| abstract |
A compound that has a general structure of formula I: ** Formula ** in which X is O, OCH2, OCH2CH> = CH or OCH2C≡C, Y is any one of formulas IIa-IIc: ** Formula ** in which it is a link to X and formula IIa comprises a ring having R2 as a substituent, and Z in formulas IIa-IIc is CH2, CH> = CH, C> = C or a direct bond, the numbers 2, 3 and 4 are ring positions in a terminal ring having R1 as a substituent, the terminal ring of formula I comprises C, CH or aza in each ring position and each of R1 and R2 of formulas I and IIa are one, two or three substituents located in any available ring position and are independently H, F, Cl, CF3, OCF2H, OCF3 or combinations thereof. |