SUBSTITUTED PYRIDO(3,2-D) PYRIMIDINES AND PHARMACEUTICAL COMPOSITIONS FOR TREATING VIRAL INFECTIONS

• US 20090253696A1
• Filed: 06/20/2007
• Published: 10/08/2009
• Est. Priority Date: 07/20/2006
• Status: Active Grant

• Current Assignee: Gilead Sciences Inc.
• Original Assignee: Gilead Sciences Inc.
• Inventors: Herdewijn, Piet Andre' Maurits Maria, Zhang, Jennifer, De Jonghe, Steven Cesar Alfons, Watkins, William John, Chong, Lee Shun
• Granted Patent: US 8,338,435 B2
• Time in Patent Office: Days
• US Class Current: 514/234.200
• CPC Class Codes: A61P 31/12 Antivirals
• CPC Class Codes: C07D 471/04 Ortho-condensed systems

Abstract

This invention provides di-, tri- and tetra-substituted pyrido(3,2-d)pyrimidine derivatives with specific substituting patterns, their pharmaceutically acceptable salts, N-oxides, solvates, pro-drugs and enantiomers, possessing unexpectedly desirable pharmaceutical properties, in particular being highly active antiviral agents. The invention also provides use of such derivatives in the treatment of viral infections and pathologic conditions associated therewith, including hepatitis C.

Claims

1-30. -30. (canceled)

31. A pyrido(3,2-d)pyrimidine derivative represented by the structural formula:

wherein;

R₁ is selected from the group consisting of hydrogen;

halogen;

cyano;

carboxylic acid;

acyl;

thioacyl;

C_1-7 alkoxycarbonyl;

acyloxy;

carbonate;

carbamate;

C_1-7 alkyl;

aryl;

amino;

acylamino;

thioacylamino;

N-protected amino;

(mono- or di-) C_1-7 alkylamino;

(mono- or di-) arylamino;

(mono- or di-) C_3-10 cycloalkylamino;

(mono- or di-) hydroxy C_1-7 alkylamino;

(mono- or di-) C_1-7 alkyl-arylamino;

mercapto C_1-7 alkyl;

C_1-7 alkyloxy; and

groups having the structural formula R₆—

NR₇R₁₂, wherein R₆ is a bond or C_1-7 alkylene, and wherein R₇ and R₁₂ are independently selected from the group consisting of hydrogen, C_1-7 alkyl, C_2-7 alkenyl, C_2-7 alkynyl, aryl C_1-7alkyl, C_3-10 cycloalkyl, aryl and heteroaryl, wherein said aryl or heteroaryl is optionally substituted with one or more substituents independently selected from the group consisting of halogen and C_1-7 alkyl, and wherein said C_3-10 cycloalkyl is optionally substituted at the carbon position adjacent to the nitrogen atom to which it is attached, with aryl or heteroaryl wherein said aryl or heteroaryl is optionally substituted with halogen, or wherein R₇ and R₁₂ together with the nitrogen to which they are attached form a heterocyclic group; and

groups having the structural formula —

NH—

CHR₈R₈′

wherein R₈ is selected from the group consisting of C_1-7 alkyl substituted with one or more substituents independently selected from the group consisting of halogen and C_1-7 alkoxy, C_3-10 cycloalkyl, aryl substituted with one or more R₁₄, and heterocyclyl, and wherein R₈′

is selected from the group consisting of hydrogen, C_1-7 alkyl optionally substituted with one or more substituents independently selected from the group consisting of halogen and C_1-7 alkoxy, C_3-10 cycloalkyl, aryl optionally substituted with one or more R₁₄, and heterocyclyl;

R₂ is selected from the group consisting of C_1-14 alkyl, C_2-7 alkenyl, C_2-7 alkynyl, halo C_1-7 alkyl, hydroxy C_1-7 alkyl, C_1-7alkoxy-C_1-7alkyl, arylalkenyl, C_3-10 cycloalkyl, heterocyclyl C_1-7 alkyl, C_3-10 cycloalkyl-C_1-7 alkyl, aryl and aryl-C_1-7alkyl, wherein the aryl moiety of said aryl or aryl-C_1-7alkyl is optionally substituted with one or more substituents independently selected from the group consisting of halogen, C_1-7alkoxy and C_1-7alky;

