FI56919C - TILLVAEXTREGULATORER - Google Patents

Description

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Patents and registers' 7 AnsOkan utlafd och utl.skrlften published O-L. UI. Ö0 (32) (33) (31) Claim claimed — Begird prloritet 03.08.72 26.02.73, 02.01 + .73 USA (US) 277538, 335607, 31 + 7035 (71) F. Hoffmann-La Roche & Co. Aktiengesellschaft, Basel, Switzerland-Switzerland (CH) (72) William Szkrybalo, Verona, N.J., USA (7! +) Oy Kolster Ab (5I +) Growth regulators - Tillväxtregulatorer

The invention relates to preparations for controlling plant growth, which are characterized in that they contain, in addition to the usual carriers, as active ingredient a sufficient amount of one or more of the general formula> 0 / o o * -

/ \ C-0 - R.XHgO I

S

The compound of formula 56919 wherein n is 1, R is hydrogen; sodium; potassium; ammonium; ammonium substituted with one or more C 1 -C 4 alkyl or C 1 -C 4 hydroxyalkyl; C ^ -C ^ alkyl; Cg-Cg alkenyl; C 8 -C 8 alkynyl or halo-lower alkyl; and when n is 2, R is calcium, magnesium or lower alkylene, R 1, R 8, R 6 and R 4 are hydrogen or C 1 -C 4 alkyl, n is a number 1 or 2, and X is a number 0 -1; as an enantiomer or racemic mixture.

These preparations are particularly useful as plant growth regulators after and before germination and as herbicides.

The compounds of formula I all have the L-configuration because they are all due to the naturally occurring ketohexose, L-sorbose. L-sorbose is the only known naturally occurring form of sorbose; however, the enantiomer corresponding to L-sorbose, namely D-sorbose, can be prepared synthetically. In particular, it is pointed out that compounds corresponding to L-sorbose having the D-configuration and racemic mixtures of these compounds can be prepared in a completely analogous manner by using D-sorbose instead of L-sorbose as starting material or by using a mixture of D- and L-sorbose, respectively. the purpose is to prepare a racemic mixture. The production methods are exactly the same regardless of whether a compound in L-form or D-form or a similar racemic mixture is used as a starting material. Correspondingly, with respect to all the structural formulas presented later and above, it is to be understood that they do not describe only a definite or absolute configuration, these structural formulas of the population describe all possible configurations, i. they include in particular enantiomers and racemic mixtures. The examples and other descriptions apply, unless expressly stated otherwise, to racemic mixtures.

The compounds of the formula I have post-emergence and / or pre-emergence plant growth-regulating activity and herbicidal activity. However, after germination, the growth-regulating effect is more predominant because most compounds have this effect and because this activity is suitable for controlling the growth of weeds in the grass field.

As used herein, the term "lower alkylene" means a divalent straight-chain or branched alkylene group having 1 to 7 carbon atoms and bonded through two different carbons. The term "alkyl" includes both straight chain and branched alkyl groups such as methyl, ethyl, n-propyl, isopropyl and n-butyl. Examples of alkenyl or alkynyl groups which may be straight-chain or branched include allyl, propenyl, butenyl, pentenyl, 1,1-dimethylpropenyl, propargyl, butynyl, pentynyl, hexadynyl and possible isomers of these compounds. A particularly preferred alkynyl group is a propargyl group.

3,56919

The term "lower alkyl" in combinations such as halogen-lower alkyl means straight-chain or branched alkyl groups having 1 to 7 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, tert-hutyl, pentyl, etc. The term "halogen" "lower alkyl" comprises straight-chain or branched alkyl groups having 1 to 7 carbon atoms and in which one or more hydrogen atoms have been replaced by halogen, such as, for example, 2,2,2-trichloroethyl, 2,2-dichloroethyl, 2-chloroethyl, 4-chloro -butyl, 2,2,2-trifluoroethyl, 2-fluoroethyl, 2-bromo-1,1,2,2-tetrafluoroethyl, 2,2,3,3,4,4,4-heptafluorobutyl.

Examples of representatives of the formula I which have potency as plant growth regulators and / or herbicidal activity are the following: 2.3.0-isopropylidene-4,6,0- (3-pentylidene) -2-keto-L-gulonic acid, 2.3. O-isopropylidene-4,6,0- (2-butylidene) -2-keto-L-gulonic acid, 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate, 2,3: 4,6-0- (2-butylidene) -2-keto-L-gulonic acid.

Furthermore, salts of these aforementioned gulonic acids, for example alkali, alkaline earth, ammonium and substituted ammonium salts, as well as esters, for example lower alkyl, lower alkenyl and lower alkynyl esters, are also effective as plant growth regulators and / or herbicides.

