Patent ID: 8853270

Claim:
A compound represented by the structural formula: wherein: the zigzag line indicates that the compound can be cis or trans; X is selected from hydroxyl, nitro, aryl, heteroaryl, alkyl, alkoxy, CHO, COR, halogen, haloalkyl, NH 2 , NHR, NRR′, SR, CONH 2 , CONHR, CONHRR′, O-aryl, O-heteroaryl or O-ester; R 1 is selected from alkyl, CHO, alkoxy, NH 2 , NHR, NRR′, SR, CF 3 or halogen; R 2 and R 3 are independently selected from hydrogen, alkyl, alkoxy, hydroxyl, NH 2 , NHR, NRR′, SR, haloalkyl or halogen; R 4 and R 5 are independently selected from hydrogen, alkyl, CH 2 NHCOR″ or CH 2 CONHR″; and, R 6 , R 7 and R 8 are either all alkyl or all alkoxy; wherein at least one of the substituents R 4 and R 5 is an alkyl group; and wherein R and R′ are independently selected from C 1-10 alkyl groups and R″ is a C 1-10 alkyl group, aryl group or heteroaryl group; or a salt, an ester, a free acid or base or a hydrate thereof.