R₄ is hydrogen and R₃ is selected from the group consisting of halogen, heterocyclyl (in particular heteroaryl) and aryl groups, wherein said heterocyclyl (in particular heteroaryl) or aryl groups are optionally substituted with one or more substituents independently selected from the group consisting of halogen, C_1-7 alkyl, C_2-7 alkenyl, C_2-7 alkynyl, halo C_1-7 alkyl, C_3-10 cycloalkyl, aryl, nitro, hydroxyl, sulfhydryl, amino, C_1-7 alkoxy, C_3-10 cycloalkoxy, aryloxy, arylalkyloxy, oxyheterocyclic, heterocyclic-substituted alkyloxy, thio C_1-7 alkyl, thio C_3-10 cycloalkyl, thioaryl, thio-heterocyclyl, arylalkylthio, heterocyclyl-C_1-7 alkylthio, formyl, —

CO—

NHR₉, —

CO—

NR₉R₉′

, —

CS—

NHR₉, —

NR₁₃—

CO—

NHR₁₃, —

NR₁₃—

CS—

NHR₁₃, —

SO₂NH₂, —

NR₁₃—

SO₂R₁₁, —

NR₁₃—

COR₁₀, —

NR₁₃—

CSR₁₀, hydroxylamino, C_1-7 alkoxyamino, mercaptoamino, thioalkylamino, cyano, carboxylic acid or esters or thioesters or halides or anhydrides or amides thereof, thiocarboxylic acid or esters or thioesters or halides or anhydrides or amides thereof, C_1-7 alkylamino, C_3-10 cycloalkylamino, C_2-7 alkenylamino, C_3-10cycloalkenylamino, C_2-7alkynylamino, arylamino, arylC_1-7alkylamino, hydroxy C_1-7alkylamino, mercapto C_1-7alkylamino, heterocyclylamino, C_1-7alkylsulfoxide, C_1-7alkylsulfone, hydrazino, C_1-7 alkylhydrazino, phenylhydrazino, and heterocyclyl optionally substituted with one or more substituents independently selected from the group consisting of hydroxy, oxo, halogen, amino, C_1-7 alkyl and C_1-7alkoxy;

or R₃ and R₄ are independently selected from hydrogen;

aryl being substituted with one or more substituents independently selected from the group consisting of aryl wherein said aryl is optionally substituted with arylcarbonyl;

(O,O-dialkylphosphonyl)-alkyl;

acyl, halo-C_1-7 alkoxy, hydroxy-C_1-7 alkoxy, hydroxy-C_1-7 alkyl, di-(C_1-7alkyl)amino C_1-7alkyl, ω

-carboxy-acylamino, mono-C_3-7 cycloalkyl-aminocarbonyl, di-(C_3-7cycloalkyl)aminocarbonyl, mono-(C_1-7 alkyl)aminocarbonyl, mono-(ω

-dimethylamino-C_1-7alkyl)aminocarbonyl, (di-C_1-7alkyl)aminocarbonyl, mono-(hydroxy-C_1-7alkyl)aminocarbonyl, formylamino, SO₂NH₂, arylamino-C_1-7alkyl, C_1-7alkylsulfonyl, heterocyclyl-carbonyl, heterocyclyl-C_1-7alkyl and hetero-cyclyl, wherein said heterocyclyl is optionally substituted with C_3-7 alkenyloxycarbonyl, C_1-7alkyl or C_1-7alkyloxycarbonyl;

a fused benzo-C_5-8 cycloalkyl optionally substituted with oxo;

or a heterocyclyl substituted with one or more substituents independently selected from the group consisting of acylamino, C_1-7 alkylsulfonyl, arylsulfonyl, heterocyclyl-C_1-7 alkyl, heterocyclyl-C_1-7alkylamino, aryl and heterocyclyl, wherein said heterocyclyl is optionally substituted with C_1-7 alkyl, arylsulfonyl or (di-C_1-7 alkylamino)-C_1-7 alkoxy, or said heterocyclyl is non-aromatic and includes a nitrogen atom substituted with heterocyclyl-C_1-7 alkyl or a carboxylic acid or a C_1-7 alkyl ester thereof;

provided that R₃ and R₄ are not both hydrogen;

