Use of chromene or chromane derivatives as herbicidal agents

Abstract

The present invention relates to the field of herbicides useful for controlling the proliferation of unwanted plants. In particular, the invention relates to the use of at least one compound derived from chromene or chromane as a herbicidal agent, to a phytotoxic composition comprising said compound, and to a method for treating and / or controlling plants using such a compound. Figure to be published: none

Description

Description Title of the invention: Use of chromene or chromane derivatives as herbicidal agents

[0001] — The present invention applies to the field of herbicides useful for controlling the proliferation of unwanted plants. In particular, the invention relates to the use of at least one compound derived from chromene or chromane as that herbicidal agent, with a phytotoxic composition comprising said compound, thus that to a plant treatment and / or control process implementing such compound.

[0002] — Weeds are considered one of the scourges that cause the most losses in global agricultural production, which is responsible for more than 30% of the decline in yields and crop quality. These appear throughout the crop growth period and are particularly harmful at the time of sowing and during harvest. Over the past 60 years, the control of Weed control has been achieved almost exclusively through the application of herbicides. of unnatural origin, against which these weeds have developed a re- increasing resistance. For example, more than 50 species of "weeds" have a proven resistance to glyphosate, a widely used broad-spectrum systemic herbicide for agricultural and non-agricultural uses, are currently confirmed according to the database international data “Herbicide-Resistant Weed Database”, called the “super” weeds.

[0003] — Research teams have therefore focused on solutions and al- sustainable alternatives, particularly those derived from natural substances.

[0004] — Among the new synthetic molecules inspired by natural substances, we can cite the triketones (mesotrione, topramezone, tembotrione) based on lepto- spermone isolated from the plant Callistemon citrinus or bottlebrush, which would inhibit the enzyme p-hydroxyphenylpyruvate dioxygenase; cinmethyline based on isocineole, a terpene found in cardamom or certain varieties of pepper, which would inhibit tyrosine aminotransferase; and cantharidin-based endothalamium, a powerful defense toxin produced by insects, which would inhibit protein- phosphatases in plants. In particular, leptospermone was discovered at the end in the 1970s after observing that bottle brushing inhibited growth other plants in its environment, signaling the presence of a substance with allelopathic properties.

