Oxidated derivatives of triazolylpurines useful as ligands of the adenosine A2A receptor and their use as medicaments

1. A process for synthesizing a compound of the formula

or an optically active form, or a pharmaceutically acceptable salt thereof, wherein

R 1 is C 1 -C 6 linear or branched alkyl;

R 2 is a group of formula:

R 9 —(CHR 8 ) p —(CR 6 R 7 ) m —(CR 4 R 5 ) n —;

R 4 and R 5 are H;

R 6 and R 8 are at any occurrence independently H or ═O with the meaning of carbonyl; with at least one of R 6 and R 8 being ═O with the meaning of carbonyl;

R 7 and R 9 are at any occurrence independently H or are absent in case the corresponding carbon atom bearing said R 6 or R 8 group is involved in a carbonyl bond;

m and p are independently an integer comprised between 0 and 2;

n is 1 or 2;

m+n+p≧4;

R 3 is NH 2 or NHR 10 ;

R 10 is linear or branched C 1 -C 6 alkyl; linear or branched C 1 -C 6 hydroxyalkyl; linear or branched (C 1 -C 3 )alkoxy(C 1 -C 6 )alkyl; amino(C 1 -C 6 )alkyl, where the amino group is optionally substituted with one or two linear or branched C 1 -C 3 alkyl groups; C 6 -C 14 aryl; or C 6 -C 14 aryl(C 1 -C 6 )alkyl, wherein said C 6 -C 14 aryl group is optionally substituted by one or more substituents, which are the same or different, selected from the group consisting of halogen; hydroxyl; linear or branched, saturated or unsaturated C 1 -C 6 alkoxy; and amino, where the amino group is optionally substituted with one or two linear or branched C 1 -C 6 alkyl groups

comprising the reaction between a compound of formula II

wherein

R 1 is C 1 -C 6 linear or branched alkyl;

R 11 is N (R 13 ) 2 ;

R 13 is benzyl, p-(MeO)-benzyl, p-(Cl)-benzyl or p-(Br)-benzyl;

R 12 is Cl;

and a compound of formula IV

H—(CH 2 ) q —(CR 6b R 6c ) r —(CH 2 ) s -MgX  Formula IV,

wherein

X is Cl or Br;

R 6b and R 6c are at any occurrence independently both H or when taken together with the carbon atom to which they are attached to form a 1,3-dioxane group optionally substituted by two or more methyl groups with at least one of the occurrence being a 1,3-dioxane group optionally substituted by two or more methyl groups;

q is an integer comprised between 0 and 3;

r and s are independently an integer comprised between 1 and 3; with q+r+s≧4;

in the presence of a Fe(acac) 3 in an aprotic solvent at a temperature ranging from 0° C. to room temperature.

2. Process according to claim 1 wherein the aprotic solvent is THF or NMP.