Please select the most similar patent number from A, B, C and D. Which number is?
Disclosed in the present invention are an avermectin B2a ethylenic derivative, and a preparation method therefor and the use thereof. The structural formula of the avermectin B2a ethylenic derivative is as represented by formula I. The compound has an efficient pesticidal activity against a plurality of targets, and in particular has a pesticidal activity against Spodoptera exigua, diamondback moths, Plutella xylostella, root knot nematodes and the like for crops.
A: Provided are a preparation and use of pyrrole and dihydropyrrole fused ring compound having insecticidal activity. Particularly, the present invention relates to a compound as represented by general formula (A) or the optical isomer, cis-trans isomer or pesticidally acceptable salt of the compound, and a preparation method thereof. The present invention also relates to an agricultural composition comprising the compound, the optical isomer, the cis-trans isomer or the pesticidally acceptable salt, and a use of the agricultural composition. The compound and the derivatives thereof have high insecticidal activity for homoptera and lepidoptera agricultural and forestry pests such as aphid, plant hopper, whitefly, leafhopper, thrips, cotton bollworm, cabbage worm, cabbage moth, prodenia litura and armyworm and the like.
B: The present invention relates to the technical field of agricultural chemicals and preparation. Specifically, disclosed is a purification method for 4&#34;-(s)-methylamino abamectin B2a benzoate. The purification method comprises the following steps: adding a crude product of methylamino abamectin B2a/2b benzoate to methyl tert-butyl ether, heating and dissolving, dropwise adding a mixed solution of tert-butanol and n-butyl ether, cooling and filtering after the dropwise adding, and cooling and crystallizing an obtained filtrate to obtain a product of 4&#34;-(s)-methylamino abamectin B2a benzoate. According to the purification method provided by the present invention, by selecting the mixed solution of methyl tert-butyl ether, tert-butanol and n-butyl ether as a crystallization solvent, and in coordination with twice cooling and crystallization, the product of 4&#34;-(s)-methylamino abamectin B2a benzoate having S-configured methylamino at bit 4&#34; and having a content of 98% or more is obtained, thereby facilitating improvement of the insecticidal activity of related preparations, and achieving a wide application prospect.
C: Disclosed in the present invention are the preparation method and use of a compound of 2,5-disubstituted-3-nitroimino-1,2,4-triazoline and its precursor nitroideneamino-guanidine compound. Their structural formulae are shown as formulae I and VI, wherein R1 is a saturated or unsaturated C1-C10 aliphatic alkyl, saturated or unsaturated C1-C10 fluorine substituted aliphatic alkyl, substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted thiazole, substituted or unsubstituted pyrazolyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted isoxazolyl, or tetrahydrofuran; R2 is a hydrogen, saturated or unsaturated C1-C10 aliphatic alkyl, substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted furyl, substituted or unsubstituted naphthyl. Tests on pesticidal activity demonstrate that compounds of formulae (I) and (VI) have a very high prevention effect against crop pests, such as aphids, plant hoppers, tetranychid mites, cotton bollworm and beet armyworm, etc., and can therefore be used as a plant pesticide.
D: The present invention provides a kind of nitroguanidine compounds, its preparation method and uses. The structure of the compound is as follows of formular I, in which R 1  is saturated or unsaturated C 1-10  aliphatic alkyl, benzyl or substituted benzyl, halogenated picolyl, halogenated thiazylmethyl, tetrahydrofuryl methyl or oxazolyl methyl; R 2  is hydrogen, saturated or unsaturated C 1-5  aliphatic alkyl, phenyl or substituted phenyl, pyridyl or substituted pyridyl; R 3 
   is hydrogen, saturated or unsaturated C 1-10  aliphatic alkyl, furyl, phenyl or substituted phenyl, benzyl or substituted benzyl. It testifies in the experiment of the insecticidal activity that the nitroguanidine compounds of formular I have good control efficiency to the crop pests of aphides and striatellus and cotton bollworm and asparagus caterpillar and so on, and that the compounds can be used as botanical insecticides.
Answer: B