Patent ID: 6870053

Claim:
A compound of formula (VI) wherein R 3 is hydrogen; hydroxyl or a protected hydroxyl; a C 3-7 carbocyclic group optionally substituted with one or more groups selected from C 1-4 alkyl, C 1-4 alkoxy, hydroxyl or protected hydroxyl, azido, phosphonyl, or halogen; an acyclic C 2-8 hydrocarbyl group, wherein carbon atoms may be substituted by one or more heteroatoms selected from N, O or S, and wherein such acyclic C 2-8 hydrocarbyl group may be optionally substituted with one or more groups selected from C 1-4 alkyl, C 1-4 alkoxy, hydroxyl or protected hydroxyl, azido, phosphonyl, or halogen; or a C 4-7 heterocyclic group, wherein one or more carbon atom is replaced by a N, O, or S atom and wherein such C 4-7 heterocyclic group may be optionally substituted with one or more groups selected from C 1-4 alkyl, C 1-4 alkoxy, hydroxyl or protected hydroxyl, azido, phosphonyl, or halogen; provided that such groups are not attached by a glycosidic bond.