1. A compound of Formula I
or its stereoisomers, pharmaceutically acceptable salts, complexes, hydrates, solvates, tautomers, polymorphs, racemic mixtures, optically active forms and pharmaceutically active derivative thereof, wherein
R1 is selected from the group consisting of hydrogen, C1-6 alkyl, C2-6 alkenyl, and C3-C6 cycloalkyl, each of which is unsubstituted or substituted with 1 to 3 groups independently selected from halogen, amino, hydroxy, oxetane, -OC1-6 alkyl, C3-6 cycloalkylamino, C1-6 alkylamino, or di(C1-6 alkyl)amino;
R2 is selected from the group consisting of hydrogen, hydroxyl, and amino; X is -NH, -NC1-6 alkyl, O, or CR3R4;
R3 and R4 are independently selected from the group consisting of hydrogen, halogen, and C1-6 alkyl; Y1 is N or CR5;
R5 is selected from the group consisting of hydrogen, halogen, cyano, -OC1-6 alkyl, -OC1-6 haloalkyl, and C1-6 alkyl; Y2 is N or CH; Y3 is N or CR6;

R6 is selected from the group consisting of hydrogen, halogen, cyano, C1-6 alkyl, -OC1-6
alkyl, and -OC1-6 haloalkyl;
Z1 is NH when Z2 is C1-6 alkylene; or Z1 is C1-6 alkylene when Z2 is NH;
n is 1 or 2;
W is CH2 wherein dotted line (----) represents no bond; W is O when dotted line (----)
represents either a bond or no bond;
Ring A is selected from the group consisting of
2. A compound as claimed in claim 1, or its stereoisomers, pharmaceutically acceptable
salts, complexes, hydrates, solvates, tautomers, polymorphs, racemic mixtures, optically
active forms and pharmaceutically active derivative thereof
wherein
R1 is selected from the group consisting of hydrogen, C1-6 alkyl, C2-6 alkenyl, and C3-6
cycloalkyl, wherein alkyl is optionally substituted with 1 to 3 groups independently
selected from fluorine, hydroxy, amino, oxetane, -OC1 alkyl, C3-6 cycloalkylamino, C1-2
alkylamino, or di(C1-2 alkyl)amino;
R2 is selected from the group consisting of hydrogen, hydroxyl, and amino;
X is -NH, -NC1 alkyl, O, or CR3R4;
R3 and R4 are independently selected from the group consisting of hydrogen, fluorine, and
C1 alkyl;
Y1 is N or CR5;
R5 is selected from the group consisting of hydrogen, fluorine, chlorine, cyano, -OCH3, -

OCF3, OCHF2, and C1 alkyl;
Y2 is N or CH;
Y3 is N or CR6;
R6 is selected from the group consisting of hydrogen, fluorine, cyano, -OCH3, - OCHF2,
and -OCF3;
Z1 is NH when Z2 is CH2; or Z1 is CH2, CH2CH2 or CH(OH)CH2 when Z2 is NH;
n is 1 or 2
W is O when dotted line (----) represents either a bond or no bond;
Ring A is selected from the group consisting of