Preferred compounds for the invention are: 2,3: 4,6-di-O-1-sopropylene-2-keto-L-gulone acid monohydrate, allyl-2,3: 4,6-di-O-isopropylidene-2-keto -L-gulonate, potassium 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, 11,56919 ammonium 2,3,4,6-di-O-isopropylidene-2-keto-L-gulonate i, Potassium 2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, dimethylammonium 2,3 * 4 * 6-di-O-leopropylidene-2-keto-L-gulonate , N-ethanolammonium-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, methyl 2,3 * 4,6-di-O-leopropylidene-2-keto-L -gulonate, ethyl 2,3 * 4 * 6-di-O-ieopropylidene-2-keto-L-gulonate, n-butyl-2,3 * 4,6-di-O-ieopropylidene-2-keto-L gulonate, 3-chloropropyl-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, n-hexyl-2,3 * 4,6-di-O-leopropylidene-2-keto -L-gulonate, n-heptyl-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, n-octyl-2,3 * 4,6-di-O-leopropylidene-2 -keto-L-gulonate, n-nonyl-2,3 * 4,6-di-O-eopropylidene-2-keto-L-gulonate, n-undecyl-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, 2,2,2-trichloroethyl 2,3,3,4-di-O-leopropylidene-2-keto-L-gulonate, n-dodecyl 2,3 * 4,6-di-O-iopropylidene-2-keto-L-gulonate, n-propyl 2,3,3,4,6-di-O-ieopropylidene-2-keto-L-gulonate, 1- propyl 2,3,3,4,6-di-O-leopropylidene-2-keto-L-gulonate, n-Decyl-2,3,3,4-di-O-leopropylidene-2-keto-L-gulonate, 2-Bromoethyl 2,3,3,4-di-O-leopropylidene-2-keto-L-gulonate 2-butyl-2,3 * 4,6-di-O-leopropylidene-2-keto-L- gulonate, 1-amyl-2,3 * 4,6-di-O-ieopropylidene-2-keto-L-gulonate, bie-2,3 * 4,6-di-O-ieopropylidene-2-keto-L- gulonate ethylene glycol ether, t-butyl 2,3-4 * 6-di-O-leopropylidene-2-keto-L-gulonate, 2-pentynyl-2,3 * 4,6-di-O-leopropylidene-2-keto- L-gulonate, 1-hexyn-3-yl-2,3 * 4,6-di-O-o-propylidene-2-keto-L-gulonate, 3-ethyl-1-butyn-3-yl-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, 5-hexenyl-2,3 * 4,6-di-O-leopropylidene-2-keto-L-gulonate, 3-pentyl-2, 3 * 4,6-di-O-ion propylidene-2-keto-L-gulonate, dichloromethyl-2,3 * 4,6-di-O-iopropylidene-2-keto-L-gulonate, 2,2-dichloroethyl-2,3,3,4-di-O- Ieopropylidene-2-keto-L-gulonate »2-chloroethyl-2,3 * 4,6-di-O-ieopropylidene-2-keto-L-gulonate, 4-chlorobutyl-2,3 * 4,6-di- O-Iropropylidene-2-keto-L-gulonate, 2,2,2-trifluoroethyl-2,3 * 4 * 6-di-O-ieopropylidene-2-keto-L-gulonate, 2-fluoroethyl-2,3 * 4, 6-di-O-leopropylidene-2-keto-L-gulonate, 2-broal-1,1,2,2-tetrafluoroethyl-2,3: 4,6-di-O-isopropylidene-2-keto-L- gulonate,,? 5,56919 2,2,3,3,1 +, 1 + -heptafluorobutyl 2,3-4,6-di-O-isopropylidene-2-keto-L-gulonate, 2,2,3,3,1+, 1 +, 5,5-octafluoropentyl -2,3: 1 +, 6-di-O-isopropylene -2-ketol-gulonate.

Particularly preferred compounds are:

Sodium 2,3: 1+, 6-di-O-isopropylidene-2-keto-L-gulonate, 2-propynyl-2,3: 1+, 6-di-O-isopropylidene-2-keto-L- gulonate, n-pentyl-2,3: 1 +, 6-di-O-isopropylidene-2-keto-L-gulonate.

The active compounds are particularly useful in plant growth control preparations, especially in the growth control of grasses and weeds and also other undesired plants which have accidentally been mixed with deliberately cultivated plants. Although the compounds have a plant growth regulating effect before germination, they are particularly useful when used after germination to regulate plant growth or as a fruit fall agent. The post-emergence efficacy of the compositions containing the active compound in the context of the present invention is demonstrated by the control of the growth of undesired plants. Thus, it has not hitherto been possible to control post-emergence blood millet growth, however, with the post-emergence herbicide this is achieved with the preparations of the present invention which strongly retard the growth and inflammation of this herb and thus prevent the seeding and spreading of this grass.

Lawn control, especially yard and industrial lawns (e.g., golf courses), has shown that a maximum growth retardation of about 1 + 0-60% must be sought, which can be shown as a decrease in grass height compared to untreated control, with $ 50 being the most preferred. slowing of grass growth. A deceleration of less than 1 + 0% must already be considered ineffective, because then the necessary aesthetic effect cannot be detected visually and the necessary care work on the lawn is not reduced. On the other hand, a growth slowdown of more than 60% is not desirable because the lawn gets a barren appearance and weeds and other unwanted plants begin to grow rapidly.

6,56919

The active compounds show a herbicidal action, in particular against wading weeds, for example Matricaria species, and other weeds, such as Papaver rhoeas, Stellaria media and Capsella Bursa pastoris.

The compounds are particularly active against the following plants: a) grasses such as Agropyran repens, Bromus inermis, Bromus erectus, Deschampsia flexuosa, Alopeeurus pratensis, Arrhenatherum elatius, Dactylis glomerata, Festuca pratensis, Trisetum flavescens, Holcus lanatue, Lolium perenne, neumoralis, Festuca ovina, Festuca rubra, Festuca nigrescens, Cynosurus cristatus, Agrostis schraderiana, Agrostis stolonifera, Phleum pratense, Phleum nodosum, Cynodon dactylon, Stenotaphrum secundatum, Paspalum notatum, Ermochloa olit sugar cane and cereals such as rice, wheat, rye, barley, oats, etc., (b) trees and shrubs such as fruit trees such as apple, pear, peach, cherry and citrus trees, and cocoa, tea, coffee, banana , rubber, olive and walnut trees; (c) ornamental plants such as thyme, white beech, light cedar, juniper, rose, azalea, xysanthemums, Poinsethia, alpine pansy, Pyracantha, forsythia, magnolias, petunias and bromeliads; (d) arable crops such as cotton, soybeans, peanuts, tobacco, flax, sugar beet and pineapple; (e) vegetable species such as Solanaceae (eg tomatoes), legumes, pumpkin, melon, etc .; (f) berries such as strawberries, blueberries, raspberries, blackberries and currants.

These compounds are also useful because they reduce the need to prune vines in vineyards.

In order to obtain a uniform distribution of the active compounds in the growth regulators of the invention, the compound or compounds are mixed with conventional excipients, modifiers, diluents or humectants commonly used in herbicides to form soluble, emulsions, emulsifiable concentrates, dispersions, powders, dusts .

Liquid compositions of the active ingredient or ingredients for direct injection may be prepared, for example, as aqueous solutions, where possible, or as solvent mixtures containing, for example, acetone, methanol, dimethylformamide in a ratio of 90: 8: 2 (v / v). In the case of 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid, also known as DAG, buffered (pH 5-β) compositions are prepared, for example by adding potassium hydrogen sulphate or organic amines such as diethanolamine, triethanolamine, etc. in aqueous solutions containing 1 io Tween 20 or other non-phytotoxide wetting agents. Buffering of solutions is necessary because it is known that MG is unstable in aqueous solutions below pH 5 m.

