Patent ID: 8592427

Claim:
A compound having the formula: or its geometric isomers, enantiomers, diastereomers, racemates, pharmaceutically acceptable salts and solvates thereof; wherein represents a single or double bond; X is —S— or —O—; R 1 is selected from —C(O)OR 20 , —C(O)R 20 , —C(O)NR 20 R 21 , —PO 3 MY, —P(O) 2 (OR 20 )M and —P(O)(OR 20 )(OR 21 ); wherein each R 20 and R 21 is independently selected from hydrogen, aliphatic, substituted aliphatic, aryl or substituted aryl; Y and M are the same or different and each is a monovalent cation; or M and Y together is a divalent cation; each X 1 , X 2 , and X 3 is independently selected from absent, —C(O)—, —C(OR 10 )(R 11 )—, —[C(R 10 )(R 11 )] v —, —C(R 10 )(R 11 )═C(R 10 )(R 11 )—; wherein v is 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; each R 10 and R 11 is independently absent, hydrogen, halogen, aliphatic, substituted aliphatic, aryl or substituted aryl; alternatively two R 10 and R 11 together with the atoms to which they are attached may form an additional optionally substituted, 3, 4, 5, 6 or 7 membered ring; and t is 0, 1, 2 or 3.