Patent ID: 6906046

Claim:
A compound of formula (I) and optical isomers, diastereomers, enantiomers and pharmaceutically acceptable salts thereof in isolation or mixture, where, independently at each location: R 1 is selected from the following six formulae: R 2 is —OR 9 or —NR 9 R 9 ; R 3 is selected from hydrogen, halogen, hydroxyl or protected hydroxyl, amino or protected amino, and C 1 -C 8 alkyl or C 1 -C 8 haloalkyl; R 4 and R 5 are independently selected from R 9 , —OR 9 , —NR 9 R 9 and —N═N—R 9 , or R 4 and R 5 may together form a group selected from ═O, ═CR 8 R 8 and ═NR 10 , or R 4 and R 5 may together with the carbon to which they are both attached form a spiro carbocyclic or heterocyclic ring; R 6 is selected from hydrogen, inorganic groups having 1-8 atoms selected from boron, sulfur, phosphorous, silicon and hydrogen, and organic groups having 1-20 carbons and optionally containing 1-4 heteroatoms selected from nitrogen, oxygen and silicon: R 7 is selected from halogen, hydroxyl or protected hydroxyl, amino or protected amino, and C 1 -C 8 alkyl or C 1 -C 8 haloalkyl; R 8 is selected from hydrogen, alkyl, aryl and heteroalkyl; R 9 is selected from hydrogen and organic groups having 1-30 carbons and optionally containing 1-4 heteroatoms selected from nitrogen, oxygen and silicon, with the provision that two R 9 groups both joined to a common atom may be joined together so as to form a ring with the common atom; R 10 is selected from —R 9 , —OR 9 , —NR 9 R 9 , —NH—C(O)R 9 ; —NH—C(O)OR 9 and —NH—C(S)NHR 9 ; and n is 0, 1, 2 or 3; with the proviso that when R 6 is hydrogen, methyl, or ethyl and R 4 and R 5 together form ═O or R 4 is hydrogen and R 5 is hydroxy, R 1 is —C(O)OR 9 , then R 2 is not —OH, —OCH 3 , OR —OCH 2 CH 3 .