Emulsifiable concentrates containing 25 to 50% or more of active ingredient, depending on its solubility, can be prepared using suitable solvents, for example N-methylpyrrolidine, dimethylformamide, etc., surfactants, for example wetting agents, dispersants, emulsifiers, etc., are added in a sufficient amount. the desired properties of the composition.

The various uses can be more easily adapted to the many purposes for which the active compounds can be used by adding compounds which improve dispersion, adhesion, rain resistance and penetration, such as fatty acids, waxes, resins, wetting agents, emulsifiers, mineral or vegetable oils, Likewise, the biological spectrum of these compounds or preparations can be greatly extended by the addition of substances having bactericidal, herbicidal, fungicidal properties, or by the addition of fertilizers, chelating agents or other plant growth regulators.

Examples of herbicides and growth regulators which can be mixed with the preparations according to the invention are: 2,2-dichloropropionic acid, H- (4-aminobenzenesulphonyl) methylcarbamate, 2-chloro-4-ethylamino-6-isopropylamino-1,5,5-triazine, 4 - chloro-2-oxobenzothiazolin-3-ylacetic acid, 5-bromo-6-methyl-3- (1-methyl-n-propyl) urea, 3,5-dibromo-4-hydroxybenzonitrile, DN-ethyl-2- ( phenylcarbamoyloxy) propionamide, N- (4-bromo-3-chlorophenyl) -N'-methoxy-N'-methylurea, methyl 2-chloro-9-hydroxyfluorene-9-carboxylate, H'-4- (4- chlorophenoxy) phenyl N, N-dimethylurea, isopropyl N- (3-chlorophenyl) carbamate, 2,3,5,6-tetrachloroterephthalic acid dimethyl ether (DCPA), 2,4-dichlorophenoxyacetic acid, 4-iopropylamino-6- methylamino-2-methylthio-1,3,5-triazine, n-butyl-9-hydroxyfluorene-9-carboxylate, ethylene, naphthoxyacetic acid, 56919 3,6-dichloro-2-methoxybenzoic acid, (-) - 2- (2, 4-Dichlorophenoxy) -propionic acid o, 9,10-dihydro- 8α, 10α-diazonophenatren-2A, N '- (3,4-dichlorophenyl-N, N-dimethylurea, Gibb ericylic acid, indolylacetic acid, indolylbutyric acid, 4-hydroxy-3,5-diiodobenzonitrile, N' - (3 , 4-dichlorophenyl) -N-methoxy-N-methylurea, 4-chloro-2-methylphenoxyacetic acid, 4- (4-chloro-2-methylphenoxy) butyric acid, (-) - 2- (4-chloro-2 -methylphenoxy) propionic acid, N- (benthothiazol-2-yl) -N, N'-dimethylurea, N '- (3-chloro-4-methoxyphenyl) -N, N-dimethylurea, 1.2. 3,6-Tetrahydro-3,6-dioxopyridazine, N, - (4-chlorophenyl-N-methoxy-N-methylurea, N '- (4-chlorophenyl) -N, N-dimethylurea, naphthylacetic acid, N1-naphthylphthalamic acid , 2,4-dichlorophenyl-4-nitrophenyl ether, 1,1'-dimethyl-4,41-bipyridyl-2A, 3- (m-tolylcarbamoyloxy) phenylcarbamate, 4-amino-3,5,6-trichloropicolinic acid, 4,6-bis-isopropylamino -2-methylthio-1,3,5-triazine, N- (3,4-dichlorophenyl) propionamide, isopropyl N-phenylcarbamate, 5-amino-4-chloro-2-phenylpyridine Ridazin-3 (2H) -one, N-dimethylaminosuccinic acid, 2-chloroethylphosphoric acid, tributyl-2,4-dichlorobenzylphosphonium chloride, 2,4,5-trichlorophenoxypropionic acid, 2,3,6-trichlorobenzoic acid, 2-chloro-4,6-bis-b,6-bis-b,6-bis-b,6-bis-b,6-bis , 3,5-triazine, sodium chloroacetate, 2,4,5-trichlorophenoxyacetic acid, 5-chloro-6-methyl-3-t-butylurazine, 4-ethylamino-2-methylthio-6-t-butylamino-1,3,5- triazine (tetbutryn), 2,3,5-triiodobenzoic acid, 1,1,4-trimethyl-6-isopropyl-5-propion-3-ylindan.

9,56919

Examples of fungicides which can be added to the preparations according to the invention are: _____ 2,4-dichloro-6- (o-chloroaniline) -S-triazine, 2,4 * 5 * 6-tetrachloroisophthalic acid nitrile * p-dimethylaminophenyldiazonium sulphonate, 1 * 4 -dichloro-2 * 5-dimethoxybenzene * manganese ethylene bis-dithiocarbamate * zinc ethylene bis-dithiocarbamate »coordination product of zinc and manganese ethylene bis-dithiocarbamate, methyl 1- (butylcarbamoyl * 4-benzimidyl) -2-benzim thiazole) -benzimidazole, cis s - - [(trichloromethyl) thio] -4-cyclohexene-1 * 2-dicarbochimide.

The application rates reported are based on the results presented here * and have not been reported to such an extent that all possible cases were included, as several factors affect the application rates * Application rates vary not only for different plant species but for a given plant species depending on factors such as plant size, plant age , compound used, season, soil quality and weather conditions at time of application, such as air temperature, light intensity, rain and wind * If additional compounds or preparations are used by irrigating the soil, higher concentrations are required as the plant will be treated indirectly compared to direct application. preparation on the leaves or stem, for example, by spraying the plant.

The amount of active ingredient in the plant growth regulators thus varies depending on the plants to be controlled, the amount of application required, the mode of application, the active ingredient used and the extent of plant growth control desired. Generally, formulations contain less than $ 50 of active ingredient in ready-to-spray form.

