m 18 m). The mixture of acetonitrfle/water/trifiuoroacetic acid was used as the mobile phase at the flow rate of 1 mi /min according to the fctowing gradient:

[879]

[880] t = 0min, 0:100:0.1

[881] 3min, 20:80:0.1

[882] 50min, 100:0:0.1

[883]

[884] Lhder the detection wavelength of 227 nm, the two optical isomers were observed at the retention times of 36.6 min (3R, 5R isomer) and 37.1 min (3S, 5R isomer), respectively. [885] [886] (3S, 5R isomer): terf-butyl (35)-5-fluoro-3-({[(5i? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-4-oxo pentanoate [887] [888] ' H-NMR(500MHz, CDCl ) δ 9.13(d, IH), 8.55(d, IH), 7.85(d, IH), 7.78-7.65(m, 4H), 5.22-5.02(two m, 2H), 4.90(m, IH), 4.02(d, IH), 3.80(d, IH), 2.92-2.88(dd, IH), 2.79-2.75(dd, IH), 2.41(m, IH), 1.34(s, 9H), 1.09(m, 6H) [889] Mass : M+H 472

[890] [891] (3R, 5R isomer): tert-butyl (3/?)-5-fluoro-3-({[(5i? )-5-isopropyl-3-(l-isoquinoIinyI)-4,5-dihydro-5-isoxazoIyl]carbonyl}amino)-4-oxo pentanoate [892] [893] ' H-NMR(400MHz, CDCl ₃) δ 9.14(d, IH), 8.56(d, IH), 7.87(d, IH), 7.77-7.64(m, 4H), 5.25-5.00(two q, 2H), 4.90(m, IH), 4.03(d, IH), 3.82(d, IH), 2.93(dd, IH), 2.77(dd, IH), 2.42(m, IH), 1.35(s, 9H), 1.1 l(m, 6H) [894] Mass : M+H 472

[895] [896] (35>5-fluoro-3-({[(5/? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazoIyl]carbonyl}amino)-4-oxo pentanoic acid (Iii-1) [897] [898] ' H-NMR(400MHz, CDCl ) δ 9.07(d, IH), 8.57(d, IH), 7.89(d, IH), 7.78-7.69(m, 3H), 7.69(d, IH), 4.88-4.79(m, 2H), 4.67(bs, IH), 4.07(d, IH), 3.8 l(d, IH), 3.C8-2.93(m, IH), 2.91-2.82(m, IH), 2.43(m, IH), 1.12(m, 6H) [899] Mass : M+H 416

[900] [901] (3i?)-5-fluoro-3-({[(5i? )-5-isopropyl-3-(l-isoquinoIinyl)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-4-oxo pentanoic acid (Iii-2)

[902] i

[903] ' H-NMR(500MHz, CDCl ) δ 9.07(d, IH), 8.55(d, IH), 7.87(d, IH), 7.75-7.68(m, 3H), 7.52(bs, IH), 5.20-4.35(m, 3H), 4.02(d, IH), 3.80(d, IH), 3.13-2.90(m, 2H), 2.39(m, IH), l.C8(m, 6H) [904] Mass : M+H 416 [905] [906] 2) Recrystallization [907] (3S)-5-fluoro-3-({[(52? )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazolyl]carbonyl}amino)-4-oxo pentanoic acid (Iii-1)

[9C8] Crude t-butyl 5-fluoro-3-([ [(5R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxopen tanoate (366 g) was dissdved in methylene chtoride (1.9 kg) and coded to 0 °C. Tri- ethylsilane (235 g) and trifhioroacetic acid (1.88 kg) were added and stirred for one hour at 0 C. The reaction mixture was distilled under reduced pressure, redissdved in ethyl acetate (2.4 kg), and the pH was adjusted to 5.2 by adding 2N aqueous sodium hydroxide solution (3.1 L). The organic layer was separated and the aqueous layer was extracted once with ethyl acetate (2.4 kg). Combined organic layer was distled under reduced pressure to remove the sdvent, the resdting residue was dissdved in methyl t-butyl ether (530 g), and small amount of crystalline (3 S)-5-fluoro-3-({ [(5 R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-oxopen tanoic acid was added. After stirring for 16 hours at room temperature, resdting precipitate was filtered and washed with the 9: 1 mixture of methyl t-butyl ether and n- hexane (210 m -

[909]

