Patent ID: 8080529

Claim:
A compound of Formula (I) wherein A is a bivalent radical selected from —NHC(O) and —C(O)NH—; R 1 is —OC(O)(CH 2 ) n NR 8 R 9 , —O—(CH 2 ) n NR 8 R 9 , —OC(O)N(R 7 )(CH 2 ) n NR 8 R 9 , —O(CH 2 ) n CN, —OC(O)(CH 2 ) n N(CH 2 ) n NR 8 R 9 , or —OC(O)CH═CH 2 with the proviso that if R 1 is —OC(O)CH═CH 2 , R 3 cannot be methyl; R 2 is hydrogen or a hydroxyl protecting group; R 3 is hydrogen, unsubstituted C 1-4 alkyl or C 1-4 alkyl substituted at terminal carbon atom with CN or NH 2 group, or C 1-5 alkanoyl; R 4 is hydrogen, C 1-4 alkyl or C 2-6 alkenyl; R 5 is hydroxy, methoxy group, —OC(O)(CH 2 ) n NR 8 R 9 or —O—(CH 2 ) n NR 8 R 9 , or —O(CH 2 ) n CN; R 6 is hydroxy; or R 5 and R 6 taken together with the intervening atoms form a cyclic group having the following structure: wherein Y is a bivalent radical selected from —CH 2 —, —CH(CN)—, —O—, —N(R 7 )— and —CH(SR 7 )—; R 7 is hydrogen or C 1-6 alkyl; R 8 and R 9 are each independently hydrogen, C 3-7 cycloalkyl, or C 1-18 alkyl, wherein C 1-18 alkyl is: (i) uninterrupted or interrupted by 1-3 bivalent radical groups selected from —O—, —S— and —N(R 7 )—; and/or (ii) unsubstituted or substituted by 1-3 groups selected from halogen, OH, NH 2 , N—(C 1 -C 6 )alkylamino, N,N-di(C 1 -C 6 -alkyl)amino, CN, NO 2 , OCH 3 , a C 3-8 membered non-aromatic ring which is saturated or unsaturated, a non-aromatic heterocyclic ring containing 2-6 carbon atoms which is saturated or unsaturated containing from 1-2 heteroatoms selected from oxygen, sulphur and nitrogen, alkylcarbonylalkoxy and alkoxycarbonylamino; or R 8 and R 9 taken together with nitrogen to which they are attached form a non-aromatic heterocyclic ring containing 2-6 carbon atoms which is: (iii) saturated or unsaturated containing from 0 or 1 additional heteroatoms selected from oxygen, sulphur and nitrogen; and/or (iv) unsubstituted or substituted by 1-2 groups selected from C 1-5 alkanoyl and C 1-6 alkyl, wherein C 1-6 alkyl is uninterrupted or is interrupted by 1-3 bivalent radical groups selected from —O—, —S— and —N(R 7 )—, and/or being unsubstituted or substituted by 1-2 groups selected from OH, NH 2 , a non-aromatic heterocyclic ring containing 2-6 carbon atoms which is unsubstituted or is substituted by group selected from C 1-4 alkyl, halo, NH 2 , OH, SH, C 1-6 alkoxy and C 1-4 hydroxyalkyl, a C 3-7 cycloalkyl which is unsubstituted or is substituted by group selected from C 1-4 alkyl, halo, NH 2 , OH, SH, C 1-6 alkoxy and C 1-4 hydroxyalkyl; n is an integer from 1 to 8 or a pharmaceutically acceptable salt thereof.