Patent ID: 6229015
Filing Date: 2001-05-08
Classification: A61P,C07D,Y02P

Abstract:
A process of preparing a compound of formula (I): ##STR10##wherein R.sup.1 and R.sup.2 are alkyl groups of 1 to 4 carbon atoms and n is from 2 to 5, which comprises reacting a 1-chloro-7-(protected hydroxy)-4-nitroacridin-9(10H)-one of formula (IV-P): ##STR11##wherein A is a hydroxy-protecting group removable by reduction, with an .omega.-(dialkylamino)alkylamine of formulaNH.sub.2 --(CH.sub.2).sub.n NR.sup.1 R.sup.2in which n, R.sup.1 and R.sup.2 are as defined above, to produce a 7-(protected hydroxy)-4-nitro-1-[[.omega.-(dialkylamino)alkyl]amino]acridin-9(10H)-one of formula (III-P): ##STR12##in which A, n, R.sup.1 and R.sup.2 are as defined above,reducing the compound of formula III-P at a temperature of from 15 to 50.degree. C. with either a hydrogen-provider comprising a reducing agent able to reduce the nitro substituent and deprotect the hydroxy group in formic acid solution, or with formate ions, in the presence of a palladium catalyst and formic acid, removing substantially all the residual palladium and heating the remaining reaction mixture to effect cyclisation to the corresponding compound of formula I.