| abstract |
A compound of formula (I): (see formula I) wherein: R1 is -SR10, -O-C(O)-R11, -NR12R13, where R10 is a C1-8-alkyl group or a phenyl group unsubstituted or substituted by a C1-4-alkyl group, R11 is a thiophenenyl, furanyl or pyrrolyl group, R12 is H or a C1-4-alkyl group and R13 is a C1-8-alkyl group or a phenyl group unsubstituted or substituted by a C1-4-alkyl group; R2 is H or a C1-4-alkyl group; R3 and R4 are independently H or C1-4-alkyl groups; R5 and R6 are independently H, OH or OR14, or taken together are =O, where R14 is a protecting group; R7 is H or a C1-4-alkyl group; and, R8 is H, R9 is OH and R15 is H, or R15 is H and R8 and R9 taken together are -O-, or R9 is OH and R8 and R15 taken together form a bond; and, R18 and R19 are both H, or R18 and R19 taken together form a bond, or a plant physiologically acceptable salt thereof is useful for inhibiting 9-cis-epoxycarotenoid dioxygenase (NCED) in a plant or seed and is therefore useful for regulating ABA biosynthesis in the plant or seed. |