Substituted acid derivatives useful as antidiabetic and antiobesity agents and method Number:7,084,162 from the United States Patent and Trademark Office (PTO) owispatent Compounds are provided which have the structure ##STR00001## wherein Q is C or N, A is O or S, Z is O or a bond, X is CH or N and R.sup.1, R.sup.2, R.sup.2a, R.sup.2b, R.sup.2c, R.sup.3, Y, x, m, and n are as defined herein, which compounds are useful as antidiabetic, hypolipidemic, and antiobesity agents.<H antidiabetic, antiobesity, Substituted, aci, 7084162.html, Patent, pto, 7084162

Title: Substituted acid derivatives useful as antidiabetic and antiobesity agents and method

Abstract: Compounds are provided which have the structure ##STR00001## wherein Q is C or N, A is O or S, Z is O or a bond, X is CH or N and R.sup.1, R.sup.2, R.sup.2a, R.sup.2b, R.sup.2c, R.sup.3, Y, x, m, and n are as defined herein, which compounds are useful as antidiabetic, hypolipidemic, and antiobesity agents.

Patent Number: 7,084,162 Issued on 08/01/2006 to Cheng, et al.

Inventors: Cheng; Peter T. (Princeton, NJ); Devasthale; Pratik (Plainsboro, NJ); Jeon; Yoon (Belle Mead, NJ); Chen; Sean (Princeton, NJ); Zhang; Hao (Belle Mead, NJ)
Assignee: Bristol-Myers Squibb Company (Princeton, NJ)

Appl. No.: 10/655,876

Filed: September 5, 2003

Related U.S. Patent Documents


Application Number	Filing Date	Patent Number	Issue Date
10080981	Feb., 2002	6653314
09812960	Mar., 2001	6414002
09664598	Sep., 2000
60155400	Sep., 1999

Current U.S. Class: 514/374 ; 548/236

Current International Class: A61K 31/421 (20060101); C07D 263/32 (20060101)

Field of Search: 548/236

References Cited [Referenced By]

U.S. Patent Documents


5036079	July 1991	Clark et al.
5889025	March 1999	Lohray et al.

Foreign Patent Documents


0520723	Jun., 1994	EP
WO92/22533	Dec., 1992	WO
WO96/38415	Dec., 1996	WO
WO97/27847	Aug., 1997	WO
WO97/27857	Aug., 1997	WO
WO97/28137	Aug., 1997	WO
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WO98/00403	Jan., 1998	WO
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WO99/07357	Feb., 1999	WO
WO99/08501	Feb., 1999	WO
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Other References

Collins, et al, J. Med. Chem., 41, 5037-5054, 1998. cited by other .
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Primary Examiner: Richter; Johann
Assistant Examiner: Sackey; Ebenezer
Attorney, Agent or Firm: Rodney; Burton

Parent Case Text

This is a divisional application of application Ser. No. 10/080,981 filed Feb. 22, 2002 now U.S. Pat. No. 6,653,314 which is a continuation of application Ser. No. 09/812,960 filed Mar. 20, 2001 , now U.S. Pat. No. 6,414,002, which is a continuation-in-part of U.S. application Ser. No. 09/664,598 filed Sep. 18, 2000, now abandoned, which application takes priority from U.S. provisional application No. 60/155,400 filed Sep. 22, 1999.

Claims

What is claimed is:

1. A compound having the structure amino ester (a) ##STR00974## or amino acid (b) ##STR00975## wherein PG is a carboxylic acid protecting group which is methyl, ethyl or t-butyl, and ##STR00976## wherein X.sup.1.sub.x is an alkylene chain of two carbons, alkenylene chain of two carbons or an alkynylene chain of two carbons; X.sup.1.sub.m is an alkylene chain of one carbon; and X.sup.1.sub.n is an alkylene chain of one carbon; Q is C; A is O; R.sup.1 is methyl; X is CH; R.sup.2 is H, alkyl, alkoxy, halogen, amino or substituted amino; R.sup.2a, R.sup.2b and R.sup.2c are each H; or stereoisomers thereof, or a prodrug ester thereof, and pharmaceutically acceptable salt thereof.

2. The compound as defined in claim 1 wherein X.sup.1.sub.x is (CH.sub.2).sub.2; X.sup.1.sub.m is CH.sub.2, or ##STR00977## wherein R.sub.a is or alkyl alkenyl, X.sup.1.sub.n is CH.sub.2, R.sup.1 is lower alkyl, R.sup.2a H, .sup.4X is CH; and PG is methyl, ethyl or t-butyl.

3. The compound as defined in claim 1 having the structure ##STR00978##

Description

FIELD OF THE INVENTION

The present invention relates to novel substituted acid derivatives which modulate blood glucose levels, triglyceride levels, insulin levels and non-esterified fatty acid (NEFA) levels, and thus are particularly useful in the treatment of diabetes and obesity, and to a method for treating diabetes, especially Type 2 diabetes, as well as hyperglycemia, hyperinsulinemia, hyperlipidemia, obesity, atherosclerosis and related diseases employing such substituted acid derivatives alone or in combination with another antidiabetic agent and/or a hypolipidemic agent.

DESCRIPTION OF THE INVENTION

In accordance with the present invention, substituted acid derivatives are provided which have the structure I ##STR00002## wherein x is 1, 2, 3 or 4; m is 1 or 2; n is 1 or 2;

Q is C or N;

A is O or S;

Z is O or a bond;

R.sup.1 is H or alkyl;

X is CH or N;

R.sup.2 is H, alkyl, alkoxy, halogen, amino or substituted amino;

R.sup.2a, R.sup.2b and R.sup.2c may be the same or different and are selected from H, alkyl, alkoxy, halogen, amino or substituted amino;

R.sup.3 is H, alkyl, arylalkyl, aryloxycarbonyl, alkyloxycarbonyl, alkynyloxycarbonyl, alkenyloxycarbonyl, arylcarbonyl, alkylcarbonyl, aryl, heteroaryl, alkyl(halo)aryloxycarbonyl, alkyloxy(halo)aryloxycarbonyl, cycloalkylaryloxycarbonyl, cycloalkyloxyaryloxycarbonyl, cycloheteroalkyl, heteroarylcarbonyl, heteroaryl-heteroarylalkyl, alkylcarbonylamino, arylcarbonylamino, heteroarylcarbonylamino, alkoxycarbonylamino, aryloxycarbonylamino, heteroaryloxycarbonylamino, heteroaryl-heteroarylcarbonyl, alkylsulfonyl, alkenylsulfonyl, heteroaryloxycarbonyl, cycloheteroalkyloxycarbonyl, heteroarylalkyl, aminocarbonyl, substituted aminocarbonyl, alkylaminocarbonyl, arylaminocarbonyl, heteroarylalkenyl, cycloheteroalkyl-heteroarylalkyl; hydroxyalkyl, alkoxy, alkoxyaryloxycarbonyl, arylalkyloxycarbonyl, alkylaryloxycarbonyl, arylheteroarylalkyl, arylalkylarylalkyl, aryloxyarylalkyl, haloalkoxyaryloxycarbonyl, alkoxycarbonylaryloxycarbonyl, aryloxyaryloxycarbonyl, arylsulfinylarylcarbonyl, arylthioarylcarbonyl, alkoxycarbonylaryloxycarbonyl, arylalkenyloxycarbonyl, heteroaryloxyarylalkyl, aryloxyarylcarbonyl, aryloxyarylalkyloxycarbonyl, arylalkenyloxycarbonyl, arylalkylcarbonyl, aryloxyalkyloxycarbonyl, arylalkylsulfonyl, arylthiocarbonyl, arylalkenylsulfonyl, heteroarylsulfonyl, arylsulfonyl, alkoxyarylalkyl, heteroarylalkoxycarbonyl, arylheteroarylalkyl, alkoxyarylcarbonyl, aryloxyheteroarylalkyl, heteroarylalkyloxyarylalkyl, arylarylalkyl, arylalkenylarylalkyl, arylalkoxyarylalkyl, arylcarbonylarylalkyl, alkylaryloxyarylalkyl, arylalkoxycarbonylheteroarylalkyl, heteroarylarylalkyl, arylcarbonylheteroarylalkyl, heteroaryloxyarylalkyl, arylalkenylheteroarylalkyl, arylaminoarylalkyl, aminocarbonylarylarylalkyl;

