| abstract |
This invention relates to a compound of Formula I, a method for its preparation and its use in the preparation of a compound of Formula II wherein R1, R2, R3, X and n are as defined in the disclosure. This invention also discloses preparation of compounds of Formula III wherein R1, R2, R6, R7, R8 and n are as defined in the disclosure. Also disclosed are certain intermediates of Formula 4 for the preparation of compounds of Formula I wherein X is N and R2, R3 and n are as defined in the disclosure. |