received by the International Bureau on 07 April 2017 (07.04.17)

[Claim 1] [Amended] Derivatives of 2,4-diamino-6-ethylpyrimidine of Formula

(I) :

(I)

Wherein X_{l 5} X₂ are oxygen, Y_{l 5} Y₂ are (CH₂)_{1 3}alkyl, Z is

(l-substituted- lH-l,2,3-triazol-4-yl) ring, (3-(substituted)isoxazol-5-yl) ring, (2-(substituted)oxazol-4-yl) ring, (2-(substituted)thiazol-4-yl) ring; wherein Ar is an aromatic ring or substituted aromatic ring as below:

a. Z is a ring of (l-substituted-lH- l,2,3-triazol-4-yl); Ar is phenyl or carboxyl-substitutedphenyl; no group X_{l 5} X₂, Yi and Y₂

b. Z is a ring of (l-substituted-lH- l,2,3-triazol-4-yl); Ar is phenyl, car- boxymethyl-substitutedphenyl, carboxyl-substitutedphenyl or diphenyl- carbamoyl-substitutedphenyl; Y₂ is Ci_₃ alkyl [(CH₂)_{1 3}]; no group X_{l 5} X

c. Z is a ring of (l-substituted-lH- l,2,3-triazol-4-yl); Ar is chloro- substitutedphenyl or carboxymethyl-substitutedphenyl; X₂ is oxygen; Y 2 is C_{2 3} alkyl [(CH₂)_{2 3}];; no group Xi and Yi

d. Z is a ring of (3-(substituted)isoxazol-5-yl); Ar is phenyl, fluoro- sub stitutedpheny 1, chloro- s ub stitutedpheny 1, bromo- s ub stitutedpheny 1, trifluoromethyl-substitutedphenyl, methoxy-substitutedphenyl, nitro- substitutedphenyl, cyano-substitutedphenyl, carboxymethyl-substi- tutedphenyl or carboxyl-substitutedphenyl; Xi is oxygen; Yi is Ci_₃ alkyl [(CH₂)_{1 3}]; no group X₂ and Y₂

e. Z is a ring of (2-(substituted)oxazol-4-yl); Ar is phenyl, chloro- sub stitutedpheny 1, methyl- s ub stitutedpheny 1, nitro- s ub stitutedpheny 1, alkoxycarbonylmethoxy-substitutedphenyl, carboxymethoxy-substitut- edphenyl, alkoxycarbonyl-substitutedphenyl or carboxy-sub- stitutedphenyl; is oxygen; is Ci_₂ alkyl [(CH₂)_{1 2}]; no group X₂ and Y₂

f. Z is a ring of (2-(substituted)thiazol-4-yl); Ar is phenyl, fluoro- substitutedphenyl,

chloro-substitutedphenyl, bromo- sub stitutedpheny 1, methyl- substitutedphenyl methoxy-substitutedphenyl, nitro-substitutedphenyl, alkoxycarbonylmethoxy-substitutedphenyl, carboxymethoxy-substitut- edphenyl, alkoxycarbonyl-substitutedphenyl or carboxyl-sub- stitutedphenyl; is oxygen; is Ci_₂ alkyl [(CH₂)_{1 2}]; no group X₂ and

Y₂

[Claim 2] [unchanged] Formulations of compounds of Formula (I) for inhibition of Plasmodium falciparum comprise of one or more compounds according to claim 1 or their salts and pharmaceutically acceptable ex- cipients.

[Claim 3] [unchanged] Formulations of compounds of Formula (I) for inhibition of Plasmodium falciparum according to claim 2, wherein the said salt is hydrochloride salt.

