主权项 |
1. An isolated compound having the following formula: wherein
R1 is alkyl;R2 is H or alkyl;R3, R4, and R5 are independently —H, acyl, halo, haloalkyl, amino, alkylamino, hydroxyl, alkyl, hydroxylalkyl, or —COOH;R6 is —O or —NH;R7 is —H, alkyl, alkoxy, hydroxylalkyl, hydroxyl, or halo;R8, R9, and R12 are independently —H, acyl, halo, amino, alkylamino, hydroxyl, alkyl, hydroxylalkyl, or —COOH;R10 is H or alkyl; andR11 is H or alkyl. |