In principle, the amount of active ingredient to be used has been chosen so as to achieve effective control of plant growth. As already exemplified above, the amount of active ingredient used in lawn control is such that the normal growth rate is slowed to 40-60. Similarly, the choice of the minimum application rate is determined by the minimum amount that can cause the desired growth retardation at the lower limit. Accordingly, the maximum application rate is determined by the amount of active ingredient which gives the desired growth retardation at the upper limit, i. in the case of grasses used for ornamental lawns, the amount which still avoids the poor growth appearance of the ornamental lawn but which, on the other hand, prevents too rapid lawn growth and does not cause undesirable 10 S6919 chlorosis (i.e. * yellowing of the grass). In tomato plants, the selection criteria for effective growth retardation are different because a dwarf plant that does not cause losses in fruit quality or quantity is highly desirable. Parameters of effective growth-regulating activity in such plants are retarded height growth and increased or non-retarded side growth as a minimum effect and retarded height and side growth as a maximum effect. According to these considerations, the amount of active substance which satisfies these selection criteria or produces these effects is determined on tomato plants. In order to obtain the greatest post-emergence growth-regulating effect, 0.5 to 20 kg or more per hectare is used. These amounts are based on the weight of the active substance. Similarly, the maximum post-emergence growth-regulating activity is generally obtained in amounts of 1-15 kg or more of active ingredient per hectare. The preferred dosage range for spray solutions is from 10 to 100,000 ppm, depending on which plant species is treated and which compound is selected for treatment. A very preferred dose range is generally 100-20,000 ppm.

An additional advantage of using the preparations according to the invention is that they do not have any permanent effect on plants or a regulating effect which would remain in the soil. These compounds degrade slowly and result in a decrease in activity »This phenomenon has advantages in that a) a short-term effect is obtained which can be prolonged by further treatment; (b) normal plant growth conditions reappear as activity decreases; (c) no harmful residues remain on the plant or in the soil.

The duration of the retarding effect varies depending on the compound used and other factors such as the species of plant treated, weather conditions, etc. *

Although the compounds of the formula I have growth-regulating properties and herbicidal activity in plants, they are practically non-toxic to animals. For example, rats fed either 31AG or its sodium salt at a rate of 4 g / kg body weight did not die, the "1d" is about 16 g / kg (mouse / decomposition products, first 2-keto-L-gulonic acid and finally carbohydrates, are likewise non-toxic.

It is self-evident that not all compounds of the formula I are active in all plants. However, within the scope of the present invention, each of the active associations exhibits activity against a particular plant or plants, and this activity is one of the purposes of the compound. As will be described in more detail below, it is a particular advantage of the present invention that the growth regulators, when used to treat a variety of plants, develop pre- and post-emergence growth-regulating potency and herhicidal activity, with a very wide range of relevant plants. activity is supported by the following micro-experiments to determine the activity of the post-emergence effect * A. Experiments with 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid and its salts and esters.

The growth inhibitory effect of the preferred compounds is demonstrated in the following herbs in greenhouse experiments, especially after emergence in experiments with Ligitaria sanguinalis and Poa pratensis *

The test compounds are dissolved in a solvent mixture of 90 volumes of acetone, 8 volumes of methanol and 2 volumes of dimethylformamide.

Blood millet (Digitaria sanguinalis) was 10 days old and slightly less than 2.5 cm high · Poa pratensis was also cut to a height of about 2.9 cm before the compounds in question were used.

Compounds were sprayed at rates of 0.5-8 kg / ha on grasses. Effect i.e. growth retardation was determined by measuring grass height and grass weight, i. weight of cut grass after 11-26 days.

The experiments included 3 standard compounds as controls. Maleic acid hydrazide (6-hydroxy-3- (2H) -pyrridazinone) was used as an aqueous solution, i.e. as a water-soluble concentrate (300 g / l). Further, n-butyl 9-hydroxyfluorene- (9) -carboxylate, hereinafter referred to as IT-3233 *, and methyl 2-chloro-9-hydroxyfluorene- (9) carboxylate, hereinafter referred to as IT-3456, were used in the solvent mixture described above. *

Other reference compounds that can be used are CCC (2-chloro-ethyltrimethylammonium chloride), Alar (N-dimethylaminosuccinic acid), 2,4-D (2,4-dichlorophenoxyacetic acid), MCPA (2-methyl-4-chlorophenoxyacetic acid), CMPP (2-methyl-4-chlorophenoxypropionic acid), Ioxynil (3,5-diiodo-4-hydroxybenzonitrile) and Ethrel (2-chloroethylphosphoric acid).

The test results are summarized in the following Tables I and 11.

12 56919

song song I

Growth retardation effect of 2,3: 4,6-di-O-iopropylidene-2-keto-L-gulonic acid MG and its derivatives after germination

Grass height (cm) 11, 18 and 26 days after treatment

Compound Dose Digitaria Poa kg / ha sanguinalis pratensis 11 days. 18 days. 26 days.

Untreated · control 10 '11.7 7 »0 8 1.67 4.0 3.5 mg 4 3.0 5.3 J.5 2 3.8 7.5 b · 0

1 5.2 9.0 ö.O

0.5 7.2 11.3 7.0 MG-methyl-8 2.3 3 · 3 .3.0 ester 4 3.5 6.7 5.0.

2 5.5 10.8 6.0 1 7.0 11.8 7.5 0.5 10.2 12.3 7.0 MG ethyl ester 8 2.2 6.3 6.0 4 4.3 8.3 7.5 2 8.2 10.8 7.5 1 9.5 11.8 6 · 5; 0.5 11.5 12.3 6-5 MG-n-butyl-8 3.0 5 * 7 ester «3.7 6.7 * -5 2 5.3 5.3 7.5 1 7.5 11.5 7.5 0.5 9.2 13.3 MG-allyl ester 8 2.5 3.0 3.5 4 3.2 6.2 ή.5 2 5.0 10.0 5.0 1 6.7 12.0 7.0 • 0.5 8.8 13.0 7.0

Maleic acid 4 5.8 6.3 4.0 hydrazide IT-3233 1 8.8 12.5 IT-3456 1 8.7 9.8 5.5 13 56919

Table II

Digit of the green grass tips of Digitaria sanguinalis and Poa pratensis after pruning after treatment with growth retardants.

Weight in gto »days after treatment

Compound Dose kg / ha Digitaria Poa _ sanguinalia Pratensis 18 days. 26 days.

