CH622407A5 - Pesticidal composition containing organostannic compounds - Google Patents

Description

The present invention relates to a pesticidal composition containing organotin derivatives of sucrose of general formula:

C00 sacch.

-I X

i eoo

/ _cH2_7n fs, _7m smAAi3

25 where sacch. represents a sucrose residue, X represents an orthophenylene, ethylene or vinylene radical, m represents 0 or 1, p represents 0 when m represents 1 and represents 1 when m represents 0, n represents 0 or an integer from 1 to 6, it being understood that, when m represents 1, n represents an integer from 1 to 6, and R1, R2 and R3, identical or different, represent radicals such that the tin atom is united to three carbon atoms, while that its fourth valence is not satisfied by a bond with a carbon atom. Thus, when n represents 0, that p represents 1 and that m represents 0, or when p represents 0, that m represents 1 and that n represents an integer, the symbols R1, R2 and R3 all represent organic radicals, identical or different, such that the tin atom forms three bonds with carbon atoms of these radicals R1, R2 and R3. However, when n represents an integer, that m represents 0 and that p represents 1, two of the symbols R1, R2 and R3 represent organic radicals as above and the third of these symbols represents an inorganic radical or an organic radical, to which case this organic radical is united to the tin atom other than by a carbon atom.

These organostannic derivatives of sucrose exhibit a biocidal activity, in particular a fungicidal, algicidal, acaricidal, herbicidal or bactericidal activity. Per unit weight of tin, these activities are often much higher than those of commonly used organotin compounds. In addition, it appears that the rest of the sucrose gives the compounds a solubility in water greater than that of many organotin compounds currently used.

The organostannic derivatives of sucrose, and in particular those in the formula of which m and n represent 0, can be obtained with good yields by relatively simple and direct processes. The product is a mixture of compounds which differ in the position of the bond between the oxygen atom and the remainder of sucrose and in the number of radicals containing tin united with the remainder of sucrose. The mixtures can be refined or purified to give a pure product, but this can be expensive and co-mixing is usually satisfactory since it is effective. In this brief, the simple formula

C00 sacch.

ff i.

LcooLv <

jp 2— 'n therefore also denotes the above-mentioned mixtures.

CH2_7n fsjm SltftW

3

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The compounds in the formula of which m and n represent 0 and p represents 1 are preferred because their preparation is usually simpler and that their bactericidal properties are better than those of the compounds in the formula of which m represents 0, n represents an integer of 1 to 6 and p represents 1, and the remainder of sucrose is therefore directly linked by a carbon / tin bond to the tin atom. When, in the formula, n represents an integer and p represents 1, it is preferable that n represents 2,3,4,5 or 6 and more advantageously 3 or 4, since the intermediaries corresponding to these latter two values, and in particular to 3, are readily available.

As mentioned previously, the nature of the radicals R1, R2 and R3 depends on the fact that the tin atom of the organostannic derivative of sucrose must form three bonds with carbon atoms. Apparently, organotin compounds not comprising three carbon / tin bonds have less marked biocidal activity.

The radicals R1, R2 and R3, which are linked by a carbon / tin bond to the tin atom, are organic radicals such as alkyl, cycloalkyl, aryl and / or alkaryl radicals. The alkyl radical advantageously has 1 to 12 carbon atoms and can be in a straight or branched chain, but it is preferable that it has 1 to 8 carbon atoms, and the results are especially good when the alkyl radical has 4 carbon atoms. , for example is an n-butyl radical, so that if the three symbols R1, R2 and R3 represent alkyl radicals, they together have about 12 carbon atoms for the best results. The cycloalkyl radical advantageously has 3 to 8 carbon atoms and is preferably a cyclohexyl radical. The aryl radical can be a phenyl or naphthyl radical, but preferably is a phenyl radical. These radicals can be unsubstituted or carry 1 or 2 simple substituents, examples of which are lower alkyl radicals, such as methyl and ethyl, halogen atoms such as chlorine, lower alkoxy radicals, such as methoxy and ethoxy, and amino radicals, such as dimethylamino. The alkaryl radical is preferably a benzyl radical.

If one of the radicals represented by R1, R2 and R3 is united to the tin atom other than by a carbon / tin bond, this radical can belong to an inorganic radical or to an organic radical of which the organic part is united to the tin atom other than by a carbon atom.

