Process for the preparation of a compound of formula Iin the form of a single stereoisomer in crystalline form, comprising deprotecting the amine group in a compound of formula IIaor in a mixture of a compound of formula IIa with a compound of formula IIband isolating a compound of formula I from the reaction mixture； compounds and salts of compounds of formula I in crystalline form； pharmaceutical compositions comprising such salts； processes for the preparation of intermediates and intermediates in a process for the preparation of a compound of formula I.結晶狀之單一種立體異構物形式的式I所示之化合物的製法，其包含：將式IIa所示之化合物中的胺基或式IIa所示之化合物和式IIb所示之化合物的混合物中之胺基脫保護及從該反應混合物中單離出式I所示之化合物；結晶狀的式I所示之化合物和化合物的鹽類；含有該鹽類的藥學組成物；中間物的製法和在式I所示之化合物的製法中的中間物。