R₉ and R₉′

are each independently selected from the group consisting of hydrogen, C_3-10 cycloalkyl optionally substituted with one more substituents independently selected from the group consisting of cyano, halogen, hydroxy, amino, C_1-7 alkyl and C_1-7 alkoxy;

C_1-7 alkoxy;

C_1-7 alkyl optionally substituted with one or more substituents independently selected from the group consisting of amino C_1-7 alkylamino, cyano, di-C_1-7 alkylamino, halogen, and heterocyclyl optionally substituted with C_1-7alkyl;

aryl and arylC_1-7alkyl wherein the aryl moiety is optionally substituted with one or more halogens;

or R₉ and R₉′

together with the nitrogen atom to which they are attached form a heterocyclyl group;

each R₁₀ and each R₁₁ is independently selected from the group consisting of C_1-7 alkyl optionally substituted with one or more substituents independently selected from the group consisting of amino, cyano, halogen and hydroxy;

C_1-7 alkoxy optionally substituted with one or more substituents independently selected from the group consisting of amino, C_1-7alkylamino, cyano, di-C_1-7alkylamino, halogen, and heterocyclyl optionally substituted with one or more substituents independently selected from the group consisting of C_1-7 alkyl, acylamino and oxo;

C_3-10 cycloalkyl optionally substituted with one or more substituents independently selected from the group consisting of amino and hydroxy; and

amino optionally substituted with one or more substituents independently selected from the group consisting of C_1-7 alkyl wherein said C_1-7 alkyl is optionally substituted with one or more substituents independently selected from the group consisting of amino, C_1-7 alkylamino, cyano, di-C_1-7 alkylamino, halogen and heterocyclyl;

each R₁₃ is hydrogen or C_1-7 alkyl, optionally substituted with one or more substituents independently selected from the group consisting of cyano, halogen and hydroxy;

each R₁₄ is independently selected from the group consisting of halogen, hydroxy, amino, nitro, cyano, halo C_1-7 alkyl, halo C_1-7 alkoxy, C_1-7 alkyl, C_1-7 alkoxy, di-C_1-7 alkylamino, mono-C_1-7 alkylamino, carboxamido, —

SO₂NH₂, carbamoyl, —

NR₁₃—

SO₂R₁₁ and phenoxy,

or a pharmaceutical acceptable addition salt or a stereochemical isomeric form thereof or a N-oxide thereof or a solvate thereof or a pro-drug form thereof, provided said pyrido(3,2-d)pyrimidine derivative is not 2-amino-4-n-propyl-6-(4-fluorophenyl)-pyrido(3,2-d)pyrimidine.

32. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₄ is hydrogen.

33. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₁ is not hydrogen.

34. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₁ is amino or acetamido.

35. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₃ is a phenyl group substituted with one substituent.

36. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₂ is selected from the group consisting of methyl, ethyl, n-propyl, isopropyl and but-3-enyl.

37. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₃ is a phenyl group substituted with a substituent selected from the group consisting of fluoro and acetamido.

38. A pyrido(3,2-d)pyrimidine derivative according to claim 31, wherein R₃ is a phenyl group substituted with one substituent in para position on said phenyl group.

39. A pyrido(3,2-d)pyrimidine derivative according to claim 31, being 2-amino-4-n-propyl-6-(4-fluorophenyl)-pyrido(3,2-d)pyrimidine.

40. A pyrido(3,2-d)pyrimidine derivative according to claim 31, being selected from the group consisting of:

1-[4-(2-amino-4-cyclopropyl-pyrido[3,2-d]pyrimidin-6-yl)-phenyl]-pyrrolidin-2-one,

4-cyclopropyl-6-(4-fluoro-phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluoro-phenyl)-4-isopropyl-pyrido[3,2-d]pyrimidin-2-ylamine,

4-methyl-6-(4-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-(2-[1,3]Dioxan-2-yl-ethyl)-6-(4-fluoro-phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(5-amino-pyrazin-2-yl)-4-ethyl-pyrido[3,2-d]pyrimidin-2-ylamine,