[910] Thus obtained (35>5-fluoro-3-( { [(5 R )-5-isopropyl-3-( 1 -isoquinoϊnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopen tanoic acid was dissdved in ethyl acetate (240 mi ) by heating at 50 °C, n-hexane (240 mi ) was stowly added, and gradually coded to room temperature. After stirring for 24 hours at room temperature, the resdting precipitate was filtered and washed with the 1:1 mixture of ethyl acetate and n-hexane (30 mi ) to give the title compound (Iii-1, 46.0 g, 3S/3R=94/6.0). The opticd purity was estimated using Luna column (4.6 x 250 mm, 5 m m, C ). The mixture of acetonitrile/20mM NH[ OAc (pH 6) (30/70) was used 13 4 as the moble phase at the flow rate of 1 mi /min. Lhder the detection wavelength of 227nm, the two optical isomers were observed at the retention times of 8.0 min (3R isomer) and 9.0 min (3S isomer), respectively. [911] ^• [912] Experiment 1

[913] Determination of the caspase inhibitory effect

[914] Caspase-1 and caspase-8 known as cysteine proteases in the form of α β were 2 2 expressed, purified, and activated by modifying a method known in Thornberry, N. A. et d, Nature, 1992, 356, 768. Thornberry, N. A. Methods in Enzymology, 1994, 244, 615. Walker, N. P. C. et d. Cell, 1994, 78, 343, and caspase-9 was dso purified by a similar method, and the inhibitory activity against them was tested. Briefly describing, plO and p20 subunits (Thornberry, N. A. et d, Nature, 1992, 356, 768) were expressed in Ecoli and purified by nickel column and anionic exchange chromatography to give caspase-1, caspase-8 and caspase-9. The fluorescent substrate AcYVAD-AFC for thus obtained caspase-1, AcDEVD-AFC for caspase-8, and AcLEHD-AFC for caspase-9 were used for determining specific activity of the synthesized inhibitors. The enzyme reaction was carried out at 25 °C with various concentrations of the inhibitors in a buffer solution containing 50mM HEPES(pH 7.50), 10%(w/v) sucrose, 0.1%(w/v) CHAPS, lOOmM NaCl, ImM EDTA, and lOmM DTT in the presence of 50μM AcYVAD-AFC for lOnM caspase-1, 50μM AcDEVD-AFC for 2.1nM caspase-8, and 150μM AcLEHD-AFC for 200nM caspase-9. The inhibitory constants K and K of i obs the inhibitors were determined by measuring the reaction velocity with the time lapse using a fluorescent spectrometer and by obtaining the initial rate constant. K was i calculated from the Lineweaver Burk Plot, and K from the following Equation 1. obs [915] [916] Equation 1

[917] K = 4n (l-A /A )/t obs ; oo

[918] in which

[919] A means cleavate rate (%) at time t, and t

[920] A means the maximum cleavage rate (%). 00

[921 ] Spectra MAX GeminiXS Fluorescent Spectrometer of Mdecdar Device Co. was used at the excitation wavelength of 405nm and the emission wavelength of 505 nm.

[922]

[923] The in vivo inhibitory activity of the inhibitors was determined by subjecting Jurkat eel (ATCC TIB-152) to apoptosis using Fas antibody (Upstate Biotech 05-201) and by detecting the color change according to the WST-1 method known in Francoeur A.M. and Assalian A. (1996) Biochemica 3, 19-25 to observe the amount of alive Jurkat cells when the eels were treated by the inhibitor. Spectra MAX 340 Spectrometer of Mdecdar Device Co. was used at the absorbance wavelength of 440nm. [924] [925] Tatlel

[926] * Compound Iii-u is the (5S) form of Comound Iii.

[927]

[928] Experiment 2

[929] Therapeutic effect for LPS-induced acute hepatitis in mouse

[930] Step 1) Preparation of Hood sample

[931] Female Bato/c mice (6 weeks, Charles River Laboratory, Osaka , Japan ) were kept under the conditions of 22°C, 55% of relative humidity, and Ight-darkness cycle of 12 hours. Food and water were suppled ad libitum. In pyrogen-free saline were dissdved LPS (Hpopdysaccaride) and D-galactosamine in concentrations of 0.4 mg / mi and 280 mg / mi , respectively, and their 1:1 mixture was injected to mice in the amount of 5 mi I kg . Immediately after the injection of LPS and D-galactosamine, vehicle (a mixture of PEG400 : ethand : TweenδO = 15 : 7.5 : 2.5 was diluted by five times with saline) wherein the test compound is dissdved or the vehicle atone was intraperitonealy injected into the mice. After 8 hours from the drug injection, blood samples were obtained from their hearts.