. control ~ 18-9 DAG 8 ή.k. 2.7 4 9.0 5.2 2 14.0 5.7 1 12.4 8.5 0.5 20.8 4. 4 MG-methyl 8 6.1 2.7 ester 4 13.0 5-3 2 18.3 5.3 1 19.3 5.7 0.5 19.ή 5.7 DAG ethyl ester 8 10.0 3 * 5 il 13.5 5.3 2 18.3 5.1 1 19.3 i * .2 0.5 0.5.9 3.2 DAG-n-butyl-8 6.2 3.0 ester 10.2 4.2 2 17.9 J.3 1 19.6 Jl 0.5 21.1 8 DAG-allyl-8 8.3 2.0 ester il 1 * 1.9 4.0 2 18.8 3.7 1 20.1 3.3 0.5 21.1 5.0

Maleic acid i i |. 7 1 · 9 hydrazide IT-J2J3 1 10. <t 4.4 IT-3456 1 10.2 4.2 pages 56919

Of the compounds tested, 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid (DAG) has been shown to be the most active in inhibiting the growth of Digitaria sanguinalis *, with methyl, n-butyl and allyl esters having a similar effect. At comparable doses, MG is more effective against Digitaria sanguinalis * and Poa pratensis than maleic acid and both other reference compounds.

When solutions of common solvents are not very suitable under field conditions, MG and similar derivatives were tested as emulsifiable compositions. (25 i »active ingredient, 41 xylene, 2 # Atlox 3404, 2 Atlox 3403 *). Several esters were studied in said solvent mixture. In addition, aqueous solutions containing MG, 1% Tween 20 (polyoke sorbitan monostearate) were prepared both unbuffered and buffered to pH 5-7. Aqueous solutions of MG salts, which also contained Tve 20, were also included in the experiments.

Well-retarding studies were performed on a plant spectrum comprising, for example, Digitaria sanguinalis, soybeans, and tomatoes, where the plants were treated at approximately 2 weeks of age. When treated, Digitaria sanguinalis was approximately 2 cm high, soybean plants with first leaves about 5-6 cm high, and tomatoes with 3-4 actual leaves were 3-4 cm high. Water-soluble, solvent mixtures or emulsifiable concentrates of the active ingredients were sprayed.

The results of these experiments with MG, its salts and esters in different compositions are shown in Table III, where the deceleration potency is shown in numbers. The rating scale is defined as follows: 0 - no visible growth retardation 1, 2, 3 - slight retardation, plants show little or no growth retardation in visible parts of the plant 4, 5, 6 - moderate growth retardation, plants show reduced growth in visible parts of the plant 7, 8, 9 - strong deceleration, little or no growth in plants 10 - no growth.

Atlox 3 ^ 03 is a mixture of polyoxyethylene ethers, polyoxyethylene glycerol and alkyl aryl sulfonate. Atlox 3 + + (A is a mixture of polyoxyethylene alkylaryl ether and alkylarylsulfonate. Atlox products are manufactured by Atlas Co. USA.

t 15 S 6919

Table III

Herbicidal activity after germination of MG and derivatives.

Retarding effect 1? vrktssa

Compound Form Dose kg / ha Digitaria Soy- Tomato sanguinalis bean

• MG «SM

8 8 6.7 8 4 7 3 8 2 6 3 7.3 1 5 2 5 0.5 4.3 1 1.1 MG water 8 9 9 10 4 9 8 9.7 2 8 7 9 1 6 6.7 8.7 0.5 5 6.7 8.3 »MG water 8 9 9 10 4 9 9 9 2 7.7 7.7 8.3 1 6.7 7 7 0.5 468 MG-water 8 8.3 9 9 sodium Ij 9 8 8 salt 2 7 6.3 5.7 1 '4 3.7 6.3 0.5 3 0 3 MG-water 8 9 9 8 potassium - 4 9 8 7.7 'salt 2 7.3 7.3 6.7 1 5 3 4.7 0.5 2 0 5 MG water 8 9 9 9 ammonium- 4 9 7 * 7 8 salt 2 8 6.7 6 1 f' 3.3 5 0.5 42 5 1 «56919

Table III (continued)

Delay effect 1} in the network

Compound Form Dose kg / ha Digitaria Soy- Tomato sanguinalis bean MG water 8 9 9 9

Calcium- i 8 8 9 salt 2 8 7.3 6 1 4.7 3 5 0.5 3.7 1 5 mg- 8 9 9 7.7 methyl 4 8 3 5 ester 2 4 1 3.3 1 3 0 0 0.5 000 DAG-n-SM 8 9 6 7 butyl 4 8 6 6.7 ester 2 735 1 5 1.3 5 0.5 4 0 0 MG-n- EC 8 10 9 8 butyl 9.3 9 7.3 ester 2 7.7 8.3 8 1 5.7 7 8 0.5 3.7 5 3

Maleic acid 8/10 5.7 hydrazide 4 t 10 3 4 2 5 9 1 water i 090 0.5 0 9 0 IT-3456 SM 8 5.7 8 5 4 5 8 5 2 3 8 5 1 0 8 5 0.5 0 8 5.

t 17 56919

Table III (continued)

The deceleration effect 1} days

Compound Form Dose kg / ha Digitaria Soy- Tomato sanguinalis bean

JiSyii- 8.1 8. 8.3 8 9 J 7.3 8 8.3 2 5.3 7.3 5 1 k 1.3 1 0.5 2.7 0 9 MG-n-dode- g 5 8 alkyl 4 7 3 7 ester SM. 2 4 3 6.3 1 2 2 2.3 0.5 2. 2 2 f MG-n-t EC 8 8.7 8.3 '8.3 dode- 4 8 6.3 ^. 3 kyl ester 2 .3 5 · M .3 '1 3 5 5 0.5 05 3

Control EC - - 5,3 k SM - active substance dissolved in solvent EC - emulsifiable concentrate water - a) for MG salts, water contains 1 $ Tween b) for DAG, water pH is adjusted to 5 ^ si and 1 #

Tween and 10 56 isopropyl alcohol.

18 56919 The activity of DAG in aqueous solutions is enhanced by buffering to pH range 5-8, which effect must be calculated due to the increasing stability of DAG in this pH range. This reinforcing effect was greater in soybeans and tomatoes than in Digitaria sanguinalis. The inorganic salts and esters of DAG were almost as active as DAG itself. The experimental results show that DAG, its salts and esters are more active than maleic anhydride and the reference compound IT 3 ^ 56 in post-emergence growth inhibition in Digitaria sanguinalis and only slightly less active in post-emergence growth inhibition in soybeans.

19 56919

In Table III, the dosage of salts, esters and other analogs and DAG was not adjusted to correspond to the equivalent amount of acid.

Although the main field of application of the growth regulators according to the invention is use for growth control after germination, the active compounds of the formula I can also be used before germination. The pre-emergence activity of MG compounds is demonstrated by the n-propyl ester of DAG. The ester is sprayed at a rate of 8 kg / ha. A strong growth retardation (i.e. little or no growth) is observed in Sorghum halepense, Amaranthus sp. and Digitaria sanguinalis after 20 and 27 days.