Y is CO.sub.2R.sup.4 (where R.sup.4 is H or alkyl, or a prodrug ester) or Y is a C-linked 1-tetrazole, a phosphinic acid of the structure P(O)(OR.sup.4a)R.sup.5, (where R.sup.4a is H or a prodrug ester, R.sup.5 is alkyl or aryl) or phosphonic acid of the structure P(O)(OR.sup.4a).sub.2, (where R.sup.4a is H or a prodrug ester);

X.sup.1.sub.x, X.sup.1.sub.n and X.sup.1.sub.m which may also be referred to as (CH.sub.2).sub.x, (CH.sub.2).sub.n and (CH.sub.2).sub.m, respectively, may be optionally substituted with 1, 2 or 3 substituents;

including all stereoisomers thereof, prodrug esters thereof, and pharmaceutically acceptable salts thereof, with the proviso that

where X is CH, A is O, Q is C, Z is O, and Y is CO.sub.2R.sup.4, then R.sup.3 is other than H or alkyl containing 1 to 5 carbons in the normal chain.

Thus, compounds of formula I of the invention may have the structure ##STR00003##

Preferred are compounds of formula I of the invention having the structure ##STR00004##

More preferred are compounds of formula I of the invention having the structures ##STR00005##

In the above compounds, it is most preferred that R.sup.2a is alkoxy, but more preferably H, Z is a bond, but more preferably O, X.sup.1.sub.x or (CH.sub.2).sub.x is CH.sub.2, (CH.sub.2).sub.2, (CH.sub.2).sub.3, or ##STR00006## X.sup.1.sub.m or (CH.sub.2).sub.m is CH.sub.2, or ##STR00007## (where R.sub.a is alkyl such as methyl, or alkenyl such as ##STR00008## ), X.sup.1.sub.n or (CH.sub.2).sub.n is CH.sub.2, R.sup.1 is lower alkyl, preferably --CH.sub.3, R.sup.2 is H, R.sup.2a is H, R.sup.4 is H, X is CH, and R.sup.3 is arylalkyloxycarbonyl, arylheteroarylalkyl, aryloxyarylalkyl, arylalkyl, aryloxycarbonyl, haloaryloxycarbonyl, alkoxyaryloxycarbonyl, alkylaryloxycarbonyl, aryloxyaryloxycarbonyl, heteroaryloxyarylalkyl, heteroaryloxycarbonyl, aryloxyarylcarbonyl, arylalkenyloxycarbonyl, cycloalkylaryloxycarbonyl, arylalkylarylcarbonyl, heteroaryl-heteroarylalkyl, cycloalkyloxyaryloxycarbonyl, heteroaryl-heteroarylcarbonyl, alkyloxyaryloxycarbonyl, arylalkylsulfonyl, arylalkenylsulfonyl, alkoxyarylalkyl, arylthiocarbonyl, cycloheteroalkylalkyloxycarbonyl, cycloheteroalkyloxycarbonyl, or polyhaloalkylaryloxycarbonyl, wherein the above preferred groups may be optionally substituted.

Preferred compounds of the invention include the following: ##STR00009## ##STR00010## ##STR00011## ##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016## ##STR00017## ##STR00018## ##STR00019## ##STR00020## ##STR00021## ##STR00022## ##STR00023## ##STR00024## ##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029## ##STR00030## ##STR00031## ##STR00032## ##STR00033##

In addition, in accordance with the present invention, a method is provided for treating diabetes, especially Type 2 diabetes, and related diseases such as insulin resistance, hyperglycemia, hyperinsulinemia, elevated blood levels of fatty acids or glycerol, hyperlipidemia, obesity, hypertriglyceridemia, inflammation, Syndrome X, diabetic complications, dysmetabolic syndrome, atherosclerosis, and related diseases wherein a therapeutically effective amount of a compound of structure I is administered to a human patient in need of treatment.

In addition, in accordance with the present invention, a method is provided for treating early malignant lesions (such as ductal carcinoma in situ of the breast and lobular carcinoma in situ of the breast), premalignant lesions (such as fibroadenoma of the breast and prostatic intraepithelial neoplasia (PIN), liposarcomas and various other epithelial tumors (including breast, prostate, colon, ovarian, gastric and lung), irritable bowel syndrome, Crohn's disease, gastric ulceritis, and osteoporosis and proliferative diseases such as psoriasis, wherein a therapeutically effective amount of a compound of structure I is administered to a human patient in need of treatment.

In addition, in accordance with the present invention, a method is provided for treating diabetes and related diseases as defined above and hereinafter, wherein a therapeutically effective amount of a combination of a compound of structure I and another type antidiabetic agent and/or a hypolipidemic agent, and/or lipid modulating agent and/or other type of therapeutic agent, is administered to a human patient in need of treatment.

In the above methods of the invention, the compound of structure I will be employed in a weight ratio to the antidiabetic agent (depending upon its mode of operation) within the range from about 0.01:1 to about 100:1, preferably from about 0.5:1 to about 10:1.

The conditions, diseases, and maladies collectively referenced to as "Syndrome X" or Dysmetabolic Syndrome are detailed in Johannsson J. Clin. Endocrinol. Metab., 82, 727-734 (1997) and other publications.

The term "diabetes and related diseases" refers to Type II diabetes, Type I diabetes, impaired glucose tolerance, obesity, hyperglycemia, Syndrome X, dysmetabolic syndrome, diabetic complications and hyperinsulinemia.

The conditions, diseases and maladies collectively referred to as "diabetic complications" include retinopathy, neuropathy and nephropathy, and other known complications of diabetes.

The term "other type(s) of therapeutic agents" as employed herein refers to one or more antidiabetic agents (other than compounds of formula I), one or more anti-obesity agents, and/or one or more lipid-lowering agents, one or more lipid modulating agents (including anti-atherosclerosis agents), and/or one or more antiplatelet agents, one or more agents for treating hypertension, one or more anti-cancer drugs, one or more agents for treating arthritis, one or more anti-osteoporosis agents, one or more anti-obesity agents, one or more agents for treating immunomodulatory diseases, and/or one or more agents for treating anorexia nervosa.

The term "lipid-modulating" agent as employed herein refers to agents which lower LDL and/or raise HDL and/or lower triglycerides and/or lower total cholesterol and/or other known mechanisms for therapeutically treating lipid disorders.

DETAILED DESCRIPTION OF THE INVENTION

The compounds of the formula I of the present invention may be prepared according to the following general synthetic schemes, as well as relevant published literature procedures that are used by one skilled in the art. Exemplary reagents and procedures for these reactions appear hereinafter and in the working Examples. Protection and deprotection in the Schemes below may be carried out by procedures generally known in the art (see, for example, Greene, T. W. and Wuts, P. G. M., Protecting Groups in Organic Synthesis, 3.sup.rd Edition, 1999 [Wiley]).