[932]

[933] Step 2: Determination of the activity of plasma aminotransferase

[934] The plasma ALT activity was determined for the Hood samples obtained in Step 1 using ALT assay kit (Asan Pharm. Co., Seod , Korea ) according to the manufacturer's instruction. As a resdt, it appeared that the injection of LPS and D-galactosamine steeply increases the ALT activity in plasma, and the test compounds inhibit the increased enzyme activity in a dose-dependent manner. Based on these resdts, ED 50 values of the test compounds were calcdated using Prism software of GraphPad Co. to give 0.01-lOmg/kg. [935]

[936] Experiment 3

[937] Inhibitory effect against hepatic fibrosis in SD rats

[938] Step 1) Induction of hepatic fibrosis and administration

[939] Mde Spargue-Dawley rats (6 weeks, Korea Biolink) were kept under the conditions of 22°C, 55% of relative humidity, and Kght-darkness cycle of 12 hours. Food and water were supplied ad libitum. For the ligation of biliary duct, the rats were anesthetized by inhalation of 1% hatothane, abdomen of the rats were cut open, the distd and proximd biliary ducts were Kgated, the part between the ligation sites were cut, 2 mi of saline was injected, and sutured.

[940] [941] Test compound (Iii) was orally administered in a dosage of 3 mg / kg or 10 mg / kg twice a day. That is, the compound was dissdved in a cosdvent (PEG400 : ethand : Tween80 = 15 : 7.5 : 2.5), diluted with phosphate buffer (pH 7.4) by five times, and administered. To the contrd group was administered the solution without the test compound. The administration was made for 1 week after 1 week from the ligation of biliary duct.

[942]

[943] Step 2: Preparation of tissue section and Sirius red staining

[944] After the administration, the rats were sacrificed. The livers were fixed by 10% neutrd formalin and a paraffin section of 5 μm thickness was prepared and stained by 0.1% Sirius red (Direct red 80, Sigma). The tissue section was investigated by an o pticd microscope to observe the cclagen fibers stained in red, and the resdts are represented in Figure 1.

[945]

[946] Experiment 4

[947] Inhibitory effect against apoptosis during the bile stagnation in SD rats

[948] The test compound (Iii) was administered to the SD rats whose biliary ducts were Hgated according to the procedure as Step 1 of Experiment 3. After 2 weeks from the operation, the rats were sacrificed. The livers were fixed by 10% neutrd formalin and a paraffin section of 5 μm thickness was prepared. TUNEL staining was carried out using ApopTag Peroxidase In Situ Apoptosis Detection kit (Chemicon) according to the manufacturer's instruction. More than 10 sites of the TUNEL stained liver tissue were photographed in 200 magnifications without any overlap, of which resdt was shown in Figure 2. The number of eels suffering apoptosis in each test group was counted and represented in the following TaUe 2. In the following taUe, the Sham operation means the case where the biliary duct was exposed but not ligated, and the BDL operation means the case where oriy the vehicle was administered after the ligation of biliary duct.

[949]

[950] TaHe2

[951] Inhibitory effect of compound (Iii) against hepatic eel apoptosis during the bile stagnation

[952] (Unit: TUNEL positive eels / field)

[953] [954] Conclusion [955] The effective inhibition of apoptosis (75% inhibition) by Compound (Iii) was shown by TUNEL staining in a model established by the induction of hepatic fibrosis through the bile stagnation. In addition, the Sirius Red staining showed a severe fibrosis in the contrd group, but dmost no fibrosis in the Compound (Iii) treated group. This resdt demonstrates the inhibitory effect of Compound (Iii) against hepatic fibrosis in rats, and so it is expected that Compound (Iii) can exhibit the pharma- cotogicd activity of suppressing Ever cirrhosis by inhibiting the apoptosis of hepatic eel in cKnicd application. The application may be expanded not oriy to the hepatic cirrhosis by bile stagnation, but dso to various hepatic diseases where hepatic fibrosis due to the apoptosis is included.

