c) converted by a reaction where the trimethylsilyl group is replaced by hydrogen, a deoxohalogenation reaction, a reaction where the T group as defined in formula VI is converted to ???NHR4 wherein R4 is as defined above in formula I, and finally a hydrolytic reaction to obtain a compound of formula V wherein R1, R3 and R4 are as defined above in formula I, and Halo is a halogen atom, and optiona