Scheme 1 describes a general synthesis of the amino acids described in this invention. An alcohol II (R.sup.5(CH.sub.2).sub.xOH) (of which the most favored is 2-phenyl-5-methyl-oxazole-4-ethanol) is coupled with a hydroxy aryl- or heteroaryl-aldehyde III (preferably 3- or 4-hydroxybenzaldehyde) under standard Mitsunobu reaction conditions (e.g. Mitsunobu, O., Synthesis, 1981, 1). The resulting aldehyde IV is then subjected to reductive amination using procedures known in the literature (e.g. Abdel-Magid et al, J. Org. Chem. 1996, 61, 3849) with an .alpha.-amino ester hydrochloride V. PG in Scheme 1 denotes a preferred carboxylic acid protecting group, such as a methyl or tert-butyl ester. The resulting secondary amino-ester VI is then subjected to a second reductive amination using methods known in the literature (e.g. Abdel-Magid et al, J. Org. Chem. 1996, 61, 3849) with an R.sup.3a aldehyde VII. Final deprotection of the carboxylic acid ester under standard conditions known in the literature (Greene) utilizing basic conditions (for methyl esters) or acidic conditions (for tert-butyl esters) then furnishes the desired amino acid products ID.

An alternative route to the aldehyde IV is shown in Scheme 1A. The alcohol II (R.sup.5(CH.sub.2).sub.nOH) (of which the most favored is 2-[2-phenyl-5-methyl-oxazole-4-yl]-ethanol) is treated with methanesulfonyl chloride to give the corresponding mesylate VIII. The mesylate is then alkylated under standard basic conditions with a hydroxyaryl or hydroxyheteroaryl aldehyde III to furnish the aldehyde IV.

An alternative route to the amino acids IF is shown in Scheme 2. The secondary amino-ester VI is deprotected under standard conditions (basic conditions if the protecting group (PG) is methyl; acidic conditions if PG is tert-butyl) to furnish the corresponding amino acid IE. Reductive amination with an R.sup.3a aldehyde under analogous conditions as described in Scheme 1 furnishes the desired tertiary amino acid products IF.

Alternatively, as shown in Scheme 3, the tertiary amino acids IF may also be obtained by alkylation of the secondary amino-ester VI with an alkylating agent IX (with an appropriate leaving group (LG) such as halide, mesylate, or tosylate) under standard conditions known in the art followed again by standard deprotection of the carboxylic acid ester X to provide the amino acids IF.

As shown in Scheme 4, the tertiary amino acid IF may also be assembled through reductive amination first of the R.sup.3a aldehyde XI with an appropriate amine ester hydrochloride V. The resulting secondary amine-ester XII then is subjected to reductive amination with the appropriate alkyl, aryl or heteroaryl aldehyde IV (as in Scheme 1) followed by deprotection of the carboxylic acid ester to give the desired amino acid analogs IF.

For further substituted amino acids, a general synthetic scheme is shown in Scheme 5. Reductive amination of an appropriate amine XIII with an aryl or heteroaryl aldehyde XIV under standard conditions furnishes the corresponding secondary amine XV, which is then reacted with a halide-ester XVI (e.g. tert-butyl bromoacetate) to furnish the corresponding .alpha.-amino ester XVII. This amine-ester XVII is then deprotected under standard conditions to provide the desired amino acid analogs IF.

The synthetic route in Scheme 5 also provides a general scheme for the synthesis of the corresponding aminophosphonic acids IFA, as illustrated in Scheme 5a. The secondary amine XV is reacted with an appropriately protected halide-phosphonate XVIA to provide the corresponding aminophosphonate ester XVIIA, which is then deprotected under standard conditions (Greene & Wuts) to furnish the amino phosphonic acid IFA. Scheme 5b illustrates the synthesis of the aminophosphinic acids IFB, which again involves the reaction of an appropriately protected halide-phosphinate ester XVIB with the secondary amine XV. Deprotection of the resulting aminophosphinate ester then provides the phosphinic acid IFB.

An alternative to the sequence in Scheme 5 is shown in Scheme 6. A hydroxyaryl or heteroaryl amine XVIII is selectively protected on nitrogen to provide protected amine XIX. A preferred R.sup.5(CH.sub.2).sub.nOH (II) is then reacted with XIX under Mitsunobu conditions to provide the corresponding ether, followed by deprotection of the amine, to form the free amine XX. The free amine XX is then activated with a standard activating group (2,4-dinitrobenzenesulfonamide; T. Fukuyama et al, Tetrahedron Lett. 1997, 38, 5831) and is then treated with an .alpha.-halo ester XVI as in Scheme 5. The 2,4 dinitrobenzenesulfonamide XXI is deprotected under literature conditions (T. Fukuyama et al, Tetrahedron Lett., 1997, 38, 5831) to furnish a secondary .alpha.-amino-ester XXII which is then subjected to a reductive amination with an R.sup.3a aldehyde XI followed by deprotection of the ester X to furnish the desired analogs IF.

Scheme 7 describes an alternative general route to the amino acid analogs IG. A hydroxyaryl or heteroaryl aldehyde III is subjected to the usual reductive amination conditions with an appropriate amine-ester hydrochloride V. The resulting secondary amine-ester XXIII is functionalized, in this case by a second reductive amination with an R.sup.3a aldehyde VII to furnish the corresponding hydroxy tertiary amine-ester XXIV. This can now undergo a Mitsunobu reaction with a preferred alcohol II (R.sup.5(CH.sub.2).sub.nOH) which followed by deprotection of the ester XXV furnishes the desired analogs IG.

Scheme 8 describes a general synthesis of diaryl and aryl-heteroaryl-substituted amino acid analogs IH. The secondary amine-ester XXII undergoes reductive amination with an appropriately substituted formyl phenyl boronic acid XXVI under standard conditions to give the corresponding tertiary amine-ester boronic acid XXVII. The aryl boronic acid XXVII can then undergo a Suzuki coupling (e.g. conditions as described in Gibson, S. E., Transition Metals in Organic Synthesis, A Practical Approach, pp. 47-50, 1997) with aryl or heteroaryl halides XXVIII (especially bromides) to furnish the appropriate cross-coupling diaryl products XXIX. Deprotection of the amine-ester XXIX generates the desired amino acid analogs IH.

Scheme 9 describes a general synthesis of diaryl and aryl-heteroaryl ether-substituted amino acid analogs IJ. The tertiary amine-ester boronic acid XXVII which is described in Scheme 8 can be coupled with appropriately substituted phenols XXX under literature conditions (D. A. Evans et al, Tetrahedron Lett., 1998, 39, 2937) to furnish the appropriate diaryl or aryl-heteroaryl ethers XXXI, which after deprotection afford the desired amino acid analogs IJ.

Alternatively, as shown in Scheme 10, reductive amination of the secondary amine-ester XXII with an appropriately substituted hydroxyaryl or hydroxyheteroaryl aldehyde XXXII furnishes the corresponding phenol-tertiary amine-ester XXXIII. The phenol XXXIII can then undergo coupling with appropriate aryl or heteroaryl boronic acids XXXIV under literature conditions (D. A. Evans et al, Tetrahedron Lett., 1998, 39, 2937) to furnish the corresponding diaryl or arylheteroaryl ether-amino esters XXXI. The desired analogs IJ are then obtained after deprotection of the amine-ester XXXI.

Scheme 11 illustrates the synthesis of the carbamate-acid analogs IK. The secondary amine-ester XXII can be reacted with appropriate chloroformates XXXV under standard literature conditions (optimally in CH.sub.2Cl.sub.2 or CHCl.sub.3 in the presence of a base such as Et.sub.3N) to furnish the corresponding carbamate-esters. The requisite analogs IK are then obtained after deprotection of the carbamate-ester. Alternatively, the secondary amine-ester XXII can be reacted with phosgene to generate the corresponding carbamyl chloride XXXVI. This carbamyl chloride intermediate XXXVI can be reacted with R.sup.3a--OH (XXXVII)(optimally substituted phenols) to afford the corresponding carbamate-acids IK after deprotection.