[956] [957] Experiment 5 [958] Antiphlogistic effect in rats [959] Male SD rats (6 weeks,. Orient) were kept under the conditions of 22°C, 55% of relative humidity, and light-darkness cycle of 12 hours. Food and water were supplied ad libitum. Before the induction of edema, the foot volume of each rat was measured by plethysmometer. Before the induction of edema, vehicle (a mixture of PEG400 : ethand : Tween80 = 15 : 7.5 : 2.5 was diluted by ten times with phosphate buffer) wherein the test compound is dissdved or the vehicle atone was oraly administered into the rats. Carrageenan (gamma) was dissdved in the concentration of 1% in saline, and subcutaneously injected into the right rear foot of the rats in the dosage of 100 μi . After 3 hours, the right foot volume was measured again by plethysmometer. The effect of the test compound was shown by edema inhibition (%) (see Table 3). The edema inhibition (%) was cdcdated according to the following Equation 2.

[960] [961] Equation 2 [962] Edema Inhibition (%) = 100 x (Average of the increased foot volume in the vehicle-administered group - Increased foot volume in the test compound-administered group)/Average of the increased foot volume in the vehicle-administered group [963] [964] Tade3 [965] Edema inhibition effect of Compound (Iii)

Edema inhibition effect (%) Dosage (mg/kg) Average SEM 2.3 7.7 30 20.7 9.7 100 22.7 2.6 [966] [967] Experiment 6 [968] Therapeutic effect for rheumatic arthritis in rats [969] Femde Lewis rats (7 weeks, Charles River , Japan ) were kept under the conditions of 22°C, 55% of relative humidity, and light-darkness cycle of 12 hours. Food and water were suppled ad libitum. Type II cdlagen (bovine) was dissdved in 0.05M acetic acid in a concentration of 2 mg/ mi at 4°C, and the same amount of Complete Freund's adjuvant was added to emdsify the solution at 4°C. 0.1 mi of thus emdsified solution was subcutaneously injected into the rattail of the Lewis rats. After 7 days, the emdsified solution was injected again in the same manner. From the date on which the second emdsified sdution was injected, vehicle (a mixture of PEG400 : ethand : Tween80 = 15 : 7.5 : 2.5 was diluted by ten times with phosphate buffer) wherein the test compound is dissdved or the vehicle atone was oraly administered into the rats every day. On Day 14 from the first injection of the coJagen-containing emdsified solution, the right rear foot volume was measured again by plethysmometer (see TaHe 4). The edema inhibition (%) was determined by the f bwing Equation 3.

[970] [971] Equation 3 [972] Edema Inhibition (%) = 100 x (Average of the increased foot volume in the vehicle-administered group on Day 14 - Increased foot volume in the test compound- administered group on Day 14)/Average of the increased foot volume in the vehicle- administered group on Day 14

[973] [974] Further, p-va ie was cdcdated by Student t-test from the increased foot volume on Day 14 to confirm the significance.

[975] [976] TaHe4 [977] Foot edema inhibition effect

[978] * p-va e = 0.032 [979] [980] In the foot edema test in rats, Compound (Iii) showed a dose-dependent edema inhibition effect of about 2, 21, and 23% at a dosage of 3, 30, and 100 mg/kg, respectively. In the model of rheumatic arthritis, the foot edema was decreased sig- -nificantly (about 70% decrease) in the Compound (Iii)-administered group on Day 14 when the negative contrd group showed the maximum edema. Therefore, it is considered that Compound (Iii) has an inhibitory effect against the progress of inflammation in an inflammatory disease model, and so can treat the autoimmune inflammatory diseases.

[981] [982] Experiment 7 [983] Effect comparison with the known compound [984] Compound (Iii) according to the present invention and LB84068MP (Compound 68) known in PCT/KROO/01047 (WO 01/21600) were tested and the resdts are shown in the following Table 5.

[985] [986] TaHe 5

[987] [988] As can be seen from the above Table 5, Compound (Iii) according to the present invention showed an increased inhibitory activity by 10 times or more against caspase- 8 and Jurkat eel compared with LB84068MP, and by about 100 times against LPS- induced acute hepatitis model (mouse). Also, regarding the physico-chemical properties, the compound showed improved sdublty, and so can be easily used as an injection. That is, the compound of the present invention shows highly more improved effects than the comparison compound of LB84068MP in both aspects of activity and physico-chemical properties.

