| abstract |
In one aspect, the invention relates to a process for preparing a compound of formula (XII), wherein PG is a protecting group, or a compound of formula (XI), comprising the steps of: (i) treating a compound of formula XIII, wherein PG is a protecting group, with N- methylpiperazine to form a compound of formula XII, wherein said compound of formula XII is in the form of a mixture of cis and trans isomers; (ii) combining the mixture formed in step (i) with an organic solvent and heating the solvent mixture so formed; (iii) isolating the trans-isomer of the compound of formula XII from the solvent mixture formed in step (ii); and (iv) optionally treating said trans-isomer of the compound of formula XII with an acid to form a compound of formula XI; and isolating said compound of formula XI. Further aspects of the invention relate to processes for preparing pyrimido-diazepinone derivatives using the above process and intermediates. |