[0005] The literature has also proposed natural substances such as glu- Fosinate, also known as phosphinothricin and often sold under An ammonium salt form, derived from the degradation of bialaphos (or bilanaphos), a tripeptide isolated from bacteria. However, this product was withdrawn from the market in 2017 due to its classification as a potentially reprotoxic chemical. Other natural substances, such as fatty acids, have been marketed as biopesticides (e.g., pelargonic acid, marketed under the name Beloukha® agent, or acetic acid), acting as surface defoliants. Consequently, their activity is limited over time. Other research teams have focused on synthetic molecules based on chromene or chromane. In particular, USS053071 describes broad-spectrum herbicides comprising a chromane motif corresponding to one of the following formulas: [Chem.1] * db Pr TT As, Fan #4 / x NN { To oo 20 Yes {4 A. A 0 N o° ; += Î 4 GS, 75 FN TS0 .Ù 50 7e «Su os 170 9° «S0 Fa iPhe_ 7 ne pm ti ges LA LA “ { y A Fe TS $ T Spy el (°S PE LA, LA. ou (A 7 + NET Fer Ne ci ee el Some compounds in US5053071 include stereoisomers, which can pose challenges in terms of synthesis strategy, purification, and characterization of biological activity. Furthermore, the synthetic route from a phenolic core involves numerous steps using conditions difficult to implement on a large scale (allylation of a complex phenol, high-temperature Claisen rearrangement, hydroboration, cyclization, and then functionalization). International application WO2019 / 005484 describes herbicides comprising a chromene motif corresponding to the following formula: [Chem.2] Fa ee 55 NTSC A5 SF On 2 RS, CH { ST RAS However, some compounds in WO2019 / 005484 possess asymmetric centers, leading to enantiomers, diastereomers, and / or atropoisomers, which can pose problems in terms of synthesis strategy, purification, and especially the characterization of biological activity. Their synthetic pathways are not precisely described. There is therefore a need for new herbicide agents that are effective against unwanted plants, easy to prepare, and whose side effects on the environment are significantly reduced in contrast to those mentioned above. Thus, the aim of the present invention is to overcome the disadvantages of the aforementioned prior art and to provide a herbicidal agent with good performance in terms of herbicidal activity and / or selectivity, easy to prepare, and having reduced toxicity. The goal of the invention is achieved by the chromene and chromane derivative compounds which will be described below. The present invention thus has as its first object the use of at least one compound chosen from a compound corresponding to formula (I), one of its isomers, one of their organic and inorganic salts, as a herbicidal agent, said formula (I) having the following structure: [Chem.3] R° r° Rod s2 "| ST 2 î tr BE 8 F0 > 1 ( in which: * R', R7, and R° represent, independently of each other, a hydrogen atom, a halogen atom, a C, Cs alkyl or cycloalkyl radical, or a group selected from -OH, -COOH, -COORS, -ORS, and -SO>RS, with R° being a C, Cs alkyl or cycloalkyl radical, said C, Cs alkyl or cycloalkyl radical; which may be substituted by one or more substituents selected from a halogen atom and a hydroxyl group, * X is part of a six-membered heterocycle and represents an oxygen atom, a sulfur atom, a divalent group SO, a divalent group SO, and a divalent group NRS, with RS being a hydrogen atom, an alkyl or cycloalkyl radical in C, to Cs, or an aryl or heteroaryl radical in C; to C;, *1st symbol = represents a single or double bond at position 2,3 or 3,4 of the six-membered heterocycle bearing the heteroatom or divalent group X, such that said six-membered heterocycle comprises either two single bonds at positions 2,3 and 3,4, or a single bond at position 2,3 and a double bond at position 3,4, or a double bond at position 2,3 and a single bond at position 3,4, * L represents a bonding arm selected from linear and branched alkylene chains having at least one carbon atom, said linear or branched alkylene chains being able to be interrupted and / or terminated by one or more heteroatoms selected from an oxygen, sulfur, and substituted nitrogen atom, * Ar represents an aromatic group selected from the following groups: phenyl, naphthyl, furyl, thiophenyl, pyrrolyl, pyridinyl, indolyl, isoindolyl, benzofuryl, benzothiophenyl, quinolyl, isoquinolyl, imidazolyl, oxazolyl, thiazolyl, pyrimidyl, pyridazyl, pyrazyl, pyrrazolyl, and triazolyl, said aromatic group being substituted by one or more substituents selected from a halogen atom, a C, C, or Cs alkyl or cycloalkyl radical, an -OH group, a -COOH group, a -COOR7 group, an -ORT group, and a -SOR group”, with R' being a C, C, or Cs alkyl or cycloalkyl radical, said C, C, or C alkyl or cycloalkyl radical; being substituted by one or more substituents selected from a halogen atom and a hydroxyl group, * is an integer from 4 to 6 and represents the number of R* substituents, identical or different, present on the six-membered heterocycle, and * R* represents a hydrogen atom, a halogen atom, an alkyl or cycloalkyl radical in C, to C, or a group selected from -OH, -COOH, -COORS, -ORS and -SO; RS, with RS being an alkyl or cycloalkyl radical in C, to C, said alkyl or cycloalkyl radical in C, to Cs being able to be substituted by one or more substituents selected from a halogen atom and a hydroxyl group. The compounds (I) of the invention are derivatives based on chromene (2H-chromene or 4H-chromene) or chromane (3,4-Dihydro-2H-1-benzopyran), including compounds occurring naturally in liverworts, mosses found particularly in forests and wetlands, and compounds inspired by such naturally occurring liverwort compounds. The inventors have thus discovered that such compounds, according to the first object of the invention, exhibit significant herbicidal activity. Furthermore, these compounds are easy to prepare, and some can be extracted directly from the natural environment. For the purposes of the present invention, the term "herbicidal agent" means a product chemical in the form of an active substance or a phytosanitary composition effective in controlling the proliferation of unwanted plants. A herbicide can be described as total if it destroys all types of plants, or as selective if it kills only one or more categories of unwanted plants. Similarly, it can be classified by its mode of action, for example, root penetration, systemic action, or post-emergence action. A "root-penetrating herbicide" is a herbicide that acts by being absorbed through the roots of the plant, whereas a "foliar herbicide" is absorbed by the plant through the leaves. A "systemic herbicide" works by spreading throughout the plant via the sap, as opposed to a "contact herbicide" which only destroys the surfaces on which it is applied and is therefore in contact. Finally, a "post-emergence