Claims (1)

1. Claims

   [1] 1. A compound of the following formda (1):

   (1) in which I) R represents H, simple dkyl chain (-SAQ, simple cycbdkyl chain (-SCAQ, aryl group (-Ar), or simple dkyl chain substituted by aryl (-SAC-Ar), [3] II) R represents -SAC, -SCAC, -Ar, -SAC-Ar, or a side chain residue of al the natural amino acids; and the compound of formda (1) may exist in a specific diastereomeric form, or mixtures thereof when the carbon to which R is attached becomes a stereocenter due to the R group; or the compound of formda (1) may have a protecting group in an ester form (-CO R wherein R is -SAQ or a 4 4 ² sdfonamide form (-CONHSO R wherein R is -SAQ, or may exist in the form of pharmaceuticaly acceptaHe salt, when R is a side chain residue of an amino acid containing carboxyl moiety; or the compound of formda (1) may also exist in the form of pharmaceuticaly acceptaHe sdt when R is a side chain residue of an amino acid containing a base moiety, 2 III) R represents -SAC, -SCAC, -Ar, -SAC-Ar, or a side chain residue of the natural amino acids; and the compound of formda (1) may exist in a specific diastereomeric form, or mixtures thereof when the carbon to which R is attached becomes a stereocenter due to the R group; the compound of formda (1) may have a protecting group in an ester form (-00 R wherein R is -SAQ or a ft (\ sdfonamide form (-CONHSO R wherein R is -SAQ, or may exist in the form of pharmaceuticaly acceptaHe sdt, when R is a side chain residue of an amino acid containing carboxyl moiety; or the compound of formda (1) may dso exist in the form of pharmaceuticaly acceptaHe sdt when R is a side chain residue of an amino acid containing a base moiety, or R² further represents H; -(CH ) OR⁷ wherein R⁷ is -SAC, -SCAC, -Ar, or - SAC- 2 n Ar, and n = 1 or 2; or -(CH ) OC(=0)R wherein R⁸ is -SAC, -SCAC, - Ar, or - 2 n SAC-Ar, and n = 1 or 2, TV) A represents -(CH ) - (n = 0-4), -0-(CH ) - (n = 0-4), or -NR⁹-(CH ) - (n = 0- 2 π 2 π 2 n 4) wherein R is -SAC, -SCAC, -Ar, or -SAC-Ar, V) Brepresents H, -SAC, -SCAC, -Ar, or -SAC-Ar, or VI) R and R may form a cycle together with the carbon atom to which they are attached, where -R-R¹- is -(CH ) -, -(CH ) -0-(CH ) -, or -(CH ) -NR¹⁰-(CH ) - _ 2 n 2 n 2 m 2 n 2 m wherein n+m<9 and R is -SAC, -SCAC, -Ar, -SAC-Ar, -C(=0)- SAC, - C(=0)-SCAC, -C(=0)-Ar, or -C(=0)-SAC-Ar, VII) X represents -C(=0)CH OR wherein R is -SAC, -SCAC, -Ar, or - SAC-Ar; -C(=0)CH OC(=0)R¹² wherein R¹² is -SAC, -SCAC, -Ar, or -SAC-Ar; - CH=CH-CO R¹³ wherein R¹³ is -SAC, -SCAC, -Ar, or -SAC-Ar; -CH=CH- SO 2 2 R¹⁴ wherein R is -SAC, -SCAC, -Ar, or -SAC-Ar; -C(=0)CH=CH ; or - COCH 2 -W wherein W is -N , -F, -CI, -Br, -I, -NR^I5R¹⁶ (R¹⁵ and R¹⁶ each are - SAC, - 2 2 SCAC, -Ar, or -SAC-Ar, or together may form 3- to 6-membered saturated or 17 17 uunnssaattuurraatteedd ccyycclliicc ggrroup), -SR (R is -SAC, -SCAC, -Ar, or - SAC-Ar), or is the following formda

   wherein Y is H, -OH, -OR¹⁸ (R^,S = -SAC or -SCAQ, -C(=0)R '⁹ (R¹⁹= -H, -SAC, or - SCAQ, -F, -CI, -Br, -I, -CN, -NC, -N , -CO H, CF , -CO R ° (R²° = -SAC or - 3 2 3 2 SCAQ, -C(=0^«R ²¹ (R²¹ = -SAC or -SCAQ, or -C(=O^R ²²R²³ (R²² and R²³ each are -SAC, -SCAC, -Ar, or -SAC-Ar ), R is H, -SAC, -SAC-Ar, or -Ar, sdt, or stereoisomer thereof.

   [4] 2. The compound according to claim 1 wherein R represents H.

