摘要:
The invention relates to compounds of formula (X), and salts thereof, and their use as intermediates in improved manufacturing processes for the synthesis of pharmaceutical compound of formula (I): X is =0, =N-0H or =N-OC(O)Me; Y is hydrogen, PhS- or p -chlorophenylsulfanyl; Z is hydrogen or -CH 2 COOR 1 wherein R 1 is selected from hydrogen, optionally substituted hydrocarbyl and optionally substituted heterocyclyl.