Novel heterocyclic compounds

Compound of the general Formula (I′)

• their tautomeric forms, their stereoisomers, their pharmaceutically acceptable salts, and pharmaceutical compositions containing them wherein Each of R1, R2, R3 and R4 at each occurrence independently represents H, halogen, hydroxyl, CN, NO2, CHO, COOH, CO, optionally substituted groups selected from, alkyl, alkoxy, thiol, sulphoxide, sulphone, acyl, NH2 or optionally substituted NHCO-linear or branched (C1-C6)alkyl, aralkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, hetererocyclylalkyl, heteroaryl, heteroaralkyl or the groups OR, C(O)OR, C(O)R, and SO2R wherein ‘R’ at each occurrence independently represents optionally substituted groups selected from H, linear or branched (C1-C6)alkyl, aryl, aralkyl, cycloalkyl, cycloalkylalkyl, heterocyclyl, hetrerocyclylalkyl, heteroaryl, heteroaralkyl groups;
• ‘A’ is selected from 3-7 member partially saturated, unsaturated or saturated ring which may further having one or more than one heteroatom selected from O, S, or N;
• Each of ‘E’ & ‘D’ is independently either nitrogen or carbon;
• ‘F’ is selected from C, N or O;
• Each of ‘n’, ‘r’ and ‘s’ independently represents an integer ranging from 0 to 6;