Further studies with DAG and its salts were performed on a wide variety of grasses, cereals, ornamentals, perennials, and vegetables.

Growth retardation studies were performed on a number of herbs using emulsifiable concentrates containing DAG in nitropyrrolidone. All species except Lolium were sprayed k days after surgery. Lolium was cut and sprayed on the same day. Effect on plants, i.e. growth retardation, was determined by measuring grass height at 19 and 21 days after spraying.

Maleic acid hydrazide (MH) and chlorofluorol (CF) were used as reference materials. The results are shown in the following Table IV:

Table IV

20 56919

Growth-promoting activity after germination A. Growth retardation 19 days after this day »grass height cm

Compound DAG DAG DAG MH Untreated control

Dosage to o / kg ..1. Vh. 12 18 24 5

Huoholaji

Agropyron 7 * 2 6 · 3 5 * 3 10 ♦ 7 14 * 7 repens

Bromine inerais 10.2 8.2 7 · 3 12.3 14 * 3

Bromus erectus 8.5 7 * 7 7.7 9 * 5 12.0 3.2 3.4 3.4 3.3 3.6 10.3 9.7 7.7 14.3 17.0

Arrhenatherua elatiue 7 · 8 7.3 6 * 0 11.7 16.7

Dactyl! S glomerata 11 * 7 10.8 9 * 7 13 * 3 18.0 p ^ eaeie 9.5 8-5 7.7 12.0 14.3 flavescens 9 * 0 8.5 9 * 7 11 * 7 38.0

Holous lanatus 8.0 7 * 7 7 * 8 10.5 14 * 3

Lolium per before 14.3 12.7 13 * 3 13 * 3 18.7 x a.i. * active substance 'V' 21 56919 S. Growth retardation after 21 days, grass height, cm

Compound DAG MG MG CF Untreated 'Dosage control kg a.i./ha 4 8 16 1

grass Species

Poa annua 8.7 7.3 7.0 7.5 8.7

Poa nemoralis 18.3 6 * 8 7.2 8.7 22.3.

Festuca ovina 14.0 7.5 9.3 9.0 15.0

Pestuca rubra 18.3 13.3 12.8 11.7 18.7

Festuca nigrescens 13.0 8.5 8.3 10.5 12.8

Cynosurua cristatus 10.7 6.8 7.0 9.5 12.0

Agrostis schraderiana 6.7 4.7 5.0 5.3 7.7

Agrostis stolonifera 6.7 4.0 4.0 5.2 6.7

Phleum pratense 11.7 11.0 10.7 10.8 12.3

Phleum nodosum 7.3 6.5 7.0 7.0 8.2

Cynodon dactylon 10.8 7.3 7.3 7.0 10.7

Table V shows the effect of DAG and its sodium salt on barley and wheat. Height was measured after 41 days of ejection.

22 S € 919

Table V

Plant height, om 41 days after ejection barley wheat

Age of plants when treated, days. 28 10 28 10

Compound Composition Dosage kg a.i./ha DAG emulsifiable 6 51.5 41.5 62.8 42.5 concentrate "12 48.4 47-1 58.5 40.5

DAG

sodium water 6 45.4 43.4 46.6 37 * 5 salt water 12 32.9 55.9 33 * 6 25.0 Untreated - 48.6 47.6 6I.3 43 * 3 control The effect of DAG (as emulsifiable concentrate) in nitropyrrolidone on two shrub species is shown in Table VI. In the case of Carpinus hetulus, visual examination two months after the determination according to Table VI showed a stronger growth retardation effect than in Table VI. Fig. The amount of active ingredient in the solvent is shown in Table VI.

Table VI> 56919 23

Hedge height, cm, after 34 days of shower support

Thuja fastigiata. Carpinus Compound occidentalis betulus Untreated control 70 52 e DAG, 0.5 # 33 48 DAG, 1.0 # 25 15 DAG, 2.0 # 18 48 Effect of MG on apple trees and vines compared to the effect of two reference compounds, CCC and Alar , is shown in Table VIl ·

Table Over

Height, cm, weeks elapsed since treatment «» rt »11 Tll“ oa 9 TiU * ° *

Compound # a.i. apple vine Untreated - 25.4 21.4 control DAG 0.1 25.7 16.5 DAG 0.2 17.7 13.2 DAG 0.4 9.8 15.0 CCC 0.2 23.2 24.5

Alar 0.2 31.2 26.0 211 S6919 The effect of DAG Jin on the geranium and vines compared to the effect of the two reference compounds, CCC and Alar, is shown in Table VII.

Table Vili

Height, cm, 4 weeks after spraying Concentration a.i · p.p.m. DAG CCC

8000 16.0 13.6

4000 14.2 I3.O

2000 15.7 140 1000 15.9 14-4 500 17.1 17.2 250 19.4 16.4 Unprocessed control 20.0

Growth inhibition by Chrysanthemum morifolium

Table IX

Average lateral growth, length, cm, Compound Dosage p.p.m. 4 weeks after treatment DAG 3000 16.6 2000 17.8 a.

1000 19.3 500 17.9 250 18.0

Alar 4000 (a.i.) 17 · 3 untreated control —- 20.9

Table X shows the effect of DAG and reference compounds Ethrel on tomatoes as measured by plant height and flower number.

Table X

Tomato height, cm, 30 days after showering

Age of plants when sprayed, day 32 60

Compound Dosage ppm DAG 1000 25.7 52.3 4000 17.3 34 * 0

Ethrel 1000 (a.i.) 27.0 54-3 4000 (a.i.) 15.0 27.3 Processed - 34 · 3 56.7 Invalid control - 56919

Table X (continued)

Number of flowers 30 days after sun movement

Plant Age when sprayed, day. 32 60

Compound Dosage ppm.