Scheme 12 illustrates the further functionalization of aryl carbamate-acid analogs IK. The secondary amine-ester XXII is reacted with an aryl chloroformate XXXVIII (containing a protected hydroxyl group) to form XXXIX. The hydroxyl group is then selectively deprotected in the presence of the ester functionality to provide XL, then alkylated with an appropriate R.sup.6-LG (XLI) (where LG is halide, mesylate or tosylate, and R.sup.6 is most preferably CHF.sub.2--, or CH.sub.3CH.sub.2--) in the presence of base. Deprotection of the ester then furnishes the desired carbamate-acid analogs IL.

The secondary amine-ester XXIIA can be functionalized with substituted aryl or aliphatic carboxylic acids XLII, under standard peptide coupling conditions, as illustrated in Scheme 13. The amide bond-forming reactions are conducted under standard peptide coupling procedures known in the art. Optimally, the reaction is conducted in a solvent such as DMF at 0.degree. C. to RT using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDAC or EDCI or WSC), 1-hydroxybenzotriazole (HOBT) or 1-hydroxy-7-azabenzotriazole (HOAT) and a base, for example Hunig's base (diisopropylethylamine), N-methyl morpholine or triethylamine. Deprotection of the amide-ester then furnishes the desired amide-acid analogs IM.

The secondary amine-ester XXIIA can also be reacted with aliphatic or aryl isocyanates XLIII to provide the corresponding urea-esters. Deprotection of the urea-ester provides the desired urea-acid analogs IN, as shown in Scheme 14. Alternatively, as shown in Scheme 15, the carbamyl chloride intermediate XXXVI described in Scheme 11 can be reacted with appropriate aliphatic or aryl amines XLIV in the presence of a tertiary amine (e.g. Et.sub.3N) to furnish tri- or tetrasubstituted urea-acid analogs IO or IP after deprotection of the ester.

The secondary amine-ester XXIIA can also be reacted with appropriate sulfonyl chlorides XLVI under standard literature conditions (optimally in the presence of a base such as pyridine, either neat or using chloroform as a co-solvent), followed by deprotection, to provide the corresponding sulfonamide-acids IQ, as shown in Scheme 16.

Replacement of the carboxylic acid functionality in these analogs with tetrazole can be achieved as shown in Scheme 17. An acid analog IK is coupled with an amine (containing an appropriate tetrazole protecting group) XLVII (preferably 3-amino propionitrile) under standard peptide coupling conditions. The resulting secondary amide XLVIII is then subjected to a Mitsunobu reaction under standard conditions with trimethylsilyl azide (TMSN.sub.3) to form the protected tetrazole XLIX. Deprotection of the cyanoethyl group is achieved preferentially in the presence of base to generate the desired free tetrazole analog IR.

Scheme 18 describes a general synthesis of the hydrazide-acid analogs IS. A substituted aryl carboxylic acid 1 is treated with methanesulfonyl chloride in the presence of base; the intermediate is then reacted with a protected hydrazine-ester VA to give the corresponding acylated hydrazine 1a (ref: Synthesis, 1989, 745-747). The acylhydrazine 1a is coupled with an appropriately substituted aryl aldehyde IV under reductive amination conditions to give the corresponding protected hydrazide ester 3 (ref: Can. J. Chem., 1998, 76, 1180-1187). Deprotection of the ester 3 then furnishes the hydrazide-acid analogs IS.

An alternative synthetic approach to hydrazide-acids IS is shown in Scheme 19. An aryl aldehyde IV can be reduced to the corresponding alcohol under standard conditions (e.g NaBH.sub.4). This alcohol is then converted to the corresponding bromide 4 using standard conditions (e.g. Ph.sub.3P/CBr.sub.4 or PBr.sub.3). The bromide 4 is then reacted with the hydrazine-ester 1a (ref: Tetrahedron Lett., 1993, 34, 207-210) to furnish the protected hydrazide-ester 3, which is then deprotected to give the hydrazide-acid analogs IS.

The different approaches to the preparation of the .alpha.-alkylbenzyl amino acid and carbamate-acid analogs IT and IU are exemplified in the following synthetic schemes. In Scheme 20 an appropriately substituted aryl aldehyde IV is treated with a suitable organometallic reagent (e.g. a Grignard reagent R.sup.10MgBr) under standard conditions to give the corresponding secondary alcohol, which is then oxidized under standard conditions (e.g. Swern oxidation with (COCl).sub.2/DMSO/Et.sub.3N or using pyridinium chlorochromate) to give the corresponding ketone 5. Reductive amination of the ketone 5 with an appropriately substituted amino-ester 6 provides the corresponding .alpha.-alkylbenzyl amino-ester 7. It will be understood that in the amino ester 6, the moiety ##STR00034## does not necessarily represent two repeating units.

Acylation of amino-ester 7 with an appropriately substituted aryl or heteroaryl chloroformate XXXV followed by deprotection provides the racemic carbamate-acid analogs IT. Reductive amination of alkylbenzyl amino-ester 7 with aryl aldehyde VII followed by deprotection provides the racemic amino-acid analogs IU.

Alternatively, as shown in Scheme 21, asymmetric reduction (e.g. using the Corey oxazaborolidine reduction protocol; review: E. J. Corey & C. Helal, Angew. Chem. Int. Ed. Engl., 1998, 37, 1986-2012.) of the aryl-ketone 5 provides each of the desired enantiomeric alcohols 8 (although only one enantiomer is represented in the scheme). Treatment of the chiral alcohol 8 with azide in a Mitsunobu-like reaction (ref: A. S. Thompson et. al., J. Org. Chem. 1993, 58, 5886-5888) gives the corresponding chiral azide (with inverted stereochemistry from the starting alcohol). The azide is then converted to the amine 9 by standard reduction methods (e.g. hydrogenation or Ph.sub.3P/THF/H.sub.2O). Treatment of the chiral amine 9 with an ester XVIA (containing an appropriate leaving group) provides the secondary amino-ester 10. Acylation of amino-ester 10 with an aryl or heteroaryl chloroformate XXXV followed by deprotection provides the chiral carbamate-acid analogs ITa (which may be either enantiomer depending upon the stereochemistry of 8). Reductive amination of alkyl amino-ester 10 with aryl aldehydes VII followed by deprotection provides the chiral amino-acid analogs IUa (which may be either enantiomer depending upon the stereochemistry of 8).

An alternative to Scheme 21 is shown in Scheme 22. An appropriately protected oxyaryl ketone 11 undergoes asymmetric reduction to give the chiral alcohol 12. This is converted to the chiral amine 13 via the identical sequence as in Scheme 21 (via the chiral azide). Treatment of the chiral amine 13 with an ester XVIA (LG=halogen or mesylate) gives the corresponding secondary amino-ester 14. Acylation of 14 with an aryl or heteroaryl chloroformate XXXV provides the corresponding carbamate-ester. Selective deprotection furnishes the free phenol carbamate-ester 15. Alkylation of the phenol 15 with a halide or mesylate VIII followed by deprotection provides the carbamate-acid analogs ITa. An analogous sequence (involving reductive amination of the secondary amino-ester 14 with an aryl or heteroaryl aldehyde VII, then selective deprotection, alkylation with VIII and a final deprotection) provides the amino acid analogs IUa.

It will be appreciated that either the (R)- or (S)-enantiomer of ITa or IUa may be synthesized in Schemes 21 and 22, depending upon the chirality of the reducing agent employed.

A fourth synthetic sequence is shown in Scheme 23. The substituted aldehyde IV is condensed with an amino-ester hydrochloride 6 to give the corresponding imine 16, which is then treated in situ with an appropriately substituted allylic halide 17 in the presence of indium metal (reference: Loh, T.-P., et al., Tetrahedron Lett., 1997, 38, 865-868) to give the .alpha.-allyl benzyl amino-ester 18. Acylation of amine 18 with an aryl or heteroaryl chloroformate XXXV followed by deprotection provides the carbamate-acid analogs Iv. Reductive amination of alkyl amino-ester 18 with an aryl or heteroaryl aldehyde VII followed by deprotection provides the amino-acid analogs IW.