[Claim 4] [amended] The derivative compounds of

2,4-diamino-6-ethylpyrimidine of claim 1, wherein said compounds are compound 1 to compound 56 below:

(1) 2,4-diamino-6-ethyl-5-(l-phenyl-lH-l,2,3-triazol-4-yl)pyrimidine (2)

2,4-diamino-6-ethyl-5-(l-(3-(carboxy)phenyl)-lH-l,2,3-triazol-4-yl)py rimidine

(3) 2,4-diamino-6-ethyl-5-( 1 -benzyl- 1H- 1 ,2,3-triazol-4-yl)pyrimidine (4)

2,4-diamino-6-ethyl-5-(l-((4-(carboxymethyl)phenyl)methyl)-lH- 1,2,3

-triazol-4-yl) pyrimidine

(5)

2,4-diamino-6-ethyl-5-(l-((4-(carboxy)phenyl)methyl)-lH-l,2,3-triazol

-4-yl) pyrimidine

(6)

2,4-diamino-6-ethyl-5-(l-((4-(diphenylcarbamoyl)phenyl)methyl)-lH-l

,2,3 -triazol-4- y l)pyrimidine

(7)

2,4-diamino-6-ethyl-5-(l-(phenylethyl)-lH-l,2,3-triazol-4-yl)pyrimidin e

(8)

2,4-diamino-6-ethyl-5-(l-(3-phenylpropyl)-lH-l,2,3-triazol-4-yl)pyrim idine

(9)

2,4-diamino-6-ethyl-5-(l-(2-(4-(chloro)phenoxy)ethyl)-lH-l,2,3-triazol -4-yl) pyrimidine (10)

2,4-diamino-6-ethyl-5-(l-(2-(4-(carboxymethyl)phenoxy)ethyl)-lH-l,2

,3-triazol-4-yl)pyrimidine

(I D

2,4-diamino-6-ethyl-5-(l-(3-(4-(chloro)phenoxy)propyl)-lH-l,2,3-triaz ol-4-yl) pyrimidine

(12)

2,4-diamino-6-ethyl-5-(l-(3-(4-(carboxymethyl)phenoxy)propyl)-lH-l,

2.3- triazol-4-yl)pyrimidine

(13)

2.4- diamino-6-ethyl-5-((3-(phenyl)isoxazol-5-yl)methoxy)pyrimidine (14)

2,4-diamino-6-ethyl-5-((3-(4-(fluoro)phenyl)isoxazol-5-yl)methoxy)pyr imidine

(15)

2,4-diamino-6-ethyl-5-((3-(4-(chloro)phenyl)isoxazol-5-yl)methoxy)py rimidine

(16)

2,4-diamino-6-ethyl-5-((3-(4-(bromo)phenyl)isoxazol-5-yl)methoxy)py rimidine

(17)

2,4-diamino-6-ethyl-5-((3-(3-(trifluoromethyl)phenyl)isoxazol-5-yl)met hoxy) pyrimidine

(18)

2,4-diamino-6-ethyl-5-((3-(3-(methoxy)phenyl)isoxazol-5-yl)methoxy) pyrimidine

(19)

2,4-diamino-6-ethyl-5-((3-(3-(nitro)phenyl)isoxazol-5-yl)methoxy)pyri midine

(20)

2,4-diamino-6-ethyl-5-((3-(3-(carboxy)phenyl)isoxazol-5-yl)methoxy)p yrimidine

(21)

2,4-diamino-6-ethyl-5-((3-(4-(trifluoromethyl)phenyl)isoxazol-5-yl)met hoxy) pyrimidine

(22)

2,4-diamino-6-ethyl-5-((3-(4-(methoxy)phenyl)isoxazol-5-yl)methoxy) pyrimidine (23)

2,4-diamino-6-ethyl-5-((3-(4-(nitro)phenyl)isoxazol-5-yl)methoxy)pyri midine

(24)

2,4-diamino-6-ethyl-5-((3-(4-(carboxy)phenyl)isoxazol-5-yl)methoxy)p yrimidine

(25)

2,4-diamino-6-ethyl-5-(3-(3-(4-(chloro)phenyl)isoxazol-5-yl)propoxy)p yrimidine

(26)

2,4-diamino-6-ethyl-5-(3-(3-(3-(trifluoromethyl)phenyl)isoxazol-5-yl)p ropoxy) pyrimidine

(27)

2,4-diamino-6-ethyl-5-(3-(3-(3-(cyano)phenyl)isoxazol-5-yl)propoxy)p yrimidine

(28)

2,4-diamino-6-ethyl-5-(3-(3-(3-(carboxymethyl)phenyl)isoxazol-5-yl)p ropoxy) pyrimidine

(29)

2,4-diamino-6-ethyl-5-(3-(3-(3-(carboxy)phenyl)isoxazol-5-yl)propoxy

)pyrimidine

(30)

