              !" Rafat Ali § , Gajendra Singh ±,‡ , Shalini Singh § , Ravi. S. Ampapathi* ,±,‡ and Wahajul Haq.* ,±,§ . § Medicinal and Process Chemistry Division and ‡ NMR Centre, SAIF, CSIR)Central Drug Research Institute, Lucknow, Uttar Pradesh 226031, India , ± Academy of Scientific and Innovative Research, New Delhi)11000, India. #   "$"   $" " !  % %" &’       %( )    * ) * )  &#  % $+,  - ." +   /0