When one of the symbols R1, R2 and R3 represents an inorganic radical, it can represent for example a halogen atom, such as bromine or chlorine, an inorganic saline radical, such as a nitrate or phosphate radical, or else a valence of an oxygen or sulfur atom, while, when one of the symbols R1, R2 and R3 represents an organic radical united to the tin atom other than by a carbon atom, this can be an ester radical, such as an acetate or p-toluenesulfonate radical.

Preferably, X represents an orthophenylene or ethylene radical, since the compounds in the formula of which X represents a vinylene radical, although they can be obtained in the same way as the compounds in the formula of which X has an orthophenylene or ethylene radical, tend to be more difficult to prepare, because these compounds are somewhat oily.

The compounds in the formula of which m represents 1 and p represents 0 can sometimes be advantageous, since their synthesis can be relatively simple.

The compounds in the formula of which n and m represent 0 and p represents 1, can be obtained by condensation of the sucrose with an anhydride of formula:

where X has the meaning indicated above, giving a sucrose ester of general formula:

C00 sacch.

CO OH

io where X and sacch. have the meanings indicated above, then by reaction of the sucrose ester with an organotin hydroxide or the corresponding oxide of general formula:

R1R2R3SnOH or (R1R2R3Sn) 20

15 where R1, R2 and R3 have the meanings indicated above.

In the first stage of this reaction, the two reagents can be dissolved in a solvent such as dimethylformamide, the resulting ester apparently being a mixture comprising several 1: 1 adducts and some 2: 1 adducts,

20 even a little free sucrose. In the second stage of the reaction, which involves the expensive organostannic compound, the reaction progresses with a high yield which often reaches 85%.

In order to prepare the compounds in the formula of which n represents an integer, m represents 0 and p represents 1, the ester of

Sucrose, for example sucrose phthalate, is first prepared and then converted to a metal salt, for example sodium salt, which is usually the easiest to obtain and the least expensive, before being reacted with an organostannic compound of general formula:

Ph3Sn [CH2] „Br where n has the meaning indicated above and Ph represents a phenyl radical, to give a compound of formula

C00 sacch.

eoo

M n

SnPh-

where X, sacch., n and Ph have the meanings indicated above.

In this compound, the bond between the tin atom and a carbon atom of the aryl (phenyl) radical is more susceptible to attack by halogen atoms than the bond between the tin atom and the carbon atom of the alkylene bridging radical and this compound can therefore be converted by reaction with a halogen, such as bromine, in solution, for example in methanol, at low temperature, to the compound of the invention of formula:

C00 sacch.

C00 (CH2) nSnPh2Br

This brominated compound can be hydrolyzed, if desired, for the elimination of the bromine atom and its conversion into the compound of the invention of formula:

C00 sacch.

C00 (Cïï2) nSnPh2

where X, Ph, sacch. and n have the meanings indicated above.

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4

The compounds in the formula of which m represents 1 and p represents 0 can be obtained by reaction of an ester of general formula:

R1R2R3SnS (CH2) nCOOR

where R1, R2 and R3 have the meanings indicated above, n represents an integer from 1 to 6 and R represents an alkyl radical such as methyl, with sucrose.

The reaction can be carried out in a solvent, such as dimethylformamide, by heating in the presence of an alkaline catalyst, such as potassium carbonate.

The organostannic derivatives of sucrose present in the composition according to the invention have been found to have some good acaricidal activity, some fungicidal activity, some algicidal activity, some herbicidal activity and some bactericidal activity. The organostannic derivatives of sucrose have also been found to be safe for use when spraying on crops, either in the form of a powder or in the form of liquid compositions, since, during exposure to sunlight or when present in the soil, these compounds are believed to break down into inorganic tin compounds which are harmless and do not cause long-term pollution.

As mentioned previously, these organostannic sucrose derivatives have a higher solubility than conventional organostannic biocidal compounds.

Examples of such organostannic derivatives of sucrose are given in Table I. Many of these compounds have been tested for their biocidal activity, the results of which are also given below.

Table I

Compound No.