2,4-diamino-6-ethyl-5-((2-(phenyl)oxazol-4-yl)methoxy)pyrimidine (3D

2,4-diamino-6-ethyl-5-((2-(3-(methyl)phenyl)oxazol-4-yl)methoxy)pyri midine

(32)

2,4-diamino-6-ethyl-5-((2-(3-(nitro)phenyl)oxazol-4-yl)methoxy)pyrim idine

(33)

2,4-diamino-6-ethyl-5-((2-(3-(benzyloxycarbonylmethoxy)phenyl)oxaz ol-4-yl) methoxy)pyrimidine

(34)

2,4-diamino-6-ethyl-5-((2-(3-(carboxymethoxy)phenyl)oxazol-4-yl)met hoxy) pyrimidine

(35)

2,4-diamino-6-ethyl-5-((2-(4-(cholro)phenyl)oxazol-4-yl)methoxy)pyri midine 2,4-diamino-6-ethyl-5-((2-(4-(benzyloxycarbonylmethoxy)phenyl)oxaz ol-4-yl) methoxy)pyrimidine

(37)

2,4-diamino-6-ethyl-5-((2-(4-(carboxymethoxy)phenyl)oxazol-4-yl)met hoxy) pyrimidine

(38)

2,4-diamino-6-ethyl-5-(2-(2-(phenyl)oxazol-4-yl)ethoxy)pyrimidine (39)

2,4-diamino-6-ethyl-5-(2-(2-(4-(carboxy)phenyl)oxazol-4-yl)ethoxy)py rimidine

(40)

2,4-diamino-6-ethyl-5-((2-(phenyl)thiazol-4-yl)methoxy)pyrimidine (41)

2,4-diamino-6-ethyl-5-((2-(3-(methyl)phenyl)thiazol-4-yl)methoxy)pyri midine

(42)

2,4-diamino-6-ethyl-5-((2-(3-(nitro)phenyl)thiazol-4-yl)methoxy)pyrim idine

(43)

2,4-diamino-6-ethyl-5-((2-(3-(benzyloxycarbonylmethoxy)phenyl)thiaz ol-4-yl) methoxy)pyrimidine

(44)

2,4-diamino-6-ethyl-5-((2-(3-(carboxymethoxy)phenyl)thiazol-4-yl)met hoxy) pyrimidine

(45)

2,4-diamino-6-ethyl-5-((2-(3-(carboxymethyl)phenyl)thiazol-4-yl)meth oxy) pyrimidine

(46)

2,4-diamino-6-ethyl-5-((2-(3-(carboxy)phenyl)thiazol-4-yl)methoxy)py rimidine

(47)

2,4-diamino-6-ethyl-5-((2-(4-(methyl)phenyl)thiazol-4-yl)methoxy)pyri midine

(48)

2,4-diamino-6-ethyl-5-((2-(4-(methoxy)phenyl)thiazol-4-yl)methoxy)p yrimidine

(49) 2,4-diamino-6-ethyl-5-((2-(4-(fluoro)phenyl)thiazol-4-yl)methoxy)pyri midine

(50)

2,4-diamino-6-ethyl-5-((2-(4-(chloro)phenyl)thiazol-4-yl)methoxy)pyri midine

(51)

2,4-diamino-6-ethyl-5-((2-(4-(bromo)phenyl)thiazol-4-yl)methoxy)pyri midine

(52)

2,4-diamino-6-ethyl-5-((2-(4-(benzyloxycarbonylmethoxy)phenyl)thiaz ol-4-yl) methoxy)pyrimidine

(53)

2,4-diamino-6-ethyl-5-((2-(4-(carboxymethoxy)phenyl)thiazol-4-yl)met hoxy) pyrimidine

(54)

2,4-diamino-6-ethyl-5-((2-(4-(carboxymethyl)phenyl)thiazol-4-yl)meth oxy) pyrimidine

(55)

2,4-diamino-6-ethyl-5-((2-(4-(carboxy)phenyl)thiazol-4-yl)methoxy)py rimidine

(56)

2,4-diamino-6-ethyl-5-(2-(2-(phenyl)thiazol-4-yl)ethoxy)pyrimidine