Patent ID: 8188274

Claim:
A process for preparing a compound of general formula R a denotes a benzyl, 1-phenylethyl or 3-chloro-4-fluorophenyl group, R b denotes a methyl, ethyl, isopropyl, cyclopropyl, 2-methoxyethyl, tetrahydrofuran-3-yl, tetrahydrofuran-2-yl-methyl, tetrahydrofuran-3-yl-methyl, tetrahydropyran-4-yl or tetrahydropyran-4-yl-methyl group, R c denotes a methyl, ethyl or 2-methoxyethyl group or R b and R c together with the nitrogen atom to which these groups are bound denotes a morpholino or homomorpholino group optionally substituted by one or two C 1-3 -alkyl groups, R d denotes a cyclopropylmethyl, cyclobutyl, cyclopentyl, tetrahydrofuran-3-yl, tetrahydrofuran-2-yl-methyl, tetrahydrofuran-3-yl-methyl, tetrahydropyran-4-yl or tetrahydropyran-4-yl-methyl group, and R 1 and R 2 each independently of one another denote a C 1-4 -alkyl group, comprising the following process steps: a) reacting 7-chloro-6-nitro-3H-quinazolin-4-one with a primary amine of formula R a —NH 2 (XV), wherein R a denotes a benzyl, 1-phenylethyl or 3-chloro-4-fluorophenyl group, in the presence of POCl 3 , b) converting the resulting compound of general formula into the sulphonyl derivative of formula wherein R 3 denotes a C 1-4 -alkyl group wherein the hydrogen atoms may be wholly or partly replaced by fluorine atoms, or a phenyl group optionally substituted by one to three substituents selected from C 1-3 -alkyl groups, halogen atoms, particularly fluorine, chlorine or bromine atoms, cyano or nitro groups, while the substituents may be identical or different, and wherein R a in the two formulae (X) and (XIII) has the meanings given under a), c) converting the sulphonyl derivative of formula (XIII) into a compound of formula by reacting with an alcohol of formula R d —OH (XVI) in the presence of a base, wherein R a has the meanings given under a) and R d denotes a cyclopropylmethyl, cyclobutyl, cyclopentyl, tetrahydrofuran-3-yl, tetrahydrofuran-2-yl-methyl, tetrahydrofuran-3-yl-methyl, tetrahydropyran-4-yl or tetrahydropyran-4-yl-methyl group, d) reducing the compound of formulae (XI) thus obtained to the amino derivative of formula wherein R a has the meanings given under a) and R d has the meanings given under c), e) converting the amino derivatives of formula (XII) into the phosphonic ester of formula wherein R a has the meanings given under a) and R d has the meanings given under c), R 1 and R 2 each independently of one another denote a C 1-4 -alkyl group, f) reacting the resulting phosphonic ester of formula (III) with a hydrogen sulphite adduct of formula wherein M+ denotes a cation, and R b denotes a methyl, ethyl, isopropyl, cyclopropyl, 2-methoxyethyl, tetrahydrofuran-3-yl, tetrahydrofuran-2-yl-methyl, tetrahydrofuran-3-yl-methyl, tetrahydropyran-4-yl or tetrahydropyran-4-yl-methyl group, R c denotes a methyl, ethyl or 2-methoxyethyl group or R b and R c together with the nitrogen atom to which these groups are bound denote a morpholino or homomorpholino group optionally substituted by one or two C 1-3 -alkyl groups.