1-[4-(2-amino-4-ethyl-pyrido[3,2-d]pyrimidin-6-yl)-phenyl]-pyrrolidin-2-one,

4-but-3-enyl-6-(4-fluoro-phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluoro-phenyl)-4-isobutyl-pyrido[3,2-d]pyrimidin-2-ylamine,

4-ethyl-6-(4-fluoro-phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluoro-phenyl)-4-n-propyl-pyrido[3,2-d]pyrimidine,

N-[4-(2-amino-4-n-propyl-pyrido[3,2-d]pyrimidin-6-yl)-phenyl]-acetamide,

6-(4-fluorophenyl)-4-propyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-methyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-ethyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-isopropyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-isobutyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-pentyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-tert-butyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-hexyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-heptyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-octyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-decyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-allyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-ethynyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-phenyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-methoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-chlorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-fluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-methylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-methylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-methylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-vinyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-cyclohexyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-cyclopentyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-cyclopropyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-but-3-enyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(pyrid-2-yl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(1,3-dioxan-2-ylmethyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-benzyl-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(thien-3-yl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(naphth-1-yl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(naphth-2-yl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-methylbenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-methylbenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-methylbenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-methoxybenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-methoxybenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-methoxybenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-chlorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-chlorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-chlorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-fluorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-fluorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-fluorobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-bromobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-bromobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-bromobenzyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2-biphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-biphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-fluoro-4-biphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,4-dichlorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,5-dichlorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,4-difluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,5-difluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-chloro-4-fluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3-chloro-5-fluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-chloro-3-fluorophenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,5-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,4-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,3-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,4-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,5-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,6-dimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(3,4,5-trimethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,4,5-trimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(2,4,6-trimethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-ethylphenyl)-pyrido[3,2-d]pyrimidine,

6-(4-fluorophenyl)-4-(4-ethoxyphenyl)-pyrido[3,2-d]pyrimidine,

6-chloro-4-methyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-ethyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-isopropyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-isobutyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-pentyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-tert-butyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-hexyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-heptyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-octyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-decyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-allyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-ethynyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-phenyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-methoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-chlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-vinyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-cyclohexyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-cyclopentyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-cyclopropyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-but-3-enyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(pyrid-2-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(1,3-dioxan-2-ylmethyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-benzyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(thien-3-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(naphth-1-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(naphth-2-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-fluoro-4-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,4-dichlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,5-dichlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,4-difluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,5-difluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-chloro-4-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3-chloro-5-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-chloro-3-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,5-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,4-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,3-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,4-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,5-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,6-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(3,4,5-trimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,4,5-trimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(2,4,6-trimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-ethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-chloro-4-(4-ethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-methyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-ethyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-isopropyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-isobutyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-pentyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-tert-butyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-hexyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-heptyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-octyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-decyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-allyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-ethynyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-phenyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-methoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-chlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-methylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-vinyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-cyclohexyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-cyclopentyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-cyclopropyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-but-3-enyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(pyrid-2-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(1,3-dioxan-2-ylmethyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-benzyl-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(thien-3-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(naphth-1-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(naphth-2-yl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-methylbenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-methoxybenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-chlorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-fluorobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-bromobenzyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-fluoro-4-biphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,4-dichlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,5-dichlorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,4-difluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,5-difluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-chloro-4-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3-chloro-5-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-chloro-3-fluorophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,5-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,4-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,3-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,4-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,5-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,6-dimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,4-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,5-dimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(3,4,5-trimethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,4,5-trimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(2,4,6-trimethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-ethylphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

6-(4-fluorophenyl)-4-(4-ethoxyphenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(4′

