Claims for Patent: 8,907,099

Summary for Patent: 8,907,099

Title:	Nitrocatechol derivatives as COMT inhibitors
Abstract:	New compounds of formula I are described. The compounds have potentially valuable pharmaceutical properties in the treatment of some central and peripheral nervous system disorders.
Inventor(s):	David Alexander Learmonth, Laszlo Erno Kiss, Pedro Nuno Leal Palma, Humberto Dos Santos Ferreira, Patricio Manuel Vieira Araújo Soares Da Silva
Assignee:	Bial Portela and Cia SA
Application Number:	US13/442,356
Patent Claims:	1. A compound according to formula IVA, IVB or IVC wherein R4, R5, R6 and R7 independently from each other represent hydrogen, C1-C6-alkyl, C1-C6-thioalkyl, C1-C6-alkoxy, C6-C12-aryloxy or a C6-C12-thioaryl group, C1-C6-alkanoyl or C7-C13-aroyl group, amino, C1-C6-alkylamino, C1-C6-dialkylamino, C3-C12-cycloalkylamino or C3-C12-heterocycloalkylamino, C1-C6-alkylsulphonyl or C6-C12-arylsulphonyl, halogen, C1-C6-haloalkyl, trifluoromethyl, cyano, nitro or a heteroaryl group; and R8 and R9 independently from each other represent hydrogen or suitable protective groups for aromatic hydroxyl groups. 2. A compound according to claim 1 wherein the suitable protective groups for aromatic hydroxyl groups are selected from methyl, ethyl, isopropyl, benzyl, 4-methoxybenzyl, methoxymethyl, benzyloxymethyl, methoxyethoxymethyl, tetrahydropyranyl, phenacyl, allyl, trimethylsilyl, tert-butyldimethylsilyl, benzyloxycarbonyl, tert-butoxycarbonyl, ester, sulphonate, carbamate, phosphinate, acetal and ketal derivatives. 3. A compound according to claim 1, wherein one of the groups R8 and R9 is hydrogen and the other is methyl. 4. A compound according to claim 1, wherein R8 represents methyl and R9 represents hydrogen. 5. A compound according to formula VIA, VIB or VIC wherein R4, R5, R6 and R7 independently from each other represent hydrogen, C1-C6-alkyl, C1-C6-thioalkyl, C1-C6-alkoxy, C6-C12-aryloxy or a C6-C12-thioaryl group, C1-C6-alkanoyl or C7-C13-aroyl group, amino, C1-C6-alkylamino, C1-C6-dialkylamino, C3-C12-cycloalkylamino or C3-C12-heterocycloalkylamino, C1-C6-alkylsulphonyl or C6-C12-arylsulphonyl, halogen, C1-C6-haloalkyl, trifluoromethyl, cyano, nitro or a heteroaryl group; and R8 and R9 independently from each other represent hydrogen or suitable protective groups for aromatic hydroxyl groups. 6. A compound according to claim 5 wherein the suitable protective groups for aromatic hydroxyl groups are selected from methyl, ethyl, isopropyl, benzyl, 4-methoxybenzyl, methoxymethyl, benzyloxymethyl, methoxyethoxymethyl, tetrahydropyranyl, phenacyl, allyl, trimethylsilyl, tert-butyldimethylsilyl, benzyloxycarbonyl, tert-butoxycarbonyl, ester, sulphonate, carbamate, phosphinate, acetal and ketal derivatives. 7. A compound according to claim 5 wherein one of the groups R8 and R9 is hydrogen and the other is methyl. 8. A compound according to claim 5 wherein R8 represents methyl and R9 represents hydrogen.