Scheme 24 shows the preparation of the required intermediate 2-aryl-5-methyl-oxazol-4-yl methyl chloride 21 (following the general procedure described in Malamas, M. S., et al, J. Med. Chem., 1996, 39, 237-245). A substituted aryl aldehyde 19 is condensed with butane-2,3-dione mono-oxime under acidic conditions to give the corresponding oxazole N-oxide 20. Deoxygenation of the oxazole N-oxide 20 with concomitant chlorination furnishes the desired chloromethyl aryl-oxazoles 21. Hydrolysis of chloromethyl oxazole 21 under basic conditions furnishes the corresponding oxazole-methanol 22. Oxidation of alcohol 22 to the corresponding aldehyde is followed by conversion to the corresponding dibromoalkene 23 (e.g. Ph.sub.3P/CBr.sub.4). The dibromide 23 is converted to the corresponding alkynyl-lithium species (using an organolithium reagent such as n-BuLi), which can be reacted in situ with an appropriate electrophile such as formaldehyde to give the corresponding acetylenic alcohol (ref: Corey, E. J., et al., Tetrahedron Lett. 1972, 3769, or Gangakhedkar, K. K., Synth. Commun. 1996, 26, 1887-1896). This alcohol can then be converted to the corresponding mesylate 24 and alkylated with an appropriate phenol 25 to provide analogs Ix. Further stereoselective reduction (e.g. H.sub.2/Lindlar's catalyst) provides the E- or Z-alkenyl analogs IY.

Scheme 25 describes a general synthesis of the amino-benzoxazole analogs IZ (general ref: Sato, Y., et al, J. Med. Chem. 1998, 41, 3015-3021). An appropriately substituted ortho-aminophenol 26 is treated with CS.sub.2 in the presence of base to furnish the corresponding mercapto-benzoxazole 27. Treatment of this thiol 27 with an appropriate chlorinating agent (e.g. PCl.sub.5) provides the key intermediate chlorobenzoxazole 28, which is reacted with the secondary amino-ester VI to furnish, after deprotection, the amino benzoxazole-acid analogs IZ.

The thiazole analogs IZa were synthesized according to the general synthetic route outlined in Scheme 26 (ref. Collins, J. L., et al., J. Med. Chem. 1998, 41, 5037). The secondary amino-ester XXIII is reacted with an aryl or heteroaryl chloroformate XXXV in the presence of an appropriate base (e.g. pyridine or triethylamine) to furnish the corresponding hydroxyaryl carbamate-ester 29. The hydroxyaryl ester 29 is then reacted with an appropriately substituted .alpha.-bromo vinyl ketone 29a (for S.sub.3.dbd.CH.sub.3, e.g. Weyerstahl, P., et. al., Flavour Fragr. J., 1998, 13, 177 or Sokolov, N. A., et al., Zh. Org. Khim., 1980, 16, 281-283) in the presence of an appropriate base (e.g. K.sub.2CO.sub.3) to give the corresponding Michael reaction adduct, the .alpha.-bromoketone carbamate-ester 30. The .alpha.-bromoketone 30 is then subjected to a condensation reaction with an appropriately substituted aryl amide 31 (A.dbd.O) or aryl thioamide 31 (A.dbd.S) to furnish either the corresponding oxazole (from the amide) or the thiazole (from the thioamide) (ref: Malamas, M. S., et al, J. Med. Chem., 1996, 39, 237-245). Finally, deprotection of esters 31 then provides the substituted oxazole and thiazole carbamate acid analogs IZa.

It will be appreciated that in the following schemes where the carbamate-acid analogs are prepared, the corresponding amino acid analogs may also be prepared by replacing the chloroformate reaction with an aldehyde in a reductive amination reaction (as in Scheme 20 with intermediate amine 7).

Scheme 27 describes a general synthesis of the acids IZb and IZc. A halo-substituted aryl aldehyde 32 (preferably iodide or bromide) is subjected to reductive amination using procedures known in the literature (e.g. Abdel-Magid et al, J. Org. Chem. 1996, 61, 3849) with an .alpha.-amino acid ester hydrochloride V. The resulting secondary amino-ester 33 is then reacted with an aryl or heteroaryl chloroformate XXXV in the presence of an appropriate base (e.g. pyridine or triethylamine) to furnish the corresponding halo-aryl carbamate-ester 34. Aryl halide 34 is then reacted with an appropriate aryl- or heteroaryl-substituted acetylene 35 (the preferred acetylene being 5-phenyl-2-methyl-oxazol-4-yl-methylacetylene) in the presence of an appropriate palladium catalyst (e.g. (Ph.sub.3P).sub.2PdCl.sub.2) and a copper (I) salt (e.g. CuI) in a Sonogashira coupling reaction (ref: Organocopper Reagents, a Practical Approach, R. J. K. Taylor, Ed., Chapter 10, pp 217-236, Campbell, I. B., Oxford University Press, 1994) to furnish the key intermediate, arylacetylene carbamate ester 36.

The arylacetylene ester 36 is deprotected to provide the corresponding arylacetylene acid analogs IZb. The acetylene moiety of 36 can be reduced by standard methods (e.g. hydrogenation, ref: M. Hudlicky, Reductions in Organic Chemistry, 2.sup.nd Edition, ACS, 1996, Chapter 1) to furnish the corresponding fully saturated alkyl aryl carbamate ester, which is then deprotected to give the alkyl aryl carbamate acid analogs IZc.

Stereoselective reduction of the acetylene ester 36 by standard methods (e.g. Lindlar's catalyst; ref: Preparation of Alkenes, A Practical Approach, J. J. Williams, Ed., Chapter 6, pp 117-136, Oxford University Press, 1996) can be achieved to provide the corresponding cis-alkenyl aryl carbamate-ester, which is then deprotected to furnish the Z-alkenyl aryl carbamate acid analogs IZd (Scheme 28). Alternatively, this sequence can be reversed, i.e. the initial step being the deprotection of acetylenic ester 36 to the acetylenic acid, followed by stereoselective reduction of the acetylene moiety to provide the Z-alkene-acid analogs IZd.

The corresponding trans-alkenyl aryl carbamate acids IZe can be synthesized according to the general route in Scheme 29. An aryl- or heteroaryl-acetylene 35 (the preferred moiety again being 5-phenyl-2-methyl-oxazol-4-yl-methylacetylene) is halogenated under standard conditions (ref: Boden, C. D. J. et al., J. Chem. Soc. Perkin Trans. I, 1996, 2417; or Lu, W. et. al., Tetrahedron Lett. 1998, 39, 9521) to give the corresponding halo-acetylene, which is then converted to the corresponding trans-alkenyl stannane 37 (ref: Boden, C. D. J., J. Chem. Soc., Perkin Trans. I, 1996, 2417). This aryl- or heteroaryl-substituted trans-alkenyl stannane 37 is then coupled with the halo-aryl carbamate ester 34 under standard Stille coupling conditions (ref: Farina, V. et. al., "The Stille Reaction", Organic Reactions, 1997, 50, 1) to furnish the corresponding trans-alkenyl aryl carbamate ester 38. This carbamate-ester is then deprotected under standard conditions to give the desired trans-alkenyl aryl carbamate acid analogs IZe.

The corresponding cyclopropyl analogs IZf and IZg are synthesized according to Scheme 30. For the cis- or (Z-) cyclopropyl analogs, stereoselective reduction (H.sub.2/Lindlar's catalyst) of the alkynyl moiety of intermediate alknyl ester 36 (as for analogs IZd), followed by cyclopropanation under standard conditions (Zhao, Y., et al, J. Org. Chem. 1995, 60, 5236-5242) and finally deprotection provides the cis-cyclopropyl carbamate-acid analogs IZf. For the trans-cyclopropyl analogs IF, analogous cyclopropanation of the E-alkene moiety of intermediate 38 followed by deprotection provides the trans-cyclopropyl carbamate-acid analogs IZg.

