propaldehyde sentence in Hindi

The preparation of L-( " R " )-coniine by the reduction of ?-coniceine ( L-propenylpiperidine ) by L�ffler and Friedrich incorrectly, that pelletierine was the aldehyde ( ?-2-piperidyl-propaldehyde ) corresponding to coniine, and yielded " rac-" coniine when its hydrazone was heated with sodium ethoxide in ethanol at 156 170 �C . According to these authors, D-( " S " )-coniine is rendered almost optically inactive when heated with barium hydroxide and alcohol at 180 230 �C . Leithe has shown by observation of the optical rotation of ( + )-pipecolic acid ( piperidine-2-carboxylic acid ) and some of its derivatives under varying conditions, that it must belong to the D-series of amino acids.