Abstract: Compounds of formula (I): ##STR1## (wherein: R.sup.1 represents a hydrogen atom or a halogen atom;R.sup.2 represents a C.sub.1 -C.sub.6 alkyl group; andA represents an oxygen atom, a sulphur atom, a sulphinyl group or a sulphonyl group)have good insecticidal activity coupled with a low toxicity to warm-blooded animals. Compounds in which A represents an oxygen or sulphur atom can be prepared by reacting a corresponding alkali metal alkoxide or mercaptide with the corresponding 3-dimethylcarbamoyloxy-5-halomethylisoxazole derivative, while compounds where A represents a sulphinyl or sulphonyl group may be prepared by oxidizing the corresponding compound wherein A represents a sulphur atom. The compounds may be formulated with conventional insecticidal carriers or diluents and exhibit a synergistic increase in activity when combined with various known organic phosphate and carbamate insecticides.

Abstract: Compounds of formula (I): ##STR1## (wherein R.sup.1 represents a hydrogen or halogen atom R.sup.2 represents an alkyl, alkenyl, alkynyl, optionally substituted aralkyl or optionally substituted aryl group and A represents a sulphur atom or a sulphinyl or sulphonyl group) have insecticidal and acaricidal activity and, when formulated in suitable compositions for agricultural or horticultural use, can be used to protect plants from attack by insects or acarids.

Abstract: Compounds having the formula (I) ##STR1## [wherein: R.sup.1 and R.sup.2 are each alkyl or halogen, or they are trimethylene or tetramethylene; R.sup.3 is hydrogen or alkyl; A is alkylene; and R.sup.4 is optionally substituted phenyloxy or benzyloxy substituted with at least one alkyl, halogen, alkoxy, alkylthio, alkenyl, trifluoromethyl or nitro; optionally substituted phenyl substituted with one or two halogen atoms, alkyl or alkoxy; furyl or thienyl] and their salts.

Abstract: Mono- and di-thiophosphate esters having an isoxazolinone system attached at its 2-position through an optionally alkyl- or phenyl-substituted methylene or ethylene group to the sulphur or to one of the sulphur atoms are useful as insecticides and/or acaricides.

Abstract: A new ester of chrysanthemic acid having the formula ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are the same or different and each represents a hydrogen atom, a lower alkyl group or a halogen atom which exhibits insecticidal activity. The ester is prepared by reacting a 2,3-dihydro-3-benzofuranol derivative having the formula ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 are the same as above with chrysanthemic acid or an active ester thereof such as the halogenide and the anhydride.

Abstract: New organic phosphorus compounds having the formula ##STR1## wherein R.sub.1 represents an alkyl group of 1-4 carbon atoms, R.sub.2 represents an alkoxy group of 1-4 carbon atoms or phenyl group and R.sub.3 represents hydrogen atom, an alkyl group of 1-4 carbon atoms, phenyl group or the group of the formula -X-R.sub.4 in which R.sub.4 represents an alkyl group of 1-6 carbon atoms or a benzyl group which may be substituted with a halogen atom in the phenyl moiety and X represents oxygen atom or sulfur atom. The present compounds are prepared by reacting a phosphoric or phosphonic acid halide having the formula ##STR2## wherein R.sub.1 and R.sub.2 are as defined above and Y represents a halogen atom with a pyridazinone derivative having the formula ##STR3## wherein R.sub.3 is as defined above. The present compounds show a superior insecticidal activity against various harmful insects, e.g.