-allyloxycarbonylpiperazino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-amino-5-chlorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-amino-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-amino-4-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-amino-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-amino-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-benzyloxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-benzyloxy-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-biphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-n-butyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-isobutylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-carboxy-3-fluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-chloro-4-hydroxy-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloro-5-hydroxymethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(N-cyclopropylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(N,N-diethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(N,N-dimethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-[1,3]dioxolan-2-ylmethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(3-ethoxycarbonylpiperidino)carboxamidophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-formyl-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-formyl-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-formyl-2-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-formyl-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-hydroxy-3,5-dimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(2-hydroxyethyl)-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(2-hydroxyethyl)aminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-hydroxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-hydroxy-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-hydroxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-isopropoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(4-isopropylpiperazinyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-isopropylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methanesulfonamido phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-methoxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methoxy-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-methoxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-N-methylcarboxamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(N-methylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(morpholinocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-morpholinophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(morpholinomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-phenoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(N-phenylaminomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(phenylcarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(piperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-piperazinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(sulfamoylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(tert-butoxycarbonylamino)-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,3,4-trifluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-tert-butylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(tetrahydro-2H-pyran-2-yloxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(2-thienyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,4,6-trimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3,4,5-trimethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-vinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-(2-hydroxyethoxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(6-benzyloxynaphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(naphth-1-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(naphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4′

-benzoyl[1,1′

-biphenyl]-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-biphenylyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(oxoindan-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(benzodioxolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-acetamidopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-aminopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-aminopyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1,4-benzodioxan-6-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-benzothien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-benzyloxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-benzyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-bromo-3-chloropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-bromo-2,3-dihydrobenzo[b]furan-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-bromo-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-bromothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloro-6-isopropylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-[4-(4-chlorophenylsulfonyl)piperazin-1-yl]pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloropyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloropyrid-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(dibenzo[b,d]furan-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-chloro-3-fluoropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(dibenzo[b,d]thien-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3,4-dihydro-2H-1,5-benzodioxepin-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3,6-dihydro-2H-pyridine-1-tert-butoxycarbonyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,5-dibromopyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,6-dichloropyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,3-dihydro-1-benzofuran-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,6-dimethoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,6-dimethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,4-dimethoxypyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3,5-dimethylisoxazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(3-N,N-dimethylaminopropoxy)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3,5-dimethylpyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-[1,3]dioxolan-2-ylmethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,4-dioxo-1,2,3,4-tetrahydro-5-pyrido[3,2-d]pyrimidinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2,4-di(tert-butoxy)pyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-ethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-fluoro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-fluoropyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-formyl-2-furyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-formylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(furan-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-hydroxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-isobutyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(isoquinolin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methoxypyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methyl-1-benzothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-(3-methylbutyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methylfuran-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-methylindol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methyl-3-phenyl-4-isoxazolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-(methylthio)thien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(4-methylpiperazinyl)pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(4-methylpiperazinyl)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-methyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(3-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-methoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(2-morpholinoethylamino)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(2-morpholinoethyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(morpholin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-(phenylsulfonyl)-1H-indol-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(5-phenyl-2-thienyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(piperazin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(piperazin-1-yl)-pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-propyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(4-phenoxathiinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(quinolin-8-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(quinolin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(2-(4-tert-butoxycarbonylpiperazinyl)-pyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-tert-butoxycarbonyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-tert-butoxycarbonyl-2-pyrrolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-(tert-butoxycarbonyl)-5-bromo-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-(tert-butoxycarbonyl)-1H-indol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-(tert-butoxycarbonyl)-5-methoxy-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1-thianthrenylthien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-n-propyl-6-(1,3,5-trimethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(4′

-allyloxycarbonylpiperazino)phenyl)pyrimidin-2-ylamine,

4-phenyl-6-(3-aminocarbonylphenyl)pyrimidin-2-ylamine,

4-phenyl-6-(4-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-amino-5-chlorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-amino-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-amino-4-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-amino-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-amino-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-benzyloxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-benzyloxy-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-biphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-n-butyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-isobutylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-carboxy-3-fluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-chloro-4-hydroxy-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloro-5-hydroxymethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(N-cyclopropylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(N,N-diethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(N,N-dimethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-[1,3]dioxolan-2-ylmethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(3-ethoxycarbonylpiperidino)carboxamidophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-formyl-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-formyl-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-formyl-2-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-formyl-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-hydroxy-3,5-dimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(2-hydroxyethyl)-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(2-hydroxyethyl)aminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-hydroxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-hydroxy-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-hydroxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-isopropoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(4-isopropylpiperazinyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-isopropylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methanesulfonamido phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-methoxycarbonyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-methoxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methoxy-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-methoxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-N-methylcarboxamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(N-methylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(morpholinocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-morpholinophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(morpholinomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-phenoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(N-phenylaminomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(phenylcarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(piperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-piperazinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(sulfamoylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(tert-butoxycarbonylamino)-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,3,4-trifluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-tert-butylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(tetrahydro-2H-pyran-2-yloxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(2-thienyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,4,6-trimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3,4,5-trimethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-vinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-(2-hydroxyethoxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(6-benzyloxynaphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(naphth-1-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(naphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4′