   [5] 3. The compound according to claim 1 wherein R represents -CH COOH, -CH 2 2 COOR³ (R³=SAQ, or -CH CONHSO R⁴ (R⁴ = SAQ. ^{2 2} 2

   [6] 4. The compound according to claim 1 wherein R represents H, -SAC, -Ar, or - (CH ) OR⁷ (R⁷ = -SAC, -SCAC, -Ar, or -SAC-Ar, and n = 1 or 2). 2 n

   [7] 5. The compound according to claim 1 wherein X represents -C(=0)CH OAr, - C(=0)CH OC(=0)Ar, or -COCH -W wherein W is -N , -F, -CI, -Br, -I, -NR ⁶ 15 ²16 ^{2 2} (R and R each are -SAC, -SCAC, -Ar, or -SAC-Ar, or together may form 3- to 17 17 6-membered saturated or unsaturated cyclic group), or -SR (R is -SAC, - SCAC, -Ar, or -SAC-Ar). [8] 6. The compound according to claim 1 wherein I) R represents H, II) R¹ represents -CH COOH, -CH COOR³ (R³=SAQ, or -CH CO HSO R⁴ (R⁴ 2 2 2 7 = SAQ, HI) R² represents H, -SAC, -Ar, or -(CH ) OR⁷ (R⁷ = -SAC, -SCAC, -Ar, or - 2 n SAC-Ar, and n = 1 or 2), IV) A represents -(CH ) - (n = 0-4) or -0-(CH ) - (n = 0-4), 2 π 2 n V) B represents H, -SAC, -SCAC, -Ar, or -SAC-Ar, VI) X represents -COCH N , -COCH F, -COCH CI, -COCH Br, -COCH I, - 2 2 2 2 2 2 COCH OAr, -COCH OCOAr or -COCH SR¹⁷ (R¹⁷ is -SAC, -SCAC, -Ar or - 2 2 2 SAC-Ar). [9] 7. The compound according to claim 1 which is selected from the following group: (1) (35)-5-[(2,6-dichtorobenzoyl)oxy] - 3-( { [5-methyl-3-phenyl-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-oxopentan oic acid (Iaa); (2) (35)-3-({ [5-methyl-3-phenyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-phenoxypentanoic acid (Ibb); (3) (3S)-3-({ [5-ethyl-3-phenyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Ice); (4) (3S)-3-({[5-ethyl-3-(l-naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Idd); (5) (3_S)-3-( { [5-ethyl-3-(2-naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl } amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (lee); (6) (35)-3-( { [5-ethyl-3-( 1 -isoquinoϊnyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid (Iff); (7) 3-( { [5-ethyl-3-( 1 -isoquinoϋnyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-flιoro-4-oxopentanoic acid (Igg); (8) ethyl 3-({ [5-ethyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl } amino)-5-fkιoro-4-oxopentanoate (Ihh) ; (9) 5-fluoro-3-({[(5R)-5-isopropy+3-(l-isoquinoHnyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxopentanoic acid (Iii); (10) 3-({ [5-ethy+3-(4-quincfinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Ijj); (11) 3-({ [3-(benzothiophen-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Ikk); (12) (3S)-3-({[3-(l,3-dimethyl-l H-indd-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl} amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid ( I ); (13) 3-({ [3-(l,3-dimethyl-l H-indd-2-yl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Imm); (14) (35)-3-({[5-ethyl-3-(l-naphthylmethyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2,3,5,6-tetrafluorophenoxy)pentanoic acid ( Inn ); (15) (3S)-5-[(2,6-dichforobenzoyl)oxy]-3-[({5-ethyl-3-[2-(l-naphthyl)ethyl] - 4,5-dihydro-5-isoxazdyl }carbonyl)amino]-4-oxopentanoic acid (loo);

   (16) (35)-3-[({5-ethy+3-[(l-naphthytoxy)methyl] -

   4,5-dihydro-5-isoxazdyl]carbonyl)amino]-4-oxo-5-(2,3,5,6-tetrafluorophenoxy) pentanoic acid (Ipp);

   ( 17) (35)-3- { [(3- { [(4-chtoro- 1 -naphthyl)oxy ] methyl}-5-ethyl-4,5-dihydro-5-isoxazdyl)carbonyl]amino}-4-oxo-5-(2,3,5,6-tetr afluorophenoxy)pentanoic acid (Iqq);

   (18) (3S,4£)-6-ethoxy-3-({ [(5/?