herbicide agent" acts on the plant after the emergence of the first seedlings, while a "pre-emergence herbicide agent" allows action to be taken as soon as they germinate. In the present invention, "isomers" means steric and optical structural isomers, said isomers having the same molar mass as the compound of formula (I), and the structural variations being limited to: - the position of X on the six-link heterocycle, - the position of the tetrahedral carbon when the six-membered heterocycle includes a double bond, - the position of the R!, R°, R°, and L-Ar groups on the phenyl group, and - the position of the n groups R* on the six-link heterocycle. Examples of inorganic salts of the compound of formula (I) and its isomers include the alkali and alkaline earth salts of the compound of formula (I) and its isomers. Examples of organic salts of the compound of formula (I) and its isomers include the ammonium salts of the compound of formula (I) and its isomers. In the present invention the alkyl or cycloalkyl radical in C, to Cs can be linear or branched, and it is preferably linear. In the context of the present invention, a halogen is chosen from F, Cl, Br and I, and particularly preferably from F and Cl. Defliniu 24 The alkyl or cycloalkyl radical as RS group is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical at C, to C3. The aryl radical as the RS group is preferably an aryl radical in Cs to Ce, and particularly preferably a phenyl radical. The heteroaryl radical as an RS group can be an indole or triazole radical. D as an aryl or heteroaryl radical at C; to C; is preferably an aryl radical at Cs to C5 The RS group is preferably a hydrogen atom or an alkyl or cycloalkyl radical. According to a particularly preferred embodiment of the invention, X represents an oxygen atom. Definition of R!, R2, and R* and R5 The alkyl or cycloalkyl radical as group R!, R°, or R* is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical in C, to C,. The alkyl or cycloalkyl radical as RS group is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical at C, to C3. The said alkyl or cycloalkyl radical as group R', R°, R°, or R° can be substituted by one or more substituents chosen from a halogen atom and a hydroxyl group. According to a particularly preferred embodiment of the invention, at least one of the groups R!, R°, and R° represents an -OH group, and advantageously the group R* represents an -OH group. This makes it easier to obtain the compounds of the invention and increases herbicidal activity. In this embodiment, the other two groups R! and R?, or R' and R3, or R? and R3, and advantageously the other two groups R! and R?, represent, independently of each other, a hydrogen atom, a -COOH group, or a -COORS group, with R5 being an alkyl radical in C, to C, and preferably a methyl radical. In a particularly preferred manner, still in this embodiment, the group R! represents a hydrogen atom or a -COOH group, and more particularly preferredly a hydrogen atom. In a particularly preferred manner, still in this embodiment, the group R? represents a hydrogen atom, a COOH group, or a -COORS group, with R5 being an alkyl radical in C, to Cs, and preferably a methyl radical, and more particularly preferred a hydrogen atom or a -COOH group. The six-chai heterocycle Said six-membered heterocycle bearing the heteroatom or divalent group X preferably comprises either two single bonds at positions 2,3 and 3,4, or one single bond at position 2,3 and one double bond at position 3,4, and particularly preferably one single bond at position 2,3 and one double bond at position 3,4. Definition of L L preferably represents a linear or branched alkylene chain having from | to 6 carbon atoms, particularly preferably a linear alkylene chain having from 2 to 3 carbon atoms, and more particularly preferably a linear alkylene chain having 2 carbon atoms. The linear or branched alkylene chain as the L-linking arm can be interrupted and / or terminated by one or more heteroatoms chosen from an oxygen, sulfur, and substituted nitrogen atom, and preferably by one or more oxygen atoms. Nitrogen can be substituted by an alkyl group at C5, preferably at C3, said alkyl radical being preferably a linear alkyl radical. Definition of Ar The alkyl or cycloalkyl radical as a substituent of the Ar group is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical at C, to C3. The alkyl or cycloalkyl radical as group R7 is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical in C, to C3. The said alkyl or cycloalkyl radical as a substituent of the Ar group or R group can be substituted by one or more substituents chosen from a halogen atom and a hydroxyl group. Ar preferably represents a phenyl group, said phenyl group being able to be substituted by one or more substituents as defined in the invention for the aromatic group Ar. Among the substituents of the aromatic group Ar, the -OH group is preferred. The six-membered heterocycle bearing the divalent group or heteroatom X comprises at least 4 R* substituents and at most 6 R* substituents depending on the presence or absence of a double bond within said heterocycle. The alkyl or cycloalkyl radical as the R“ group is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical in C, at C;. The alkyl or cycloalkyl radical as RS group is preferably an alkyl radical, particularly preferably a linear alkyl radical, and more particularly preferably a linear alkyl radical in C; to C3. The said alkyl or cycloalkyl radical as group R* or R° can be substituted by one or more substituents chosen from a halogen atom and a hydroxyl group. According to a first variant, the heterocycle includes a double bond, the compound then corresponds to the following formula (Ia) or (Ib): [Chem.4] R° n° r* R* a É $ to z 2 + to} L 4th RR SS db Ar. | AR >, x pie 1 PR; RR n° œ RR (0) Ar “ue LÉ x pie 1 (la) (1b) in which: # Ar, L, R!, R?, R°, and X are as defined in the invention, and * R#, R, Ré, and R“, identical or different, represent a hydrogen atom or an alkyl or cycloalkyl radical in C, to Cs, said alkyl or cycloalkyl radical in C, to Cs being able to be substituted by one or more halogen atoms. According to a particularly preferred embodiment of this first variant, R# represents a C alkyl radical, with C possibly substituted by one or more halogen atoms, R represents a hydrogen atom or a C alkyl radical, with Cs possibly substituted by one or more halogen atoms, and R* and R# re- represent a hydrogen atom. R*# advantageously represents a C3 alkyl radical, possibly substituted by one or more halogen atoms, and even more advantageously a methyl radical. This thus improves herbicidal efficacy. When R® represents an alkyl radical in C, to C; possibly substituted by one or more halogen atoms, it is preferably an alkyl radical in C, to C; possibly substituted by one or more halogen atoms, and even more preferably a methyl radical. According to a