A preferred alternative asymmetric synthesis of ITa (Scheme 21) is shown in Scheme 31. Protection of a chiral amine 39 (with the phenol protected), preferably as a carbamate, provides intermediate 40. Removal of the phenolic protecting group of 40 provides the free phenol 41. Alkylation of phenol 41 with the mesylate VIII furnishes the protected amine 42. Deprotection of this amine then furnishes the key intermediate secondary amino-ester 9, which is then carried on to analogs ITa and IUa according to Scheme 21.

A preferred asymmetric synthesis of analogs IIA is shown in Scheme 32. The aldehyde IV is subjected to standard Wittig reaction conditions (ref: Preparation of Alkenes, a Practical Approach, J. J. Williams, Ed., Chapter 2, pp 19-58) to furnish the alkene 43. Asymmetric aminohydroxylation according to known literature procedures (ref: O'Brien, P., Angew. Chem. Int. Ed., 1999, 38, 326 and Reddy, K. L., and Sharpless, K. B., J. Am. Chem. Soc., 1998, 120, 1207) furnishes the desired amino-alcohol 44 as a single enantiomer. Selective protection of the amine provides the alcohol 45. Alcohol 45 is then converted to the intermediate 46, which contains a suitable leaving group (either a halide or a mesylate) for the subsequent cuprate reaction. Reaction of an appropriate higher-order cuprate (ref: L. A. Paquette, Ed., Organic Reactions, 1992, Vol. 41, J. Wiley & Sons) with the protected amine substrate 46 provides the coupled protected amine 47. Deprotection of the amine functionality of 47, followed by reaction with an ester XVIA (LG=halogen or mesylate), furnishes the corresponding secondary amino-ester 48. Acylation of 48 with an aryl or heteroaryl chloroformate XXXV provides the corresponding carbamate-ester, which is then deprotected to furnish the carbamate-acid analogs IIA. ##STR00035##

In this and the following Reaction Schemes: ##STR00036##

Alternative Scheme 1A for Preparing Aldehyde IV ##STR00037## ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049## ##STR00050## ##STR00051## ##STR00052## ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069##

Unless otherwise indicated, the term "lower alkyl", "alkyl" or "alk" as employed herein alone or as part of another group includes both straight and branched chain hydrocarbons, containing 1 to 20 carbons, preferably 1 to 10 carbons, more preferably 1 to 8 carbons, in the normal chain, and may optionally include an oxygen or nitrogen in the normal chain, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, isobutyl, pentyl, hexyl, isohexyl, heptyl, 4,4-dimethylpentyl, octyl, 2,2,4-trimethylpentyl, nonyl, decyl, undecyl, dodecyl, the various branched chain isomers thereof, and the like as well as such groups including 1 to 4 substituents such as halo, for example F, Br, Cl or I or CF.sub.3, alkoxy, aryl, aryloxy, aryl(aryl) or diaryl, arylalkyl, arylalkyloxy, alkenyl, cycloalkyl, cycloalkylalkyl, cycloalkylalkyloxy, amino, hydroxy, hydroxyalkyl, acyl, heteroaryl, heteroaryloxy, cycloheteroalkyl, arylheteroaryl, arylalkoxycarbonyl, heteroarylalkyl, heteroarylalkoxy, aryloxyalkyl, aryloxyaryl, alkylamido, alkanoylamino, arylcarbonylamino, nitro, cyano, thiol, haloalkyl, trihaloalkyl and/or alkylthio and/or any of the R.sup.3 groups.

Unless otherwise indicated, the term "cycloalkyl" as employed herein alone or as part of another group includes saturated or partially unsaturated (containing 1 or 2 double bonds) cyclic hydrocarbon groups containing 1 to 3 rings, including monocyclicalkyl, bicyclicalkyl and tricyclicalkyl, containing a total of 3 to 20 carbons forming the rings, preferably 3 to 10 carbons, forming the ring and which may be fused to 1 or 2 aromatic rings as described for aryl, which include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl and cyclododecyl, cyclohexenyl, ##STR00070## any of which groups may be optionally substituted with 1 to 4 substituents such as halogen, alkyl, alkoxy, hydroxy, aryl, aryloxy, arylalkyl, cycloalkyl, alkylamido, alkanoylamino, oxo, acyl, arylcarbonylamino, amino, nitro, cyano, thiol and/or alkylthio and/or any of the substituents for alkyl.

The term "cycloalkenyl" as employed herein alone or as part of another group refers to cyclic hydrocarbons containing 3 to 12 carbons, preferably 5 to 10 carbons and 1 or 2 double bonds. Exemplary cycloalkenyl groups include cyclopentenyl, cyclohexenyl, cycloheptenyl, cyclooctenyl, cyclohexadienyl, and cycloheptadienyl, which may be optionally substituted as defined for cycloalkyl.

The term "cycloalkylene" as employed herein refers to a "cycloalkyl" group which includes free bonds and thus is a linking group such as ##STR00071## and the like, and may optionally be substituted as defined above for "cycloalkyl".

The term "alkanoyl", as used herein alone or as part of another group refers to alkyl linked to a carbonyl group.

Unless otherwise indicated, the term "lower alkenyl" or "alkenyl" as used herein by itself or as part of another group refers to straight or branched chain radicals of 2 to 20 carbons, preferably 2 to 12 carbons, and more preferably 1 to 8 carbons in the normal chain, which include one to six double bonds in the normal chain, and may optionally include an oxygen or nitrogen in the normal chain, such as vinyl, 2-propenyl, 3-butenyl, 2-butenyl, 4-pentenyl, 3-pentenyl, 2-hexenyl, 3-hexenyl, 2-heptenyl, 3-heptenyl, 4-heptenyl, 3-octenyl, 3-nonenyl, 4-decenyl, 3-undecenyl, 4-dodecenyl, 4,8,12-tetradecatrienyl, and the like, and which may be optionally substituted with 1 to 4 substituents, namely, halogen, haloalkyl, alkyl, alkoxy, alkenyl, alkynyl, aryl, arylalkyl, cycloalkyl, amino, hydroxy, heteroaryl, cycloheteroalkyl, alkanoylamino, alkylamido, arylcarbonylamino, nitro, cyano, thiol, alkylthio and/or any of the substituents for alkyl set out herein.

Unless otherwise indicated, the term "lower alkynyl" or "alkynyl" as used herein by itself or as part of another group refers to straight or branched chain radicals of 2 to 20 carbons, preferably 2 to 12 carbons and more preferably 2 to 8 carbons in the normal chain, which include one triple bond in the normal chain, and may optionally include an oxygen or nitrogen in the normal chain, such as 2-propynyl, 3-butynyl, 2-butynyl, 4-pentynyl, 3-pentynyl, 2-hexynyl, 3-hexynyl, 2-heptynyl, 3-heptynyl, 4-heptynyl, 3-octynyl, 3-nonynyl, 4-decynyl, 3-undecynyl, 4-dodecynyl and the like, and which may be optionally substituted with 1 to 4 substituents, namely, halogen, haloalkyl, alkyl, alkoxy, alkenyl, alkynyl, aryl, arylalkyl, cycloalkyl, amino, heteroaryl, cycloheteroalkyl, hydroxy, alkanoylamino, alkylamido, arylcarbonylamino, nitro, cyano, thiol, and/or alkylthio, and/or any of the substituents for alkyl set out herein.

The terms "arylalkenyl" and "arylalkynyl" as used alone or as part of another group refer to alkenyl and alkynyl groups as described above having an aryl substituent.