   )-5-isopropyl-3-( 1 -isoquincfinyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-6-o xo-4-hexenoic acid (Irr);

   (19) (3S,4E)-3-({[(5i?)-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amiπo)-5-(methylsdfonyl)-4-pentenoic acid (Iss);

   (20) 5-f ιoro-3-( { [(5 S)-3-( 1 -isoquinolinyl)-5-propyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxopentanoic acid (Itt);

   (21 ) 3-({ [(5S)-5-ethyl-3-( 1 -naphthyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-f!uoro-4-oxopentanoic acid (Iuu);

   (22) 3-({ [(55)-5-ethyl-3-(2-quindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Ivv);

   (23) 3-( { [(5fl)-5-ethyl-3-(3-isoquinofinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iww);

   (24) 3-({ [5-ethyl-3-(8-quinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Ixx);

   (25) 3-({ [5-ethyl-3-(3-quinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fhoro-4-oxopentanoic acid (Iyy);

   (26) 5-fluoro-3-({ [(5 ?)-5-isopropyt3-(2-quinoBnyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxopentanoic acid (Izz);

   (27) 3-({ [5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaal);

   (28) 3-[({3-[3-(fert-butyl)phenyl] - 5-ethyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa2);

   (29) 3-[({3-[4-(tert-butyl)phenyl] -

   5-ethyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid

   (Iaa3);

   (30) 5-fluoro-3-({[(5fl

   )-5-isopropyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-

   4-oxopentanoic acid (Iaa4);

   (31) 3-[({(5/?)-3-[3-(tert-butyl)phenyl]-5-isopropyl-4,5-dihydr o- 5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa5);

   (32) 3-{[(3-[l,l'-biphenyl]-3-y+5-isopropyl-4,5-dihydro-5-isoxazdyl)carbonyl] amino }-5-fluoro-4-oxopentanoic acid (Iaa6);

   (33) 3-({ [5-ethyl-3-(2-pyridinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaa7);

   (34) 3-[({3-[4-( /-t-butyl)-2-pyridinyl] -

   5-ethyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa8);

   (35) 3-[({(5/?)-3-[4-(tert-butyl)-2-pyridinyl] -

   5-isopropyl-4,5-dihydro-5-isoxazdyl}carbonyl)amino]-5-fluoro-4-oxopentanoic acid (Iaa9);

   (36) 3-({ [5-ethyl-3-(4-isobutyl-2-pyridinyl)-4,5-dihydro -5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaa 10);

   (37) 3-( { [3-(4-acetyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaal l);

   (38) 3-( { [3-(4-cyctopropy+2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaal2);

   (39) 3-( { [3-(4-cyctopentyl-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaa 13); (40) 3-({[(5R

   )-3-(4-cyctopentyl-2-pyridinyl)-5-isopropyl-4,5-dihydro-5-isoxazdyl]carbonyl}a mino)-5-fluoro-4-oxopentanoic acid (Iaal4);

   (41 ) 3-( { [3-(4-cyctohexyI-2-pyridinyl)-5-ethyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fluoro-4-oxopentanoic acid (Iaal5);

   (42) 3-({[5-ethyl-3-(5,6,7,8-tetrahydro-l-isoquindinyl)-4,5-dihydro-5-isoxazdyl ]carbonyl}amino)-5-fluoro-4-oxopentanoic acid (Iaa 16); (43)

   5-fluoro-3-({[5-isopropyl-3-(4-phenyl-2-pyridinyl)-4,5-dihydro-5-isoxazdyl]car bonyl}amino)-4-oxopentanoic acid (Iaa 17);

   (44) (35)-5-[(diphenylphosphoryl)oxy]-3-({ [(5R

   )-5-isopropyl-3-( 1 -isoquincfinyl)-4,5-dihydro-5-isoxazdyrjcarbonyl } amino)-4-o xopentanoic acid (Iaa 18);

   (45) (35)-3-({[(5R)-5-isoρroρyl-3-(l-isoquindinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5- { [ l-pheny+3-(trifkoromethyl)-l H-pyrazd-5-yl] oxy}pentanoic acid (Iaal9);

   (46) (35)-5-[(4-benzy+5-oxo-2,5-dihydro-3-furanyl)oxy-3-({[(5 R )-5-isopropy+3-( 1 -isoquinoϊnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-o xopentanoic acid (Iaa20);

   (47) (35)-5-(isobutyrytoxy)-3-({[(5 R

   )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-o xopentanoic acid (Iaa21);

   (48) (3 )-3-({[(5R)-5-isopropyl-3-(l-isoquino]inyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-hexenoic acid (Iaa22);

   (49) (3S)-3-({[(5_JR)-5-isoρropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2-pyridinytoxy)pentanoic acid (Iaa23); (50) (35)-3-({[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-4-oxo-5-(2-pyridinytoxy)pentanoic acid (Iaa24);

   (51) 2-{[(35)-4-carboxy-3-({[(5/?