-benzoyl[1′

,1′

-biphenyl]-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-biphenylyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(oxoindan-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(benzodioxolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-acetamidopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-aminopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-aminopyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1,4-benzodioxan-6-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-benzothien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-benzyloxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-benzyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-bromo-3-chloropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-bromo-2,3-dihydrobenzo[b]furan-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-bromo-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-bromothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloro-6-isopropylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-[4-(4-chlorophenylsulfonyl)piperazin-1-yl]pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloropyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloropyrid-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(dibenzo[b,d]furan-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-chloro-3-fluoropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(dibenzo[b,d]thien-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3,4-dihydro-2H-1,5-benzodioxepin-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3,6-dihydro-2H-pyridine-1-tert-butoxycarbonyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,5-dibromopyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,6-dichloropyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,3-dihydro-1-benzofuran-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,6-dimethoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,6-dimethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,4-dimethoxypyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3,5-dimethylisoxazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(3-N,N-dimethylaminopropoxy)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3,5-dimethylpyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-[1,3]dioxolan-2-ylmethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,4-dioxo-1,2,3,4-tetrahydro-5-pyrimidinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2,4-di(tert-butoxy)pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-ethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-fluoro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-fluoropyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-formyl-2-furyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-formylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(furan-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-hydroxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-isobutyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(isoquinolin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methoxypyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methyl-1-benzothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-(3-methylbutyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methylfuran-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-methylindol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methyl-3-phenyl-4-isoxazolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-(methylthio)thien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(4-methylpiperazinyl)pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(4-methylpiperazinyl)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-methyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(3-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-methoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(2-morpholinoethylamino)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(2-morpholinoethyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(morpholin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-(phenylsulfonyl)-1H-indol-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(5-phenyl-2-thienyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(piperazin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(piperazin-1-yl)-pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-propyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(4-phenoxathiinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(quinolin-8-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(quinolin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(2-(4-tert-butoxycarbonylpiperazinyl)-pyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-tert-butoxycarbonyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-tert-butoxycarbonyl-2-pyrrolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-(tert-butoxycarbonyl)-5-bromo-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-(tert-butoxycarbonyl)-1H-indol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-(tert-butoxycarbonyl)-5-methoxy-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1-thianthrenylthien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-phenyl-6-(1,3,5-trimethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(4′

-allyloxycarbonylpiperazino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-amino-5-chlorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-amino-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-amino-4-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-amino-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-amino-2-methyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-amino-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-benzyloxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-benzyloxy-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-biphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-n-butyl phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-isobutylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-carboxy-3-fluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(3-carboxypropionylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-chloro-4-hydroxy-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloro-5-hydroxymethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-cyanomethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-cyanophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(N-cyclopropylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(N,N-diethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(N,N-dimethylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(N,N-dimethylaminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-[(N′

,N′

-dimethylamino)ethylaminocarbonyl]phenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-[1,3]dioxolan-2-ylmethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(ethoxycarbonyl)methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-ethoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(3-ethoxycarbonyl piperidino)carboxamidophenyl)-pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-formylaminophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-formyl-5-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-formyl-4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-formyl-2-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-formyl-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-formylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-hydroxy-3,5-dimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(2-hydroxyethyl)-aminocarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(2-hydroxyethyl)aminocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-hydroxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-hydroxy-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(hydroxymethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-hydroxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-isopropoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(4-isopropylpiperazinyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-isopropylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-methanesulfonamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methanesulfonamido phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-methoxy-4-methoxycarbonylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methoxy-5-methylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-methoxy-3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-N-methylcarboxamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(N-methylamino)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(4-methylpiperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(methylthio)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(morpholinocarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-morpholinophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(morpholinomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-nitrophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-phenoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(N-phenylaminomethyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(phenylcarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(piperazine-1-carbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-piperazinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-succinamidophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(sulfamoylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(toluene-4-sulfonamido)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(tert-butoxycarbonylamino)-3-methoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(tert-butoxycarbonyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,3,4-trifluorophenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-tert-butylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(tetrahydro-2H-pyran-2-yloxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(2-thienyl)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,4,6-trimethylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3,4,5-trimethoxyphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-vinylphenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-(2-hydroxyethoxy)phenyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(6-benzyloxynaphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(naphth-1-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(naphth-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4′

