Patent ID: 7517895

Claim:
A compound having the formula (I): wherein R 1 is OR 7 , or NHR 7 ; R 2 is H, Cl, Br, or I; R 3 is H, Br, I, phenyl, ethynyl, straight chain saturated alkyl, or straight chain unsaturated alkyl; R 4 is H, Br, I, phenyl, ethynyl, straight chain saturated alkyl, or straight chain unsaturated alkyl; R 5 is H, straight chain saturated alkyl, straight chain unsaturated alkyl, branched chain saturated alkyl, branched chain unsaturated alkyl, aryl, or substituted aryl; R 6 is O, NH, or S; X is O or S; Y is O, or NR 8 ; Z is H, 19-OH, or 21-OR 8 ; R 7 is H, straight chain saturated alkyl, straight chain unsaturated alkyl, acyl or aryl; and R 8 is H, straight chain saturated alkyl, straight chain unsaturated alkyl, acyl, or aryl.