   )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-2-o xobutyl]oxy}-l-methylpyridinium trifluoromethanesdfonate (Iaa25);

   (52) 2-{[(35

   )-4-carboxy-3-({[5-ethyl-3-(2-isopropylphenyl)-4,5-dihydro-5-isoxazdyl]carbon yl } amino)-2-oxobutyl]oxy } - 1 -methylpyridinium trifluoromethanesdfonate

   (Iaa26);

   (53) 3-({[3-(5-chtoro-l-methyl-l H - indd-2-yl)-5-isopropyl-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-5-fluoro-4-ox opentanoic acid (Iaa27);

   (54) 3-({ [3-(l,5-dimethyl-l H-indd-2-yl)-5-isoρropyl-4,5-dihydro-5-isoxazdyl] carbonyl }amino)-5-fiuoro-4-oxopentanoic acid (Iaa28); and (55) (3S)-5-fluoro-3-({[(5R )-5-isopropyl-3-(l-isoquinofinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-o xopentanoic acid (Iii-1). [10] 8. The compound according to claim 1 which is 5-fluoro-3-({ [(5 R )-5-isopropyl-3-(l-isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl}amino)-4-o xopentanoic acid (Iii). [11] 9. A compound of the following formda (la):

   [13] (la) in which . 1 A, B, R, R , R^", and X are defined as described in claim 1.

   [14] 10. The compound according to claim 9 which is (35)-5-fluoro-3-( { [(5 R )-5-isopropyl-3-( 1 -isoquinoϋnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-o xopentanoic acid (Iii-1).

   [15] 11. A process for preparing the compound (Iii-1) as defined in claim 10, which comprises the steps of dissdving a mixture of (35)-5-ftuoro-3-({[(5R )-5-isopropyl-3-( 1 -isoquinoBnyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-o xopentanoic acid and (3/?)-5-fluoro-3-({[(5.# )-5-isopropyl-3-( 1 -isoquinolinyl)-4,5-dihydro-5-isoxazdyl]carbonyl } amino)-4-o xopentanoic acid in methyl t-butyl ether, adding a smal amount of crystalline (3 S)-5-fluoro-3-( { [(5 R)-5-isopropyl-3-( 1 -isoquinolinyl)-4,5-dihydro-5-isoxazdyl]c arbonyl}amino)-4-oxopentanoic acid as a seed materid to give a crystd, and re- crystalizing this crystd from ethyl acetate/n-hexane sdvent system.

   [16] 12. A therapeutic composition for preventing inflammation and apoptosis comprising the caspase inhibitor compound of formda (1), sdt, or stereoisomer thereof as defined in claim 1 as an active ingredient together with the pharmaceuticaly acceptaHe carrier.

   [17] 13. The composition according to claim 12 for the treatment of dementia, cerebral stroke, brain impairment due to AIDS, diabetes, gastric deer, cerebrd injure by hepatitis, hepatitis-induced hepatic diseases, acute hepatitis, fdminant hepatic failure, liver cirrhosis, sepsis, organ transplantation rejection, rheumatic arthritis, or cardiac eel apoptosis due to ischemic cardiac diseases.

   [18] 14. The composition according to claim 12 for the treatment of acute hepatitis or liver cirrhosis. [19] 15. The composition according to claim 12 for the treatment of rheumatic * arthritis.

   [20] 16. The composition according to claim 12 which is formdated as an ord preparation, an injection, or a patch.

   [21] 17. The composition according to claim 12 comprising the compound (Iii) as defined in claim 8 as an active ingredient.

   [22] 18. The composition according to claim 12 comprising the compound (Iii-1) as defined in claim 10 as an active ingredient.

   [23] 19. A process for preparing the therapeutic composition for preventing inflammation and apoptosis as defined in claim 12, comprising admixing the caspase inhibitor compound of formda (1), sdt, or stereoisomer thereof as defined in claim 1 with pharmaceuticaly acceptaHe carrier.

   [24] 20. A method for preventing inflammation and apoptosis, comprising administering an effective amount of the caspase inhibitor compound of formda (1), salt, or stereoisomer thereof as defined in claim 1 to a patient suffering from inflammation and apoptosis.

   [25] 21. A use of the caspase inhibitor compound of formda (1), sdt, or stereoisomer thereof as defined in claim 1 for preventing inflammation and apoptosis.