second variant, the heterocycle does not include a double bond, and the compound then corresponds to the following formula (Ic): [Chem.5] r° 3 4 Ru Rue 2 R Ré RC R° | S ab R Ar. “ Æ pt 1 (THE) in which: * Ar, L, R!, R?, R°, and X are as defined in the invention, and * R#, R®, R%*, R*, R®, and R°*, whether identical or different, represent a hydrogen atom or an alkyl or cycloalkyl radical in C, to Cs, said alkyl or cycloalkyl radical in C, to Cs being able to be substituted by one or more halogen atoms. According to a particularly preferred embodiment of this second variant, R# and R® represent a methyl radical, and R#, R#, R“, and R# represent a hydrogen atom. According to a preferred embodiment of the invention, the compound of formula (I) is chosen from the following compounds: [Table 1] Name Expanded Formula Compound Ial [Chem 6] OH Î Fe | S1S CH s A0 Sc, Cv Compound Ia2 [Chem 7] oH f 7° | STS | | NS A 0H Æ |Compound Ta3 [Chem 8] sTE SS î S / e OH Æ | Composed Tel [Chem 9] oh f 4 | S CH 3 ( = # 07 XcH, A Due to their herbicidal biological activity, the compounds as defined in the first object of the invention are useful in the fields of agriculture, gardening, and transportation, particularly for weed control on tarmacs or railway tracks. The compound as defined in the first object of the invention can be used in an isolated or non-isolated form, and / or in a natural or synthetic form. According to one embodiment, the compound as defined in the first object of the invention is implemented in an isolated form. According to the invention, the term "isolated form" describes the fact that the compound as defined in the first object of the invention is implemented in a pure form, that is to say, distinct from a mixture with other compounds, which may be, for example, a plant extract containing it in association with other substances. Thus, these compounds as defined in the first object of the invention can be isolated from plant extracts but can also be prepared synthetically, in particular as illustrated in the examples that follow. According to another embodiment, the compound as defined in the first object of the invention is implemented in the form of a natural extract, in particular of plant origin, the container. The natural origin makes it possible to consider a reduced environmental impact. In particular, certain compounds as defined in the first object of the invention can be implemented in the form of an extract from liverwort plants containing them, including, but not limited to: Radula laxiramea, Radula variabilis, Radula complanata, Radula buccinifera, Radula japonica, Radula oyamensis, Radula tokiensis, Radula perrottetii, Radula kojana, and Radula javanica, which may generally contain a mixture of these compounds as defined in the first object of the invention and other related compounds. The implementation may directly involve the plant itself, or any other biological agent enabling the production of the compounds of the invention, their drying, and their reduction to powder. For example, the compound (lal) was isolated from the plant Radula kojana [Asakawa et al, Phytochemistry, 1991, 30, 219-234]. The extract can be obtained by mechanical extraction, for example by pressing, or by chemical extraction, notably by leaching, maceration, or infusion. Where appropriate, the extraction can be followed by a purification step using chromatography or crystallization. According to yet another embodiment, the compound as defined in the first object of the invention can be generated in situ or just before use from a precursor, for example by hydrolysis, in particular of an ester. Of course, the various compounds as defined in the first object of the invention can be used in mixture as herbicidal active substances according to the invention. According to the invention, a "herbicidal agent" corresponds to any compound or composition having the property of killing so-called undesirable plants, in particular plants. These so-called undesirable plants are generally mosses, algae, or weeds, including but not limited to anthemis, amaranths, rock cress, mugwort, orache, cornflower, shepherd's purse, bromes, cardamines, thistle, goosefoot, couch grass, poppy, jimsonweed, spurge, fumitory, cleavers, galinsoga, geraniums, field gromwell, sow thistles, dead-nettles, toadstools, bindweed, chickweed, field mustard, forget-me-not, nettles, wood sorrel, pennyroyal, field pansy, dandelion, plantains, wild radish, ryegrass, buttercup, knotweeds, groundsel, field spurge, speedwells and common vetch. For example, so-called undesirable plants may be those listed in HYPPA (HYpermedia for Plant Protection - Adventices), an encyclopedic database developed by INRAe Dijon, containing data on 580 "weeds" of Western European crops. As can be seen from the examples below, the compounds as defined in the first object of the invention are particularly advantageous as post-emergence herbicide agents. They are particularly advantageous both as root-penetrating herbicides and as systemic herbicides. In particular, the compounds as defined in the first object of the invention are used as a herbicidal agent on plants at the seedling development stage, which is a young germinated plant with only a few leaves. The compounds as defined in the first object of the invention are used in a formulation suitable for their application to the area to be treated. Generally speaking, this formulation dedicated to the application is a liquid and usually aqueous formulation. This liquid formulation can be supplied as such to the user, i.e. ready to use. It can also be a concentrated liquid formulation that must be diluted by the user just before use. It can also be a formulation in solid form, such as granules, to be applied as such by the user or to be dispersed in an aqueous medium before use. In general, application in a diluted form is preferred, particularly in an aqueous environment. The compounds as defined in the first object of the invention can be implemented at a concentration ranging from 1 ug / mL to 200 pg / mL, preferably from 5 ug / mL to 150 pg / mL, and even more preferably from 10 ug / mL to 100 ug / mL in compound(s) as defined in the first object of the invention. Of course, this effective concentration is likely to vary depending on the chemical nature of the compounds as defined in the first object of the invention, the method of formulation, as well as the variety and stage of development of the unwanted plants to be treated. It is also advantageous that the formulation be suitable for spraying. When the compounds according to the invention are represented by formula (Ia) of the invention with R? = OH, X = O, R* = H, and R# = H (hereinafter referred to as (Ia')), they can be prepared by condensation reaction of an unsaturated α,β-aldehyde of formula (II) with a diphenol of formula (III) according to the step illustrated in the following diagram: [Chem.10] 