主权项 |
1. A compound having a structure from Formula 1:wherein each of R1, R2 and R3 is independently selected from the group consisting of furan-2-yl, furan-3-yl, furan-4-yl, 4-halobenzyl, 3-halobenzyl, 5-halobenzyl, dihalobenzyl, trihalobenzyl, tetrahalobenzyl, pentahalobenzyl,wherein halo is fluoro, chloro, bromo or iodo; and with the proviso that when R3 is furanyl, R1 cannot be |