| 摘要 |
New gamma-substd. butenolide derivs. are cpds. of formula (I). In (I) X is CH2 or a direct bond; R1 and R2 are each H, 1-5C alkyl or opt. substd. aryl, or R1 and R2 together with the adjacent C-atoms form an o-phenylene residue of formula (Ia); when R1 and R2 are H, 1-5C alkyl or aryl, then R' and R" together with the adjacent C-atoms form a divalent residue of formula (Ib), (Ic) or (Id); and when R1 and R2 together form a residue (Ia), then R' and R" are each H, 1-5C alkyl or opt. substd. aryl, or together with the adjacent C-atoms form a divalent residue of (Ib), (Ic), (Id) or (Ie). Y is 2 H-atoms, an additional C-C bond, or an epoxy gp.; R''' is H, 1-5C alkyl or opt. substd. aryl; and the benzene rings A and B opt. carry one or more substituents selected from 1-8C alkyl, 1-8C alkoxy, halogen, aryl and aralkyl, or a fused-on benzene or heterocyclic ring. (I) are herbicides with activity against weeds and parasitic weeds such as Orobauche species (broomrapes) and Striga species. Certain cpds. (I) also have activity as germination stimulants. |
