Diebenzofuran derivatives as inhibitors of PDE-4 and PDE-10

A compound of formula

• and its tautomers, stereoisomers, enantiomers, diastereomers, and pharmaceutically acceptable salts wherein
• R1 is
• X1 is selected from hydrogen, optionally substituted alkyl, optionally substituted N,N-dimethylaminoalkenyl, carboxy, ═CH—NR5R6, COOR6;
• X2 is selected from optionally halo, cyano, carboxy, COOR6, substituted alkyl, NR5R6, —NR5S(O)mR6;
• X4 represents O, S, NR5, N—OR5, ═N—OCH2COOH, ═N—O-Me;
• when X1 and X2 or X1 and X4;
• are ortho to each other, they may together form a 4 to 7 membered ring system selected from an alicyclic or heterocyclic ring;
• r is 0 or 1;
• R2 represents optionally substituted groups selected from alkyl, haloalkyl, alkenyl, alkynyl, optionally substituted cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl or optionally substituted heterocyclyl;
• R5 represents hydrogen, alkoxy, R′COOR6, optionally substituted alkyl or optionally substituted aryl;
• R6 represents hydrogen, optionally substituted alkyl or optionally substituted aryl;
• R5 and R6 may together form a 3 to 12 membered mono or polycyclic ring;
• R′ represents a direct bond or an optionally substituted alkylene;
• m is an integer represented by 0, 1 or 2.