9 oH OH ; R PS R< Æ Le AL = LUS GE a Spb LF Don A É =4 $ OH z} , A Dé a” ! H i IR 1) +0 - LL ÿ, Ars. AL 0 Su, COAST a da Nb ASF on a; RR}, R' R (H) (UD) (la") in the presence of an acid catalyst chosen from diammonium ethylene diacetate (EDDA), Lewis acids such as Yb(OTf);. ZnCl, and Brønsted acids such as NH₃, OAc, TFA, or AcOH; of a nonpolar aprotic solvent or an acidic solvent, in a closed reactor (e.g., sealed tube), under reflux, and in an inert atmosphere. The aprotic nonpolar solvent can be toluene, xylene, benzene, or dichloromethane. The acidic solvent can be acetic acid. The aldehyde of formula (IT), especially when not commercially available, can be obtained according to the three steps illustrated in the following diagram: [Chem.11] OEt Ï t \e to * to; Ï Bo SS % > a 2e + um nous | ere Ë Ps U 5 dE ® R pie” Near pe “a® ga (iv) {vw {ty the first step comprising the reaction of triethyl phosphonoacetate with a ketone of formula (IV) in the presence of a strong base such as NaH, potassium tert-butylate or sodium methylate, and a polar aprotic solvent such as tetra- hydrofuran, methyltetrahydrofuran, or toluene, to form compound (V); the second step comprising the reduction under an inert atmosphere of the ester function of compound (V) to an alcohol function in the presence of a reducing agent such as dii-sobutylaluminium hydride (DIBALH), lithium aluminium hydride, or lithium borohydride, to form compound (VI); and the third step comprising the oxidation under an inert atmosphere of the alcohol function of compound (VI) to the aldehyde function in the presence of an oxidant such as MnO, NaCl in the presence of TEMPO, or DMSO in the presence of oxalyl chloride or another electrophilic agent, to form compound (IT). The invention has as its second object a phytotoxic composition comprising, as an active herbicidal substance, at least one compound as defined in the first object of the invention, in combination with one or more formulation additives to improve solubility in water and / or penetration into plant tissues such as, for example, anionic, cationic, amphoteric, or non-ionic surfactants. The phytotoxic composition may also include one or more other active ingredients chosen from among fertilizers, growth regulators, and ancillary herbicidal agents. The expression "ancillary herbicide" according to the invention refers to a herbicide different from a compound as defined in the first object of the invention. It may indeed be advantageous to combine a compound as defined in the first object of the invention with an ancillary herbicide whose effectiveness can complement that of the compounds as defined in the first object of the invention. However, this ancillary herbicide is preferably a compound selected to have a lower environmental impact. The ancillary herbicides may be chosen from ammonium nonanoate, nonanoic acid (= pelargonic acid), intermediate chain length fatty acids (Le. in Cg-C;2), and their salts, urea derivatives, borax, copper sulfate, carboxylic acids (especially acetic acid) and their salts, nitrogen compounds, calcium salts, and mixtures thereof. The fertilizer is preferably a nitrogen fertilizer, which may be chosen from urea; ammonium salts; in particular ammonium chloride, ammonium nitrate or ammonium sulfate; ammonium and potassium phosphate; leather powder; bone meal, plant powder; and a mixture thereof. Growth regulators can be chosen from maleic hydrazide, chloromequat-chloride (e.g. Cyclocel®), auxin derivatives, natural growth regulators, and mixtures thereof. Advantageously, naturally occurring growth regulators include sa- acid licylic acid, salts of salicylic acid such as ammonium salicylate, jasmonates, auxins, gibberellins, cytokinins, lunularic acid, abscisic acid, or any mixture thereof. A composition according to the invention may also contain other more conventional ancillary additives such as surfactants, antifoaming agents, disintegrating agents, stabilizing agents, humectants, thickeners or pH regulators. The choice of these additives is most often made with regard to the form considered for the composition. The phytotoxic composition may include said compound (I) in its pure form or in the form of a plant extract or plant powder containing it. The phytotoxic composition according to the invention may be in the form of a solid composition, particularly in the form of a powder or granules suitable for aqueous dilution. The solid composition may also be dispersed directly onto the area to be weeded and dissolved by moistening. A phytotoxic composition according to the invention may also be in the form of a liquid composition, particularly in concentrated or ready-to-use form, notably as a solution or emulsion. Similarly, the concentrated liquid composition may be diluted before use by adding adjuvants where appropriate. The invention has as its third object a method for controlling the development and / or treating unwanted plants on the surface of a target area comprising bringing the target area into contact with an effective amount of a compound as defined in the first object of the invention, or at least a phytotoxic composition as defined in the second object of the invention. Preferably, the compound as defined in the first object of the invention is supplied to the plant via the growing substrate. This growing substrate can be soil but also the growing media considered for hydroponic cultivation. Advantageously, the compound is applied directly to the surface of the growing medium on which the plants to be treated develop. Advantageously, the contact is made by spraying at least one compound as defined in the first object of the invention or at least one composition as defined in the second object of the invention. Thanks to the compound as defined in the first object of the invention, the phytotoxic composition as defined in the second object of the invention, or the process as defined in the third object of the invention, the unwanted plant is killed in less than 96 hours, preferably in less than 48 hours, and even more preferably fully in less than 24 hours after application. Other features, variations and advantages of the use, phytotoxic composition, or process according to the invention will become clearer from reading the examples of embodiment that will follow, given by way of illustration and not limitation of the invention. EXAMPLES Toluene, acetonitrile, and benzene were distilled over calcium hydride before use and, if necessary, degassed by bubbling nitrogen gas. Analytical thin-layer chromatography (TLC) was performed on silica gel-on-aluminum plates (silica gel 60, F254, Merck) and visualized by exposure to ultraviolet light and / or exposure to a basic potassium permanganate solution or a p-anisaldehyde staining solution followed by heating. Flash column chromatography was performed on silica 60 (40-63 µm). Nuclear magnetic resonance (¹H NMR and ¹³C NMR) spectra