(n-butyl) 3SnOCOC6H4COO — sacch 1

(phenyl) 3SnOCOC6H4COO — sacch 2

(cyclo-C6H j j) 3SnOCOC6H4COO - sacch 3

(n-butyl) 3SnOCOCH2CH2COO - sacch 4

(phenyl) 3SnOCOCH2CH2COO - sacch 5

sacch.-OCOC6H4COO (CH2) 3Sn (phenyl) 2Br 6

(phenyl) 3SnSCH2COO — sacch 7

The compounds are first subjected to tests against the fungi which usually grow on the paint layers, both inside and outside the buildings. Apparently, there are 16 fungi which are the most frequent and which are: Alternarla alternata (syn. Ternis), Aspergillusflavus, Aspergillus versi-color, Aureobasidium pullulons, Cladosporium herbarum, Curvularia geiculata, Dendryphiella salina, Fusarium oxysporum, Paecilomyces variotii. Penicillium expensum, Penicillium purpurogenum, Pestalotia macrotricha, Phoma violacea, Stachybotrys atra, Stemphylium dentri-ticum and Trichoderma viride.

The efficacy of the compounds with respect to these fungi is evaluated by dissolving these compounds in ethylene glycol monoethyl ether and incorporating the solution with Czapek-Dox agar at the rate of 100 ppm, 10 ppm and 1 ppm. in weight. After hardening, the agar plates are inoculated with spore suspensions of the 16 fungi and the whole is incubated at 25 ° C. for 10 days.

The germination of the spores is then determined, the results of which are given in Table II, which also mentions the results obtained with tributyltin oxide.

(Table at the top of the next column)

As the table shows, most of the compounds have very high activity. The high activity of some of the compounds at a dose of 1 ppm is remarkable, taking into account that the content of

Table II

Compound Number of fungi with inhibition of spore germination (max. 16)

100 ppm

10 ppm

1 ppm

1

16

16

6

2

16

14

4

3

3

0

0

4

16

16

10

5

16

15

9

6

16

7

0

7

16

11

0

Tributyltin oxide

13

13

12

Tin of these compounds is much weaker than that of common organotin biocides, such as tributyltin oxide which is mentioned in Table II.

The fungicidal activity of compounds 1 and 5 is studied in an emulsion paint based on a vinyl acetate copolymer. This painting has the following constitution:

Dioxide RCR 34.2

Sodium hexamethaphosphate (4% solution) .. 1.3

Celacol M450 (4% solution) 8.5

Water 25.6

Vinamul N6815 30.4

At the pigment dispersion stage, the two compounds, as well as the fungicide sold under the name of Friendly 48, are incorporated into samples of this emulsion paint, in different concentrations. a fungicide-free control emulsion on plaster-covered glass tubes and allowed to dry. The properties of a series of immediately painted tubes and those of a second series after 200 h of artificial weather exposure are studied in accordance with BS 3900 F3.

To study the fungicidal power, the painted tubes are seeded using a suspension of a mixture of spores in a 0.01% Tween 80 solution containing at least 104 spores / ml.

We study the following fungi:

a) Alternarla alternata,

b) Aureobasidium pullulons,

c) Cladosporium herbarum,

d) Paecilomyces variotii,

e) Penicillium expansum,

f) Stemphylium dentriticum.

The seeded tubes are then stored under conditions favoring defined condensation on the painted surface and they are kept in incubation for 4 weeks. Next, the growth of the fungi on the painted tubes is evaluated by examination under a stereoscopic microscope, which is evaluated on a scale of 0 to 5, where 0 corresponds to the absence of growth and 5 to general growth.

In addition, all the emulsions are stored for four weeks at 37 ° C., then their color, their odor and their rheology defects are examined.

All the emulsions are found to have satisfactory preservation properties and no disturbing change in color, odor and rheology is apparent after storage. Table III shows the results of the fungicide power tests.

(Table at the top of the next page)

Organotin compounds also find applications in antifouling paints; Enteromorpha s seaweed

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Table III

Compound Quantity Growth assessment

State After 200 h of immediate artificial exposure to the weather

Witness

None

4

3-4

Friendly 48

0.25

1

1

Friendly 48

0.5

0

1

Friendly 48

1.0

0

0

5

0.25

1-2

2

5

0.5

1-2

1-2

5

1.0

1

1-2

1

0.25

2

2

1

0.5

1-2

2

1

1.0

1

1-2

is considered to be primarily responsible for fouling of boat hulls. Table IV brings together the results of a study of the effect of the compounds, at concentrations of 1 and 0.1 ppm, with regard to Enteromorpha in seawater supplemented with nutrients for algae . (+ = effective; - = ineffective).