Where alkyl groups as defined above have single bonds for attachment to other groups at two different carbon atoms, they are termed "alkylene" groups and may optionally be substituted as defined above for "alkyl".

Where alkenyl groups as defined above and alkynyl groups as defined above, respectively, have single bonds for attachment at two different carbon atoms, they are termed "alkenylene groups" and "alkynylene groups", respectively, and may optionally be substituted as defined above for "alkenyl" and "alkynyl".

X.sup.1.sub.x, X.sup.1.sub.m and X.sup.1.sub.n which may also be referred to as (CH.sub.2).sub.x, (CH.sub.2).sub.m, and (CH.sub.2).sub.n, respectively, or (CH.sub.2).sub.y includes alkylene, allenyl, alkenylene or alkynylene groups, as defined herein, each of which may optionally include an oxygen or nitrogen in the normal chain, which may optionally include 1, 2, or 3 substituents which include alkyl, alkenyl, halogen, cyano, hydroxy, alkoxy, amino, thioalkyl, keto, C.sub.3-C.sub.6 cycloalkyl, alkylcarbonylamino or alkylcarbonyloxy; the alkyl substituent may be an alkylene moiety of 1 to 4 carbons which may be attached to one or two carbons in the (CH.sub.2).sub.x or (CH.sub.2).sub.m or (CH.sub.2).sub.n group to form a cycloalkyl group therewith.

Examples of (CH.sub.2).sub.x, (CH.sub.2).sub.m, (CH.sub.2).sub.n, (CH.sub.2).sub.y, alkylene, alkenylene and alkynylene include ##STR00072## ##STR00073##

The term "halogen" or "halo" as used herein alone or as part of another group refers to chlorine, bromine, fluorine, and iodine as well as CF.sub.3, with chlorine or fluorine being preferred.

The term "metal ion" refers to alkali metal ions such as sodium, potassium or lithium and alkaline earth metal ions such as magnesium and calcium, as well as zinc and aluminum.

Unless otherwise indicated, the term "aryl" or the group ##STR00074## where Q is C, as employed herein alone or as part of another group refers to monocyclic and bicyclic aromatic groups containing 6 to 10 carbons in the ring portion (such as phenyl or naphthyl including 1-naphthyl and 2-naphthyl) and may optionally include one to three additional rings fused to a carbocyclic ring or a heterocyclic ring (such as aryl, cycloalkyl, heteroaryl or cycloheteroalkyl rings for example ##STR00075## and may be optionally substituted through available carbon atoms with 1, 2, or 3 groups selected from hydrogen, halo, haloalkyl, alkyl, haloalkyl, alkoxy, haloalkoxy, alkenyl, trifluoromethyl, trifluoromethoxy, alkynyl, cycloalkyl-alkyl, cycloheteroalkyl, cycloheteroalkylalkyl, aryl, heteroaryl, arylalkyl, aryloxy, aryloxyalkyl, arylalkoxy, alkoxycarbonyl, arylcarbonyl, arylalkenyl, aminocarbonylaryl, arylthio, arylsulfinyl, arylazo, heteroarylalkyl, heteroarylalkenyl, heteroarylheteroaryl, heteroaryloxy, hydroxy, nitro, cyano, amino, substituted amino wherein the amino includes 1 or 2 substituents (which are alkyl, aryl or any of the other aryl compounds mentioned in the definitions), thiol, alkylthio, arylthio, heteroarylthio, arylthioalkyl, alkoxyarylthio, alkylcarbonyl, arylcarbonyl, alkylaminocarbonyl, arylaminocarbonyl, alkoxycarbonyl, aminocarbonyl, alkylcarbonyloxy, arylcarbonyloxy, alkylcarbonylamino, arylcarbonylamino, arylsulfinyl, arylsulfinylalkyl, arylsulfonylamino or arylsulfonaminocarbonyl and/or any of the substituents for alkyl set out herein.

Unless otherwise indicated, the term "lower alkoxy", "alkoxy", "aryloxy" or "aralkoxy" as employed herein alone or as part of another group includes any of the above alkyl, aralkyl or aryl groups linked to an oxygen atom.

Unless otherwise indicated, the term "substituted amino" as employed herein alone or as part of another group refers to amino substituted with one or two substituents, which may be the same or different, such as alkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, cycloheteroalkyl, cycloheteroalkylalkyl, cycloalkyl, cycloalkylalkyl, haloalkyl, hydroxyalkyl, alkoxyalkyl or thioalkyl. These substituents may be further substituted with a carboxylic acid and/or any of the substituents for alkyl as set out above. In addition, the amino substituents may be taken together with the nitrogen atom to which they are attached to form 1-pyrrolidinyl, 1-piperidinyl, 1-azepinyl, 4-morpholinyl, 4-thiamorpholinyl, 1-piperazinyl, 4-alkyl-1-piperazinyl, 4-arylalkyl-1-piperazinyl, 4-diarylalkyl-1-piperazinyl, 1-pyrrolidinyl, 1-piperidinyl, or 1-azepinyl, optionally substituted with alkyl, alkoxy, alkylthio, halo, trifluoromethyl or hydroxy.

Unless otherwise indicated, the term "lower alkylthio", alkylthio", "arylthio" or "aralkylthio" as employed herein alone or as part of another group includes any of the above alkyl, aralkyl or aryl groups linked to a sulfur atom.

Unless otherwise indicated, the term "lower alkylamino", "alkylamino", "arylamino", or "arylalkylamino" as employed herein alone or as part of another group includes any of the above alkyl, aryl or arylalkyl groups linked to a nitrogen atom.

Unless otherwise indicated, the term "acyl" as employed herein by itself or part of another group, as defined herein, refers to an organic radical linked to a carbonyl ##STR00076## group; examples of acyl groups include any of the R.sup.3 groups attached to a carbonyl, such as alkanoyl, alkenoyl, aroyl, aralkanoyl, heteroaroyl, cycloalkanoyl, cycloheteroalkanoyl and the like.

Unless otherwise indicated, the term "cycloheteroalkyl" as used herein alone or as part of another group refers to a 5-, 6- or 7-membered saturated or partially unsaturated ring which includes 1 to 2 hetero atoms such as nitrogen, oxygen and/or sulfur, linked through a carbon atom or a heteroatom, where possible, optionally via the linker (CH.sub.2).sub.p (where p is 1, 2 or 3), such as ##STR00077## and the like. The above groups may include 1 to 4 substituents such as alkyl, halo, oxo and/or any of the substituents for alkyl or aryl set out herein. In addition, any of the cycloheteroalkyl rings can be fused to a cycloalkyl, aryl, heteroaryl or cycloheteroalkyl ring.

Unless otherwise indicated, the term "heteroaryl" as used herein alone or as part of another group refers to a 5- or 6-membered aromatic ring including ##STR00078## where Q is N, which includes 1, 2, 3 or 4 hetero atoms such as nitrogen, oxygen or sulfur, and such rings fused to an aryl, cycloalkyl, heteroaryl or cycloheteroalkyl ring (e.g. benzothiophenyl, indolyl), and includes possible N-oxides. The heteroaryl group may optionally include 1 to 4 substituents such as any of the substituents for alkyl or aryl set out above. Examples of heteroaryl groups include the following: ##STR00079## and the like.

The term "cycloheteroalkylalkyl" as used herein alone or as part of another group refers to cycloheteroalkyl groups as defined above linked through a C atom or heteroatom to a (CH.sub.2).sub.p chain.

The term "heteroarylalkyl" or "heteroarylalkenyl" as used herein alone or as part of another group refers to a heteroaryl group as defined above linked through a C atom or heteroatom to a --(CH.sub.2).sub.p-- chain, alkylene or alkenylene as defined above.