were recorded at 25°C with a Bruker Avance 400 spectrometer (¹H NMR at 400 MHz, ¹²C NMR at 100 MHz) using CDCI as the reference solvent relative to residual CHCI (¹H = 7.26 ppm, ¹³C = 77.1 ppm). Chemical shifts are given in ppm and coupling constants (J) in Hertz. Data for the ¹H NMR spectra are reported as follows: chemical shift ppm (br s = large singlet, s = singlet, d = doublet, t = triplet, q = quadruplet, dd = doublet of doublets, td = triplet of doublets, ddd = doublet of doublets of doublets, m = multiplet, coupling constants, integration). High resolution mass spectra (HRMS) were obtained on a JEOL JMS-GCmate II spectrometer and are reported in m / z. Infrared spectra were recorded on a PerkinElmer FTIR spectrometer using the attenuated total reflectance (ATR) technique. Absorption maxima (Vu) are reported as wavenumbers (em). EXAMPLE 1: Synthesis of compound Ia1 Preparation of dihydropinosylvin of formula (IIIa1) Dihydropinosylvin was prepared according to the steps illustrated in the following diagram: [Chem.12] G oMe OMe I 07 ES D AT F0 —_ 2478 z* { J free Fu L À qe NSE ES om Le à Ÿ Fou { * z ï nf Bone OME { “es LA (7 ST GS om Lg ot To mA ÎÂA { The SF {Kat} 1.1 First step: Preparation of (E)-3.5-dimethoxystilbene The first step is a Horner-Wadsworth-Emmons reaction. Potassium tert-butylate (t-BuOK) (10.8 g, 96.3 mmol) and anhydrous tetrahydrofuran (THF) (120 mL) were added to a flame-dried 500 mL flask fitted with a magnetic stir bar under an inert atmosphere. The mixture was cooled in an ice bath, and then diethyl benzylphosphonate (20.6 mL, 90.3 mmol) was added dropwise over 30 minutes, followed by a portionwise addition of 3,5-Dimethoxybenzaldehyde (10.0 g, 60.2 mmol). The mixture was allowed to rise to room temperature and then stirred for 2 h. The THF was removed under vacuum, and then a mixture of water and methano (H:O:MeOH) (2:1, approximately 60 mL) was added until the product precipitated. Filtration and drying under vacuum yielded (E)-3,5-dimethoxystilbene as a white solid (13.5 g, 56.0 mmol, 93% yield). 'H NMR (400 MHz, CDCI): at = 7.53 — 7.49 (m, 2H), 7.39 — 7.33 (m, 2H), 7.29 — 7.23 (m, 1H), 7.09 (d, J = 16.3 Hz, 1H), 7.04 (d, J = 16.3 Hz, 1H), 6.69 — 6.66 (m, 2H), 6.40 (t, J = 2.3 Hz, 1H), 3.83 (s, 6H). The second step is a catalytic hydrogenation reaction of the double bond using ammonium formate. This avoids the use of hydrogen gas. To a flame-dried 500 mL flask, (E)-3,5-dimethoxystilbene as prepared in the previous step (14.0 g, 58.2 mmol) and 10% Pd / C (1.40 g, 10 wt%), followed by ethyl acetate (243 mL, 0.245 M), were added. Ammonium formate (18.4 g, 291 mmol) was then added, and the mixture was left to stir overnight at room temperature. The reaction mixture then it was filtered through a Celite buffer and evaporated under vacuum. The remaining ammonium formate was precipitated by the addition of dichloromethane, and the mixture was filtered again and then evaporated under vacuum to give the 1,3-Dimethoxy-5-phenethylbenzene expected as a light yellow oil (12.7 g, 52.4 mmol, yield 90%). ''H NMR (400 MHz, CDCI;): at = 7.32 — 7.25 (m, 2H), 7.23 — 7.17 (m, 3H), 6.36 — 6.30 (m, 3H), 3.76 (s, 6H), 2.95 — 2.82 (m, 4H). 1.3. Third step: Preparation of dihydropinosylvin The third step is the demethylation of phenols in an acidic aqueous medium. To a 250 ml flask equipped with a magnetic stir bar, the following was added: 1,3-Dimethoxy-5-phenethylbenzene as prepared in the previous step (2.03 g, 8.38 mmol) was followed by hydrobromic acid (HBr) (24.6 mL, 48 wt% in water) and glacial acetic acid (24.6 mL, HBr:AcOH 1:1 v / v, final concentration of 0.15 M). The reaction mixture was then heated under reflux for 4 h and allowed to cool to room temperature. The reaction mixture was diluted with water (50 mL) and extracted with diethyl ether (Et,O) (3 x 50 mL). The organic phase was treated with activated carbon, filtered, and reduced under vacuum to give dihydropinosylvin as a white solid (1.68 g, 7.86 mmol, 94%). 'H NMR (400 MHz, CDCI-): at = 7.33 — 7.25 (m, 2H), 7.24 — 7.15 (m, 3H), 6.31 — 6.18 (m, 3H), 4.71 (br s, 2H), 2.93 — 2.75 (m, 4H). Preparation of 2,2-Dimethyl-7-phenethyl-2H-chromen-5-ol (Compound Ia1): To a flame-dried, sealed tube fitted with a magnetic stir bar under an inert atmosphere, dihydropinosylvin obtained in the previous step (4.00 g, 18.7 mmol·¹eq.) was added, followed by anhydrous toluene (0.1 M) and 3-methyl-2-butenal (prenal) (1.5 equiv.). Ethylenediammonium diacetate (EDDA, ​​5 mol%) was then added. The container was sealed and heated to 115°C for 1 h. This procedure (addition of EDDA and heating) was repeated 3 times (totaling an addition of 15 mol% EDDA). After returning to room temperature, a small amount of silica was added, and the solvent was removed under vacuum. The crude mixture was purified by flash silica column chromatography (dry loading), with hexane / ethyl acetate elution to give the expected 2,2-dimethyl1-7-phenethyl-2H-chromen-5-ol (compound 6) as a viscous brown liquid (4.28 g, 15.3 mmol, yield 82%). 'H NMR (400 MHz, CDCIs): & = 7.31 — 7.24 (m, 2H), 7.22 — 7.15 (m, 3H), 6.58 (d, J = 10.0, 1H), 6.32 — 6.29 (m, 1H), 6.14 — 6.10 (m, 1H), 5.55 (d, J = 10.0, 1H), 4.59 (br s, 1H), 2.92 — 2.83 (m, 2H), 2.80 — 2.73 (m, 2H), 1.42 (s, 6H). EXAMPLE 2: Synthesis of compound Ia1 Preparation of 2-methyl-7-phenethyl-2H#-chromen-5-ol To a flame-dried, sealed tube fitted with a magnetic stir bar under an inert atmosphere, compound (IIIa1) as previously prepared in Example 1 (300 mg, 1.4 mmol, 1 equiv.) was added, followed by anhydrous toluene (0.1 M) and (2E)-but-2-enal (1.5 equiv.). Ethylene diammonium diacetate (EDDA, ​​5 mol%) was then added. The container was sealed and heated to 115°C for 1 h. This procedure (addition of EDDA and heating) was repeated three times (totaling an addition of 15 mol% EDDA). After the tube had cooled to room temperature, a small amount of silica was added, and the solvent was removed under vacuum. The crude mixture was purified by flash silica column chromatography (dry loading), with hexane / FtOAc elution to give the corresponding chromene (la2) as a viscous brown liquid (13 mg, 0.0488 mmol, yield 3%). 'H NMR (400 MHz, CDCIs): at = 7.32 — 7.13 (m, SH), 6.65 (d, J = 9.8, 1H), 6.33 — 6.28 (m, 1H), 6.15 - 6.08 (m, 1H), 5.58 (d, J = 9.8, 1H), 5.02 — 4.88 (m, 2H), 2.95 — 2.69 (m, 4H), 1.43 (d, J = 6.8, 3H). EXAMPLE 3: Synthesis of compound Ia3 Preparation of the aldehyde with the formula (ITa3) The aldehyde with formula (IIa3) was prepared according to the steps illustrated in the following diagram: [Chem.13] o OH LA 4 qe Ë 9 Ï Î | a 8 Ï = , 2 ; + À Gitg eee AO j perse ù + % .s no <<" Cour S 06 Frac Le vue me De” 36 1 {IVa3) (va3) {Vta3) {ila3) In a flame-dried, round-bottom flask fitted with a magnetic stir bar under an argon atmosphere, NaH₂O (dispersion in 60% mineral oil, 1.4 equiv.) and anhydrous THF (final concentration: 0.26 M) were added. The resulting suspension was cooled to 0°C, and then triethyl phosphonoacetate (1.5 equiv.) was added dropwise using a syringe over 30 minutes, followed by butanone (IVa3) (1.25 mL, 13.9 mmol, 1 equiv.). The mixture was allowed to warm to room temperature and stirred overnight, and then the reaction was stopped with a saturated aqueous solution of NH₄Cl.The aqueous phase was extracted three times with Et,O and the combined organic phases were dried over magnesium sulfate (MgSO4), evaporated under vacuum and purified by column chromatography, with CH,Cl as the eluent, to give the compound (Va3) (E / Z)-3-Ethyl 2-Methylpent-enoate as a viscous yellow liquid (E / Z = 78:22, 1.94 g, 13.6 mmol, yield). 