Table IV

Compound Concentration (ppm)

1 0.1

1. + +

2 ++

3 - -

4 ++

5 ++

6 ++

7 +

These results show that many of the organotin derivatives of sucrose are remarkably active. It is interesting to note that the minimum concentration at which the tributyltin oxide and the tributyltin fluoride usually used are effective in these tests is 0.3 ppm. Sucrose derivatives are therefore at least three times more active. These results are even more remarkable, if we consider that the sucrose derivatives have a tin content much less than half that of commercial biocides as shown in Table V, since tin is expensive.

Table V

Compound% Sn

Tributyltin oxide 39 g

Tributyltin fluoride 3 ^ 4

(butyl) 3SnOCOC6H4COO —sacch 152

(phenyl) 3SnOCOC6H4cOO-sacch 14J

According to current technology, the effectiveness of antifouling paints is extended by incorporating the biocide into the polymer for very slow release of the active agent. The poly-functional nature of the sucrose derivatives allows their easy incorporation into polymers.

The antibacterial activity of organostannic sucrose derivatives is evaluated by growing bacteria both on agar plates and in liquid cultures, the results being collated in Table VI.

Table M

Compound

Escherichia coli

Saccharomyces

Micrococcus

cerevisiae denitrificans

Conc.

Inhib.

Conc.

Inhib.

Conc. Inhib.

(ppm)

(%)

(ppm)

(%)

(ppm) (%)

2

84

100

8

100

0.25 100

1

-

-

-

-

1,100

6

83

23

8

42

1,100

It appears from this table that the compounds must only be present at a very low concentration to suppress the growth of M. denitrificans and that the minimum inhibitory concentration can be much lower than the value in the table, since the latter is the lowest concentration tested.

Some of the above compounds, and in particular compounds 1 and 3, have been found to be effective acaricides. They are subjected to tests according to the leaf immersion technique, the results of which are given in Table VII which allows comparison with conventional acaricides, namely Dibrom and Tedion. As these results show, these compounds are very active.

Table VII

Organization

Compound

Dose (ppm)

Efficiency (%)

Weaver spider mite

3

40

100

(Tetranychus urticae Koch) ..

1

40

100

Dibrom

10

39

Weaver spider mite eggs

(Tetranychus urticae Koch) ..

3 1

Tedion

40 40 2.5

100 96 100

The effect of compounds 1, 2 and 3 is studied with regard to various undesirable vegetation and crops, both in pre-emergence and in post-emergence. It is noted that compound 3 has no significant effect at a dose of approximately 33 g / m2, which indicates an absence of phytotoxicity which is precious for the fight against mites on vegetation. Compounds 1 and 2, on the other hand, have been shown to have some selective effect on undesirable vegetation and crops and therefore appear to be useful selective herbicides. For example, compounds 1 and 2 have no effect on rice, but have high toxicity against, for example, wild oats.

Compounds 1 and 2 have also been shown to exercise useful control over the growth of undesirable aquatic vegetation when present in water at a dose of 2 µm. They are at least as effective as copper sulfate against unwanted aquatic vegetation, and are potentially less toxic to fish than copper sulfate.

Examples of preparation are given below.

Example 1:

A) Preparation of the phthalic hemiester of sucrose

An excess of phthalic anhydride is heated in the presence of

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6

sucrose in solution in dimethylformamide at 60 ° C for 5 h. The reaction progresses according to the scheme:

sucrose

(i)

sacch.

Analysis:

Calculated: C 49.29 H 6.7%

Found: C 50.78 H 7.00%.

Infrared spectrum: 3350 cm-1 (OH region); 1725 cm-1 (> C = 0) (a); 1630 cm "1 (> C = 0) (b).

Example 3

The phthalic sucrose half ester prepared as described in part A of Example 1 is reacted with sodium hydroxide to form the sodium salt, which is then reacted with an excess of the compound of formula Ph3Sn (CH2 ) 3Br in dimethyl formamide at 50 ° C for 3 days, to obtain the compound of formula:

0

II

C 0 sacch.

C _0H

Titration of the resulting ester of formula I using an alkali of known title shows that the ester comprises one acid radical per molecule.

Analysis for a 1: 1: 25 adduct

Calculated: C 48.98 H 5.3%

Found: C 46.6 H 4.8%.