DAG 1000 6.3 20.0 4000 2.3 8.7

Ethrel 1000 (ai) 3.7 15.0 4000 (ai) 3.0 0 Untreated control --- 6.8 5 * 0 Effect of DAG, ammonium salt of DAG and n-hutyl ester of DAG as a growth retardant on Bradilian pepper (Schinus terebinthifolius Raddi) and sumac wood (Rhus spp.) were studied. The leaves of the plants were sprayed until a gapless spray layer was obtained. Maintain CP-125 (a mixture of methyl 2-chloro-9-hydroxyfluorene-9-carboxylate, methyl 9-hydroxyfluorene-9-carboxylate and methyl 2,7-dichloro-9-hydroxyfluorene-9-carboxylate was used as reference substances. ). 43 days after spraying, notes are made of slowing or stopping growth, leaf fall and leaf deformation. * Table X1 shows the results in numbers. The rating scale was as follows: 0 - no effect 1 - height growth slowed 2 - height growth inhibited 3 - height growth inhibited and deformed leaves appear 4 - leaves completely fallen, new leaves are small and deformed.

56919 26

Ta «Iukko XI

Growth-regulating effect on Brazilian pepper and sumac tree After 43 days of treatment

Compound Concentration shower * »- Brazilian Sumac in solution Weapons pepper Untreated control - qq DAG 0.25 + $ 2 oil 0 0 DAG 0.5 + $ 2 oil 0 χ DAG 1.0 +2 io oil χ 2 DAG 1.0 q 2 DAG- ^ ammonium- 0.25 + 1 $> Triton JP 0 1 salt B-1956® "0.5 + 1 ϊ n χ 2" 1.0 + 1 $> "2 2 DAG-

n-butyl 0.25 + $ 2 oil 0 O

ester 0.5 + 2 # oil O 2 1.0 + 2 io oil χ 2 1.0 0 2

Maintain CF-I25 0.5 3 4

Triton ®B-1956 ® is a water-dispersible surfactant with a synthetic resin base, manufactured by Bohm & Haas. Maintain CF-125 is a mixture of methyl 2-chloro-9'-hydroxyfluorene-9-carboxylate, methyl 9-hydroxy-fluorene-9-carboxylate and methyl 2-7-dichloro-9-hydroxyfluorene-9-carboxylate.

oil excipient »Used in the above compositions is standard petrol, which is generally used in herbicidal compositions, especially when the herbicide is used to treat woody plants. This oil helps both the penetration of the active ingredient and its adhesion. The compositions of Table 27 56919 XI 'used emulsifiable non-phytotoxic spray oil,

Sun Oil 11E.

The herbicidal activity of DAG both alone and in combination with, for example, 2,4-D as a spray solution against several different species is shown in the following Table XII. Table XII. the figures refer to DAG spray solution, an emulsifiable concentrate in nitropyrrolidone. Figures show prevention compared to untreated plants.

§ 28 56919. φ

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1 1 2 SK 8 K K 8 8 £ S

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The herbicidal activity of 29 56919 MG, either alone or in combination with 2,4-D, was studied with Daucus' arota (wild carrot) sprayed with an emulsifiable concentrate in nitropyrrolidone. Table Vili shows epinastia- 4 and 18 days after spraying (epinastia is an unwanted growth in which parts of the plant bend outward and often grow downward). The results in Table XIH show that MG enhances the effect of 2,4-D *.

Table XIII

Compound Epinastia Dosage after 4 days after 18 days kg a.x./ha Untreated control 0 0 MG - 8 0 0 2,4-D (Na) - 1 15 50

MG + 2,4-D

8 + 1 80 95 8 + 0.5 80 80 4 + 1 90 90

Thus, according to the invention, the most preferred growth regulating compounds for use in heterbicidal preparations are 2,3: 6-di-O-isopropylidene-2-keto-L-gulonic acid (DAG), the corresponding sodium, potassium, ammonium, calcium and dimethylammonium salts. , as well as lower alkyl and lower alkynyl esters of these compounds, especially propargyl ester.

It was further found that when spraying a growth regulating preparation containing a compound of general formula I on fruit-bearing trees, it substantially reduces the force required to separate the fruit from the stem. This is obtained by comparison with untreated wood. It was further found that fruits harvested by the growth regulators of the invention were relatively free from wilting and spoilage.

The preparations according to the invention can be applied to fruit-bearing trees in liquid or solid compositions. Use can be on roots, stems, branches, leaves or fruits. The fruit drop preparations of the present invention can be sprayed or dusted, for example, from an airplane onto trees or introduced into the ground at the base of the trees so that the roots absorb them therefrom. The preferred method of use, which is also the most effective, is the application of preparations 3061919 as aqueous spray solutions. If desired, a composition based on a suitable organic solvent, such as an oily spray solution, may also be used.

In order to obtain the greatest effect in the use of normal fruit drop preparations according to the present invention, the preparation is preferably used, depending on the temperature, 1-2 weeks before the fruit is harvested. In areas where the possibility of rain between the use of the product and the harvest must be taken into account, a conventional fastening trough is suitably mixed into the product. Examples of such common fixing agents include glue, casein, salts of alginic acid, cellulose gum and the like, polyvinylpyrrolidone, invert syrup, corn syrup, etc.

The fruit drop preparations according to the invention contain compounds of the formula I as active ingredient. If desired, inert substances used in agriculture can be mixed in, especially if these substances act as wood treatment agents, and they can also be used in combination with known fruit drop agents. Such excipients also include, for example, surfactants, carriers, adhesives, stabilizers, etc.

The concentrations of the active compounds of the general formula I in the novel fruit drop agents according to the present invention vary, but it is necessary to use a sufficient amount to obtain the optimum effect. Thus, the aqueous spray solution contains from about 0.05 to about $ 1.5 (w / w) of active ingredient. The concentration naturally varies depending on the type of fruit and the size of the tree or shrub. The dosage is such that the harvest is really easier. In the case of spray solutions, the aqueous solution containing the fruit drop agent is sprayed so that the wood is covered with a gapless spray layer. This requires about JOO - about 9000 liters of diluted solution (about 0.1-1 wt.% Active ingredient) per hectare depending on the number and size of the trees to be treated.

To prepare a preferred spray aid solution containing a fruit drop agent according to the present invention, the active ingredient or a salt thereof is dispersed or dissolved in a carrier such as water. A surfactant may be added to the liquid spray solution from 0.1 to about 0.5% by weight of the carrier. Typical surfactants are Tritox®-B-1956, a water-dispersible resin-based surfactant preparation manufactured by Rohm & Haas. Furthermore, X-77 (Chevron-Ortho), a nonionic surfactant containing alkylaryl polyoxyethylene glycols, free fatty acids and isopropanol can be used.