98%). Isomer E: ¹H NMR (400 MHz, CDCI): α = 5.67–5.65 (m, 1H), 4.15 (q, J = 7.2 Hz, 2H), 2.21–2.12 (m, SH, H⁴), 1.28 (t, J = 7.2 Hz, 3H), 1.07 (t, J = 7.5 Hz, 3H). 3.2 Second step: Preparation of (E / Z)-3-Methylpent-2-en-1-O₂ In a flame-dried, round-bottom flask fitted with a magnetic stir bar under an inert atmosphere, the compound (Va3) obtained in the previous step (3.88 g, 27.3 mmol, 1 equiv.) was added, followed by dry CHCl₂ (final concentration: 1.12 M). The solution was cooled to 0°C, then DIBALH (1 M in CHCl₂, 2.1 equiv.) was added using a syringe, and the mixture was stirred for 2 h. The reaction was stopped by adding MeOH (2.5 equiv.) at 0°C and allowed to cool to room temperature. A saturated NaCl solution was then added, followed by Et₂O, and the mixture was filtered through Celite. The phases were separated, and the organic phases were dried over MgSO₄ and concentrated under vacuum. The crude mixture was purified by flash column chromatography with a mixture of Et,O:CH:CL, (5% Et,O:CH:CIz) as the eluent, to yield the compound (VIa3) (E / Z)-3-Methylpent-2-en-1-ol as a colorless liquid (E / Z = 78:22, 1.39 g, 13.9 mmol, yield 51%). F isomer: 'H NMR (400 MHz, CDCIa): at = 5.44 — 5.35 (m, 1H), 4.20 — 4.10 (m, 2H), 2.14 — 2.00 (m, 2H), 1.76 — 1.66 (m, 3H), 1.05 — 0.98 (m, 3H). To a flame-dried round-bottom flask fitted with a magnetic stir bar under an inert atmosphere, MnO₂ (5 equiv.) and anhydrous CH₃Cl₂ (0.49 M) were added, followed by the compound (Vla3) obtained in the previous step (930 mg, 9.29 mmol, 1 equiv.). A condenser was connected, and the mixture was heated under reflux overnight. The mixture was then allowed to cool to room temperature and filtered through Celite buffer. The solvent was removed under vacuum, and the crude mixture was purified by flash column chromatography with a CH₃Cl / pentane (1:1) mixture as the eluent, yielding the compound (IIa3) (E / Z)-3-Methylpent-2-enal as a colorless liquid (E / Z = 78:22, 400 mg, 13.9 mmol, yield 44%). EF isomer: 'H NMR (400 MHz, CDCIa): & = 9.97 (d, J = 8.2, 1H, H-1), 5.86 — 5.81 (m, 1H, H-2), 2.60 (q, J = 7.5, 2H, H-3), 1.98 (d, J = 1.3, 3H, H-4), 1.17 (t,J = 7.6, 3H, H-5). Preparation of 2-ethyl-2-methyl-7-phenethyl-2#-chromen-5-ol (Compound Ia3): To a flame-dried, sealed tube fitted with a magnetic stir bar under an inert atmosphere, compound (IIIa) as previously prepared in Example 1 (50 mg, 0.233 mmol, 1 equiv.) was added, followed by anhydrous toluene (0.1 M) and aldehyde (IIa3) as previously prepared in Example 3 (1.5 equiv.). Ethylene diammonium diacetate (EDDA, ​​5 mol%) was then added. The container was sealed and heated at 115°C for 1 h. This procedure (addition of EDDA and heating) was repeated 3 times. (totaling an addition of 15 mol% of EDDA), then after returning to room temperature a small amount of silica was added and the solvent removed under vacuum. The crude mixture was purified by flash silica column chromatography (dry loading), with hexane / EtOAc elution (95:5, R; = 0.28) to give the corresponding chromene (Ia3) as a yellow viscous liquid (27 mg, 0.0017 mmol, 39%). 'H NMR (400 MHz, CDCI;): at = 7.30 — 7.24 (m, 2H), 7.22 — 7.14 (m, 3H), 6.26 (d, J = 10.1, 1H), 6.30 — 6.27 (m, 1H), 6.11 — 6.08 (m, 1H), 5.49 (d, J = 10.1, 1H), 4.85 — 4.68 (br s, 1H), 2.90 — 2.81 (m, 2H), 2.80 — 2.71 (m, 2H), 1.79 — 1.62 (m, 2H), 1.36 (s, 3H), 0.95 (t, J = 7.5, 3H). NMR *C (101 MHz, CDCI;): at = 154.2, 151.1, 143.5, 141.7, 128.4, 128.3, 127.4, 125.9, 116.9, 109.1, 107.7, 107.3, 78.6, 37.9, 37.4, 33.7, 25.8, 8.2. IR(ATR): 3404, 2972, 2929, 2869, 1623, 1576, 1496, 1434, 1136, 1062, 829. HRMS (ESI+): Calculation for ChH»:0>+ [MH#]: 295.1693; Obtained: 295.1686. EXAMPLE 4: Synthesis of compound Ic1 To a flame-dried, sealed tube fitted with a magnetic stir bar under an inert atmosphere, compound (Ia1) (100 mg, 0.36 mmol) and 10% Pd / C (10 mg, 10 wt%), followed by ethyl acetate (1.52 mL, 0.245 M), were added. Ammonium formate (115 mg, 1.82 mmol) was then added, and the mixture was left to stir overnight at room temperature. Subsequently, 10 wt% Pd / C (10 mg) and ammonium formate (68.09 mg, 1.08 mmol) were added again. The reaction mixture was left to stir for 3 h, then filtered through Celite buffer and evaporated under vacuum. The remaining ammonium formate was precipitated by adding dichloromethane and the mixture was filtered again and then evaporated under vacuum to give the expected compound (Ic1) as a pale yellow liquid (97.2 mg, 0.34 mmol, yield 97%). "H NMR (400 MHz, CDCI;): at = 7.32 — 7.24 (m, 2H), 7.22 — 7.14 (m, 2H), 6.33 (d, 1H), 6.19 (d, 1H), 4.63 — 4.59 (br s, 1H), 2.92 — 2.70 (m, 2H), 2.63 (t, 1H), 1.81 (t, 1H), 1.33 (s, 6H). EXAMPLE 5 of the use of compounds (Ia1), (Ia2), (Ia3) and (Ic1) as herbicidal agents Biological tests were performed under axenic conditions on Arabidopsis thaliana ecotype Col-0 seedlings grown hydroponically at the cotyledon stage. Sterilized seeds were sown in microplates (10 seeds per well containing 200 µL of distilled water) and cultured for 10–13 days at 22°C under a 16h / 8h (day / night) photoperiod. Treatment was carried out by replacing the culture medium with an equivalent volume of water containing the molecule to be tested dissolved in DMSO. The concentration of the molecule to be tested was 110 µg / ml. The DMSO concentration The maximum concentration within the treated wells was 1% by volume. A control was therefore implemented to monitor for the presence of DMSO at this concentration. The phytotoxicity of the treatment was assessed after 48 hours of culture by visual analysis of the induced chlorosis. The results are given in Table 2 below. The manifestation of herbicidal activity is indicated by A for Active in the case where the plant is killed, that is to say when both cotyledons have lost all of their green colour, 48 h after application of the product. The absence of herbicidal activity is indicated by "N" for Not active, in cases where no biological activity is observed. [Tables 2] Name Formula developed Activity after 48h Compound Ial | |[Chem 14] |A oH t 4 ( SS CH, OC fe CH, LA Compound Ia2 |[Chem 15] |A OH T 4 (NS | = Pan P |Compound Ia3 |[Chem 16] |A | SYS A [Compound |[Chem 17] |A Oh 4 | 5 CH 3 ( S a? 07 cH, Æ