Infrared spectrum: 3400 cm-1 (OH region); 1710 cm-1 (> C = 0) 30

B) Preparation of the organostannic compound

This ester of formula I is reacted with triphenyltin hydroxide or bis (triphenyltin) oxide dissolved in benzene at 50 ° C for 45 min, to obtain the desired compound with a yield of 83% by weight based on the starting organostannic compound.

0 sacch.

0 SnPh-

Analysis: Calculated: Found:

(II)

20

0 (CH2) 3SnPh3

Analysis:

Calculated: C 54.95 H 5.2%

Found: C 54.6 H 5.2%.

Infrared spectrum: 3350 cm-1 (OH region); 1720 cm-1 (> C = 0); 925 and 690 cm-1 (phenyl).

This compound of formula II is then dissolved in methanol and reacted at 50 ° C with bromine to obtain the compound of formula:

sacch.

(or)

Ph I

0 (CH,

0) -jSnBr 2 3 |

Ph

Analysis:

Calculated: C 47.5 Found: C46.8

H 4.64% H 5.29%.

C 54.4 H 4.7%

C 54.6 H 4.8%.

Infrared spectrum: 3350 cm-1 (OH region); 1730 cm-1 (> C0 = 0 typical of organic esters); 1640 cm "1 (; C = O typical of the carboxylate radical united with the tin atom); 730 and 695 cm-1 (phenyl).

55

Example 2

The ester of formula I prepared in Example 1A is reacted with bis (tri-n-butyltin) oxide dissolved in benzene at 40-50 ° C for 45 min to obtain the compound of formula:

0 60

'C 0 sacch.

Infrared spectrum: 3350 cm-1 (OH region); 1720 cm-1 '(> C = 0); 730 and 695 cm-1 (phenyl). (There is a reduction in the ratio of absorption due to the phenyl radical to absorption due to the carbonyl radical.)

This compound of formula III can be hydrolyzed, if desired, to obtain the compound of formula:

r (a)

(b)

B

0 Sn (butyl)

7

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Example 4:

A) Preparation of the succinic hemiester of sucrose

This compound is prepared in the manner described in part A of Example 1 in connection with the phthalic hemiester, that is to say, which is heated at 60 ° C. in dimethylformamide for 5 h, a mixture 5: 1 of succinic anhydride and sucrose which reacts according to the diagram below:

CBg -

Cl ^ -

\,

0 + sucrose

Analysis for C34H40O14Sn:

Calculated: C 51.6 H 5.1%.

Found: C 51.4 H 4.7%.

Infrared spectrum: 1730 cm-1 and 1640 cm-1 (> C = 0); 3400 cm-1 (OH); 690 and 730 cm-1 (phenyl).

Example 6

This example relates to another derivative of the phthalic hemiester. In the same way, with a yield of 80%, the tricyclohexylstannic derivative of formula:

0

C 0 sacch.

0 II

H00CCH2CH2 -C - 0 bag.

The titration of the product shows that its composition is intermediate between the 1: 1 structure and the 1: 2 structure.

0 Sn (C6Hi: L) 3

B) Preparation of an organostannic derivative of succinate

O

O

Analysis for C38H58014Sn:

Calculated: C 53.2 H 6.6%

Found: C53, W H 6.6%.

Infrared spectrum: 1730 cm-1 and 1640 cm-1 (ï C = 0); 3400 cm "1 (OH).

The compound of formula Bu3SnOCCH2CH2C- Ó 3 ° Example 7 sacch is prepared. by choosing reaction conditions similar to those described for the phthalic derivative, this compound being thus obtained with a yield of 75% based on the weight of the starting organotin compound.

Analysis for the 1: 1 adduct:

Calculated: C 46.96 H 7.10%

Found: C 45.95 H 7.20%.

Infrared spectrum: 1730 cm-1 and 1640 cm "'(> C = 0); 3400 cm" 1 (OH).

Example 5

In the same way, O O O is obtained with a yield of 84%.

He II

compound of formula Ph3SnOCCH2CH2CO sacch.

2.0 g (4.4 mmol) of methyl S-triphenylstannylthioglycolate are dissolved in 15 ml of dimethylformamide and the solution is heated in the presence of 4.5 g (13.2 mmol) of sucrose in 45 ml of dimethylformamide and 0.04 g of potassium carbonate at 50-55 ° C for 2 h.