The term "polyhaloalkyl" as used herein refers to an "alkyl" group as defined above which includes from 2 to 9, preferably from 2 to 5, halo substituents, such as F or Cl, preferably F, such as CF.sub.3CH.sub.2, CF.sub.3 or CF.sub.3CF.sub.2CH.sub.2.

The term "polyhaloalkyloxy" as used herein refers to an "alkoxy" or "alkyloxy" group as defined above which includes from 2 to 9, preferably from 2 to 5, halo substituents, such as F or Cl, preferably F, such as CF.sub.3CH.sub.2O, CF.sub.3O or CF.sub.3CF.sub.2CH.sub.2O.

The term "prodrug esters" as employed herein includes prodrug esters which are known in the art for carboxylic and phosphorus acid esters such as methyl, ethyl, benzyl and the like. Other prodrug ester examples of R.sup.4 include the following groups: (1-alkanoyloxy)alkyl such as, ##STR00080## wherein R.sup.a, R.sup.b and R.sup.c are H, alkyl, aryl or arylalkyl; however, R.sup.aO cannot be HO. Examples of such prodrug esters R.sup.4 include ##STR00081## Other examples of suitable prodrug esters R.sup.4 include ##STR00082## wherein R.sup.a can be H, alkyl (such as methyl or t-butyl), arylalkyl (such as benzyl) or aryl (such as phenyl); R.sup.d is H, alkyl, halogen or alkoxy, R.sup.e is alkyl, aryl, arylalkyl or alkoxyl, and n.sub.1 is 0, 1 or 2.

Where the compounds of structure I are in acid form they may form a pharmaceutically acceptable salt such as alkali metal salts such as lithium, sodium or potassium, alkaline earth metal salts such as calcium or magnesium as well as zinc or aluminum and other cations such as ammonium, choline, diethanolamine, lysine (D or L), ethylenediamine, t-butylamine, t-octylamine, tris-(hydroxymethyl)aminomethane (TRIS), N-methyl glucosamine (NMG), triethanolamine and dehydroabietylamine.

All stereoisomers of the compounds of the instant invention are contemplated, either in admixture or in pure or substantially pure form. The compounds of the present invention can have asymmetric centers at any of the carbon atoms including any one or the R substituents. Consequently, compounds of formula I can exist in enantiomeric or diastereomeric forms or in mixtures thereof. The processes for preparation can utilize racemates, enantiomers or diastereomers as starting materials. When diastereomeric or enantiomeric products are prepared, they can be separated by conventional methods for example, chromatographic or fractional crystallization.

Where desired, the compounds of structure I may be used in combination with one or more hypolipidemic agents or lipid-lowering agents and/or one or more other types of therapeutic agents including antidiabetic agents, anti-obesity agents, antihypertensive agents, platelet aggregation inhibitors, and/or anti-osteoporosis agents, which may be administered orally in the same dosage form, in a separate oral dosage form or by injection.

The hypolipidemic agent or lipid-lowering agent which may be optionally employed in combination with the compounds of formula I of the invention may include 1, 2, 3 or more MTP inhibitors, HMG CoA reductase inhibitors, squalene synthetase inhibitors, fibric acid derivatives, ACAT inhibitors, lipoxygenase inhibitors, cholesterol absorption inhibitors, ileal Na.sup.+/bile acid cotransporter inhibitors, upregulators of LDL receptor activity, bile acid sequestrants, and/or nicotinic acid and derivatives thereof.

MTP inhibitors employed herein include MTP inhibitors disclosed in U.S. Pat. No. 5,595,872, U.S. Pat. No. 5,739,135, U.S. Pat. No. 5,712,279, U.S. Pat. No. 5,760,246, U.S. Pat. No. 5,827,875, U.S. Pat. No. 5,885,983 and U.S. application Ser. No. 09/175,180 filed Oct. 20, 1998, now U.S. Pat. No. 5,962,440. Preferred are each of the preferred MTP inhibitors disclosed in each of the above patents and applications.

All of the above U.S. Patents and applications are incorporated herein by reference.

Most preferred MTP inhibitors to be employed in accordance with the present invention include preferred MTP inhibitors as set out in U.S. Pat. Nos. 5,739,135 and 5,712,279, and U.S. Pat. No. 5,760,246.

The most preferred MTP inhibitor is 9-[4-[4-[[2-(2,2,2-Trifluoroethoxy)benzoyl]amino]-1-piperidinyl]butyl]-N-- (2,2,2-trifluoroethyl)-9H-fluorene-9-carboxamide ##STR00083##

The hypolipidemic agent may be an HMG CoA reductase inhibitor which includes, but is not limited to, mevastatin and related compounds as disclosed in U.S. Pat. No. 3,983,140, lovastatin (mevinolin) and related compounds as disclosed in U.S. Pat. No. 4,231,938, pravastatin and related compounds such as disclosed in U.S. Pat. No. 4,346,227, simvastatin and related compounds as disclosed in U.S. Pat. Nos. 4,448,784 and 4,450,171. Other HMG CoA reductase inhibitors which may be employed herein include, but are not limited to, fluvastatin, disclosed in U.S. Pat. No. 5,354,772, cerivastatin disclosed in U.S. Pat. Nos. 5,006,530 and 5,177,080, atorvastatin disclosed in U.S. Pat. Nos. 4,681,893, 5,273,995, 5,385,929 and 5,686,104, itavastatin (Nissan/Sankyo's nisvastatin (NK-104)) disclosed in U.S. Pat. No. 5,011,930, Shionogi-Astra/Zeneca visastatin (ZD-4522) disclosed in U.S. Pat. No. 5,260,440, and related statin compounds disclosed in U.S. Pat. No. 5,753,675, pyrazole analogs of mevalonolactone derivatives as disclosed in U.S. Pat. No. 4,613,610, indene analogs of mevalonolactone derivatives as disclosed in PCT application WO 86/03488, 6-[2-(substituted-pyrrol-1-yl)-alkyl)pyran-2-ones and derivatives thereof as disclosed in U.S. Pat. No. 4,647,576, Searle's SC-45355 (a 3-substituted pentanedioic acid derivative) dichloroacetate, imidazole analogs of mevalonolactone as disclosed in PCT application WO 86/07054, 3-carboxy-2-hydroxy-propane-phosphonic acid derivatives as disclosed in French Patent No. 2,596,393, 2,3-disubstituted pyrrole, furan and thiophene derivatives as disclosed in European Patent Application No. 0221025, naphthyl analogs of mevalonolactone as disclosed in U.S. Pat. No. 4,686,237, octahydronaphthalenes such as disclosed in U.S. Pat. No. 4,499,289, keto analogs of mevinolin (lovastatin) as disclosed in European Patent Application No.0,142,146 A2, and quinoline and pyridine derivatives disclosed in U.S. Pat. Nos. 5,506,219 and 5,691,322.

In addition, phosphinic acid compounds useful in inhibiting HMG CoA reductase suitable for use herein are disclosed in GB 2205837.

The squalene synthetase inhibitors suitable for use herein include, but are not limited to, .alpha.-phosphono-sulfonates disclosed in U.S. Pat. No. 5,712,396, those disclosed by Biller et al, J. Med. Chem., 1988, Vol. 31, No. 10, pp 1869-1871, including isoprenoid (phosphinyl-methyl)phosphonates as well as other known squalene synthetase inhibitors, for example, as disclosed in U.S. Pat. Nos. 4,871,721 and 4,924,024 and in Biller, S. A., Neuenschwander, K., Ponpipom, M. M., and Poulter, C. D., Current Pharmaceutical Design, 2, 1-40 (1996).

In addition, other squalene synthetase inhibitors suitable for use herein include the terpenoid pyrophosphates disclosed by P. Ortiz de Montellano et al, J. Med. Chem., 1977, 20, 243-249, the farnesyl diphosphate analog A and presqualene pyrophosphate (PSQ-PP) analogs as disclose