摘要 |
The present invention is a compound of the formula <IMAGE> wherein R1 and R2 are independently C1-20 alkyl unsubstituted or substituted with a C1-3 alcohol, or allyl unsubstituted or substituted with a C1-4 alkyl or phenyl, R3 and R4 are independently hydrogen, or C1-20 alkyl unsubstituted or substituted with a C1-3 alcohol or together R3 and R4 are oxygen, and R5 and R6 are independently C1-20 alkyl unsubstituted or substituted with C1-3 alcohol or phenyl, hydroxy, -(CH2)1-3COOH, -CHR7COOH wherein R7 is C1-5 alkyl or C1-5 alkyl substituted with hydroxy, amino, or carboxy, or allyl unsubstituted or substituted with a C1-4 alkyl or phenyl or together R5 and R6 with the two nitrogen atoms form a fused ring having the formula <IMAGE> wherein n is 1 or 2, or form a fused ring having the formula <IMAGE> wherein p is an integer from 0 to 3.
|