-benzoyl[1,1′

-biphenyl]-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-biphenylyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(oxoindan-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(benzodioxolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-acetamidopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-aminopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-aminopyrido[3,2-d]pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1,4-benzodioxan-6-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-benzothien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-benzyloxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-benzyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-bromo-3-chloropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-bromo-2,3-dihydrobenzo[b]furan-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-bromo-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-bromopyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-bromothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloro-6-isopropylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-[4-(4-chlorophenylsulfonyl)piperazin-1-yl]pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloropyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloropyrid-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(dibenzo[b,d]furan-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-chloro-3-fluoropyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(dibenzo[b,d]thien-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3,4-dihydro-2H-1,5-benzodioxepin-7-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3,6-dihydro-2H-pyridine-1-tert-butoxycarbonyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,5-dibromopyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,6-dichloropyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,3-dihydro-1-benzofuran-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,6-dimethoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,6-dimethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,4-dimethoxypyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3,5-dimethylisoxazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(3-N,N-dimethylaminopropoxy)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3,5-dimethylpyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-[1,3]dioxolan-2-ylmethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,4-dioxo-1,2,3,4-tetrahydro-5-pyrimidinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2,4-di(tert-butoxy)pyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-ethoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-fluoro-3-methylpyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-fluoropyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-formyl-2-furyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-formylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(furan-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-hydroxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-isobutyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(isoquinolin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methoxypyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methoxypyrimidin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methyl-1-benzothien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-(3-methyl butyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methylfuran-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-methylindol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methyl-3-phenyl-4-isoxazolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-(methylthio)thien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(4-methylpiperazinyl)pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(4-methylpiperazinyl)pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-methyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(3-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methylpyridin-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methylpyridin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-methoxypyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-methylthien-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(2-morpholinoethylamino)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(2-morpholinoethyl)-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(morpholin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-(phenylsulfonyl)-1H-indol-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(5-phenyl-2-thienyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(piperazin-1-yl)-pyridin-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(piperazin-1-yl)-pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-propyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(pyridin-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(4-phenoxathiinyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(quinolin-8-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(quinolin-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(2-(4-tert-butoxycarbonylpiperazinyl)-pyrid-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-tert-butoxycarbonyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-tert-butoxycarbonyl-2-pyrrolyl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-(tert-butoxycarbonyl)-5-bromo-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-(tert-butoxycarbonyl)-1H-indol-5-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-(tert-butoxycarbonyl)-5-methoxy-1H-indol-2-yl)pyrido[3,2-d]pyrimidin-2-ylamine,

4-benzyl-6-(1-thianthrenylthien-3-yl)pyrido[3,2-d]pyrimidin-2-ylamine, and

4-benzyl-6-(1,3,5-trimethyl-1H-pyrazol-4-yl)pyrido[3,2-d]pyrimidin-2-ylamine.

41. A pharmaceutical composition comprising one or more pharmaceutically acceptable carriers and a pyrido(3,2-d)pyrimidine derivative according to claim 31.

42. A pharmaceutical composition according to claim 41, further comprising one or more antiviral agents.

43. A method of prevention or treatment of a viral infection, comprising the administration to a patient in need thereof of a therapeutically effective amount of a pyrido(3,2-d)pyrimidine derivative according to claim 31.

44. A method of prevention or treatment of a viral infection according to claim 43, wherein said viral infection is due to a member of the Flaviridae family.

45. A method of prevention or treatment of a viral infection according to claim 43, wherein said viral infection is due to hepatitis C virus.

46. A method of prevention or treatment of a viral infection according to claim 43, wherein said patient is a human being and said effective amount ranges from 0.01 mg to 20 mg per day per kg bodyweight.