The solution is poured into cyclohexane and the lower phase is washed with several cyclohexane fractions, until most of the dimethylformamide is eliminated. The resulting semi-solid is extracted with chloroform and the solvent is removed. The purification is repeated (washing with cyclohexane and extraction with chloroform) to obtain 1.2 g of a solid which appears to consist of a little unchanged sucrose and a mixture of substituted products.

Analysis for C32H38012SSn:

Calculated: C 50.20 H 4.97%

Found: C 51.42 H 5.58%.

R

Claims (14)

622,407 1. Pesticide composition, containing as active compound an organostannic derivative of sucrose of general formula C00 sacch. i n x i eoo tCH2J a Di S "* 182" 3 15. Composition according to claim 1, containing as active compound the (n-butyl) 3SnOCOC6H4COO — sucrose, or (phenyl) 3SnOCOC6H4COO — sucrose, or 5 (cyclo-C6H11) 3SnOCOC6H4COO — sucrose, or (n-butyl) 3SnOCOCH2CH2COO — sucrose, or (phenyl) saccharose OCS2O2CHO2-CHO2-CHO2-CHO2-CHO2-CHO2-CHO2-CHO2-CHOCHO2-CHO2-CHOCHO2-CHOCHO2-CHOCHO2-CHOCHO2-CHOCHO2CHOCHO 2 -CHO 2 -CHO 2 -CHO 2 -CHO 2 -CHO 2 -CHO 2 -OC 2HOCO 2 -CHO 2 -CO 2 -CHO 2 -CO 2 -CH 2-CO 2 -CHO 2 -CHO 2 -CO 2 -CO 2 -CH 2 O 2 CO 2 -CHO 2] (CH2) 3Sn (phenyl) 2Br, or (phenyl) 3SnSCH2COO-sucrose. 16. Use of the composition according to claim 1 as acaricide. where sacch. represents a sucrose residue, X represents an orthophenylene, ethylene or vinylene radical, m represents 0 or 1, p represents 0 when m represents 1 and represents 1 when m represents 0, n represents 0 or an integer from 1 to 6, being understood that, when m represents 1, n is an integer from 1 to 6, and R1, R2 and R3, identical or different, represent radicals such that the tin atom is united by three valences to carbon atoms and by a valence to an atom other than carbon. 2. Composition according to claim 1, containing an organostannic derivative of sucrose of general formula COO sacch. I X COojcH ^ SnR ^ R3 where sacch. represents a sucrose residue, X represents an orthophenylene, ethylene or vinylene radical, n represents 0 or an integer from 1 to 6 and R1, R2 and R3, identical or different, represent radicals such that the tin atom is united by three valences to carbon atoms and by one valence to an atom other than carbon. 2 3. Composition according to claim 2, in the formula of which n represents 0 or an integer from 2 to 6. 4. Composition according to one of the preceding claims, in the formula of which one or more of the symbols R1, R2 and R3 independently represent alkyl, cycloalkyl or aryl radicals. 5. Composition according to claim 4, in the formula of which any alkyl radical represented by R1, R2 or R3 has 1 to 8 carbon atoms. 6. Composition according to claim 5, in the formula of which any alkyl radical represented by R1, R2 or R3 is a butyl radical. 7. Composition according to claim 4, in the formula of which any cycloalkyl radical represented by R1, R2 or R3 is a cyclohexyl radical. 8. Composition according to claim 4, in the formula of which any aryl radical, represented by R1, R2 or R3 is a phenyl radical. 9. Composition according to one of the preceding claims, in the formula in which one or more of the symbols R1, R2 and R3, independently, represent alkaryl radicals. 10. Composition according to one of the preceding claims, in the formula of which n represents 0. 11. Composition according to one of claims 1 to 9, in the formula of which n represents an integer. 12. Composition according to claim 11, in the formula of which n represents 3 or 4. 13. Composition according to claim 11 or 12, in the formula of which one of the symbols R1, R2 and R3 represents a valence of an oxygen atom, a chlorine atom or an ester radical. 14. Composition according to claim 11 or 12, in the formula of which one of the symbols R1, R2 and R3 represents a valence of a sulfur atom, a halogen atom, an inorganic saline radical, or a p-toluenesulfonate radical.