Claims

Demands

1. Use of at least one compound selected from a compound meeting to formula (I), one of its isomers, and one of their organic and in- organic, and, as a herbicidal agent, said formula (I) having the following structure: [Chem.18] R° rÊ 2 4 R__ 19 5 XOSNTS Tu Ar. | Jr h N70 # / x 2; ; ( in which: * R!, R°, and R° represent, independently of each other, a hydrogen atom, halogen atom, alkyl radical or cy- cloalkyl at C, C5, or a group selected from -OH, -COOH, -COORS, -OR° and -SO;R°, with R° being an alkyl or cycloalkyl radical at C, at C s, said alkyl or cycloalkyl radical in C, with Cs being able to be substituted by one or more substituents chosen from a halogen atom and a hydroxyl group, * X is part of a six-membered heterocycle and represents an atom oxygen, a sulfur atom, a divalent group SO, a group divalent SO,, and a divalent group NRS, with RS being an atom hydrogen, an alkyl or cycloalkyl radical in C, Cs, or a radical aryl or heteroaryl in C; at Ca, *The symbol == represents a single or double bond in position 2, 3 or 3, 4 of the six-link heterocycle carrying the heteroatom or the divalent group X, so that said heterocycle has six links comprise either two simple links in positions 2,3 and 3,4, either a simple bond in position 2,3 and a double bond in position 3,4, i.e., a double bond in position 2,3 and a single bond in position 3,4, * L represents a linking arm chosen from among the alkylene chains linear and branched having at least one carbon atom, said linear or branched alkylene chains that can be interrupted and / or terminated by one or more heteroatoms chosen from an atom of oxygen, sulfur, and substituted nitrogen, * Ar represents an aromatic group chosen from among the phenyl groups, naphthyl, furyl, thiophenyl, pyrrolyl, pyridinyl, indolyl, isoindolyl, benzofuryl, benzothiophenyl, quinolyl, isoquinolyl, imidazolyl, oxazolyl, thiazolyl, pyrimidyl, pyridazyl, pyrazyl, pyrrazolyl and triazolyl, said aromatic group being substituted by one or more substituents chosen from a halogen atom, a alkyl or cycloalkyl radical in C, Cs, an -OH group, a - group COOH, a group -COOR?, a group -OR”, and a group -SO4R7, with R” being an alkyl or cycloalkyl radical at C, to C5, said alkyl radical or cycloalkyl in C, to C; which can be substituted by one or more sub- constituents chosen from a halogen atom and a hydroxyl group, * is an integer from 4 to 6 and represents the number of sub- constituents R*, identical or different, present on the six-membered heterocycle links, and *R* represents a hydrogen atom, a halogen atom, a radical alkyl or cycloalkyl at C, to C5, or a group selected from -OH, COOH, -COORS, -OR° and -SOÎRS, with RS being an alkyl or cy- radical cloalkyl at C, to C, said alkyl radical or cycloalkyl at C, to C5 which can be substituted by one or more substitutes chosen from a halogen atom and a hydroxyl group.

2. Use according to claim |, characterized in that X represents an oxygen atom.

3. Use according to claim 1 or 2, characterized in that at least One of the groups R!, R?, and R° represents a -OH group.

4. Use according to any one of the preceding claims, ca- characterized in that the R° group represents an -OH group, and the two other groups R' and R? represent, independently of each other, a hydrogen atom, a -COOH group, or a -COORS group, with R° being an alkyl radical in C, to Cs.

5. Use according to any one of the preceding claims, ca- characterized in that L represents a linear alkylene chain having 1 with 6 carbon atoms.

6. Use according to any one of the preceding claims, ca- characterized in that Ar represents a phenyl group, said group phenyl can be substituted by one or more substituents such as defined in claim 1.

7. Use according to any one of the preceding claims, ca- characterized in that the heterocycle includes a double bond, the composed of formula (I) then corresponds to the following formula (la) or (Ib): [Chem.19] R° n° r* pis i 4 7 + 2 by R' R STS | re Ar su Æ x d 1 + a 2 À Ÿ R? 4c RR (0) Ar. se Æ x pie 4 (la) (Ib) in which: * Ar, L, R!, R?, R°, and X are such that defined at any one of the re- demands | at 6, and * R#, R*%, R“, and R#, whether identical or different, represent an atom hydrogen or an alkyl or cycloalkyl radical at C, to C5, said radical alkyl or cycloalkyl in C, to Cs that can be substituted by one or several halogen atoms.

8. Use according to claim 7, characterized in that R“ represents an alkyl radical at C, to C, possibly substituted by one or more halogen atoms, R represents a hydrogen atom or a radical alkyl group at C, at C; possibly substituted by one or more atoms of halogen, and R* and R% represent a hydrogen atom.

9. Use according to any one of claims 1 to 6, characterized in that the heterocycle does not contain a double bond, the compound formula (I) then corresponds to the following formula (Ic): [Chem.20] R° 3 44 2 Fat ge & R R- | ss gp Ar ss Æ pe 1 in which: * Ar, L, R!, R?, R°, and X are such that defined at any one of the re- demands | at 6, and * R#, R#, D, R#, R4e, and R*#, whether identical or different, represent a hydrogen atom or an alkyl or cycloalkyl radical in C, to C, said alkyl or cycloalkyl radical in C, to C; which can be substituted by one or several halogen atoms.

10. Use according to claim 9, characterized in that R®# and R® re- present a methyl radical, and R*#, R*#, R*, and R*# represent a hydrogen atom.

11. | Use according to any one of the preceding claims, ca- characterized in that the compound of formula (I) is chosen from among the The following compounds: [Tables 3] Name Expanded Formula Compound Ial ([Chem 21] OH $ 4 CA CH3 | *% eo CH, Æ |Compo sé Ia2 [Chem 22] OH f re { SN = A ve A |Compo sé Ta3 [Chem 23] st { NN Î S Ze Hs LA |Compo sé Tel [Chem 24] OH { = | S CH, Se Æ 07H, Pa

12. Phytotoxic composition, characterized in that it comprises, as of herbicidal active substance, at least one compound as defined in any one of claims 1 to 11, in combination with one or several formulation additives to improve solubility in water and / or penetration into plant tissues.

13. Phytotoxic composition according to claim 12, characterized in that that it also includes one or more other assets chosen from fertilizers, growth regulators, and herbicides annexes.

14. | Method for controlling the development and / or treating inde- desirable surface features of a target area including contact with the target area with an effective amount of at least one compound such as defined in any one of claims 1 to 11 or at least one phytotoxic composition as defined in claim 12 or 13.