| abstract |
SUMMARY OF THE INVENTION The present invention provides a compound of formula (I) having structure (I): Wherein R 1 and R 2 are independently hydrogen, alkyl having 1 to 6 carbons, benzyl, acyl having 2 to 7 carbons, benzoyl, (1) or (2): X is hydrogen, alkyl having 1 to 6 carbons, CN, halogen, trifluoromethyl, or thioalkyl having 1 to 6 carbons; n = 1 to 3; provided that at least one of R 1 or R 2 is (1) or Or (2)] or a pharmaceutically acceptable salt thereof. |