| abstract |
This invention provides compounds of Formula I, methods for their preparation and use for preparing compounds of Formula II n n n n n n n n n n n n wherein R 1 , R 2 , R 3 , R 5 , R 6 , X and n are as defined in the disclosure. n n n n n This invention also discloses preparation of compounds of Formula III n n n n n n n n n n n n wherein R 1 , R 2 , R 7 , R 8 , R 9 and n are as defined in the disclosure. n n n n n This invention also pertains to certain compounds of Formula 4 and 6 used to prepare compounds of Formula I. n n n n n n n n n n n n wherein R 1 , R 2 , R 5 , X and n are as defined in the disclosure. |