31 56919

The fruit drop agents of the present invention affect the fall of fruit from many different fruit trees. Typical fruit trees of this kind are, for example, orange, grapefruit, olive, apple, cherry trees, etc. They also work in co-crops with other useful crops, such as cotton and soybeans (these cause leaf fall).

As already mentioned, fruit drop agents are sprayed on the trees as aqueous solutions.

The novel fruit disintegrant compositions of the invention containing 2,3,6,6-di-O-isopropylidene-2-keto-L-gulonic acid (known as DAG) are adjusted to a pH of 5-8 with a buffer, for example by adding potassium hydrogen sulphate to the aqueous solution. This buffering is necessary given the known instability of DAG in aqueous solutions with a pH below 5 ·

In those cases where the compounds used are insoluble in water, emulsifiable concentrates or wettable powder compositions are prepared from the active ingredient, which can be dispersed in water and thus form sprays.

DAG can be prepared as an emulsion concentrate using N-methyl-2-pyrrolidone or nitropyrrolidone as a solvent.

Wettable powders are prepared using an inert diluent, for example kaolin. A typical spray solution prepared from a wettable powder contains, for example, the active ingredient, from about 1% to about 5% of an inert diluent, minor amounts of dispersants, wetting agents and antifoams, and a corresponding and necessary amount of water.

Since oranges can be considered as typical fruits, the harvesting of which is facilitated by the use of chemical fruit drop agents, the effect of new fruit drop agents on orange trees is demonstrated.

Experiment with the sodium salt of 2,3, 6-di-O-isopropylidene-2-keto-L-gulonic acid as a fruit drop agent in citrus fruits, for example oranges. Aqueous solutions containing 0.05 #, 0.1%, 0.25%, 0.5% and 1.0% (w / w) of this sodium salt and 0.5% Triton B-1956 are prepared. These solutions are sprayed on Valencia orange trees, seedless bog grapefruit trees (SumpfgrapefTuite) and red grapefruit trees. One week after spraying, the only noticeable effect is a slight leaf fall on those trees treated with the higher dose. Two weeks after spraying, most oranges and grapefruits have fallen from trees treated with at least a 1 # dose.

About half of the fruit had fallen from the trees treated with the 0.5% dose and the fruit still in them was rather poorly attached.

32 5691 9

In addition to the fruit-dropping effect, the fruit also had a clear color enhancement, for example, a much deeper and darker color than untreated trees.

The sugar content and total solids content of the treated fruits were also increased compared to the untreated trees.

Similar results were obtained by spraying, for example, the ammonium salt or diethylammonium salt or n-butyl ester of 2,3-, 6-di-O-isopropylidene-2-keto-L-gulonic acid and 2,3-O-isopropylidene-β, 6-O-ethylidene Sodium salt of 2-keto-L-gulonic acid.

Whether the compounds of formula I are used as fruit drop agents or as pre-emergence or post-emergence herbicides, they can be prepared and formulated as described above and described below.

2,3: 1+, 6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate is a known commercial preparation which is an intermediate in the preparation of L-ascorbic acid.

It is prepared by oxidizing diacetone-L-sorbofuranose in an alkaline or neutral medium. Diacetone L-sorbofuranose is obtained by the reaction of L-sorbose with acetone in the presence of a strong acid.

The compounds used in the compositions of the present invention may be prepared a) by reacting the general formula r \

C-OH V

An acid according to S6919, wherein R1, R'g, R'g and R'4 have the same meaning as in formula II for the reaction in the presence of a base of the general formula

x-r5 VI

wherein X is chlorine, bromine or o-toluenesulfonic acid ester, and R 1. is straight chained or branched C 1-4 alkyl,

C8-C8-alkenyl, C8-C8-alkynyl or halo-lower alkyl; or b) if it is desired to prepare a compound of formula II wherein n is a number 2, reacting an acid of formula V in the presence of a base with a compound of general formula xrVx2 VI1 wherein X1 and Xg are chlorine, bromine or iodine and Rg is lower alkylene, or c) if it is desired to prepare a compound of formula II in which n is the number 2, the acid halide of the acid of formula V is reacted with a compound of general formula

HO-Rg-OH IX

with a diol of the formula wherein Rg is the same as in the formula VII, or d) in the case where it is desired to obtain a salt of the formula II in which n is the number 1 and R 'is ammonium; ammonium substituted with one or more C 1-4 alkyl or hydroxy-C 1-4 alkyl, the compound of general formula V is contacted with the general formula / R 7

N X

With a compound of formula R 9 wherein R 1, R 8 and R 6 are hydrogen, C 1-4 alkyl or hydroxy-C 1-6 alkyl or, when n is 2, with calcium hydroxide or magnesium hydroxide.

• Salts of 51-i 3.1 56919 DAG are prepared in the usual way. For this purpose, DAG is added to the aqueous base solution with vigorous stirring at room temperature.

In this event, the pH of the solution is maintained above 7. Upon completion of the reaction, excess water is removed under high vacuum. Anhydrous acetone (about 10 parts by volume) is then added until a syrup is formed and stirred overnight. The white crystalline precipitate formed is filtered off, washed with acetone and dried. In the case of non-volatile bases, equivalent amounts of acid are added. When volatile bases are used, for example ammonium hydroxide or dimethylamine, an excess of base is used and the unreacted excess is then evaporated in vacuo.

Since DAG is not stable under standard esterification conditions, such as esterification according to Fischer, the new esters of DAG are prepared by reaction with, for example, the corresponding C 1-6 alkyl, C 1-8 alkenyl or C 1-8 alkynyl halides under basic conditions at room temperature using inert organic solvents. , such as dimethylformamide (DMF). Esters are insoluble in water but soluble in methanol, acetone, ethanol, chloroform, pentane, benzene, ether, etc.

Although solutions consisting of a solvent and a compound of the invention are suitable for greenhouse experiments, they are not particularly useful for field experiments. Wettable powders are also not particularly useful because DAG derivatives must be solubilized in order to develop the necessary activity. Therefore, the acid is most preferably prepared as a soluble powder together with a buffering agent, because buffering the acid to pH 5-9 is essential. The acid can also be converted to an emulsion concentrate using N-methyl-2-pyrrolidone or nitropyrrolidone as follows: · ».

•. ζ 35 56919

Weight # of the entire composition MG 50

Atloz 2081B 4 N-methyl-2-pyrrolidone or nitropyrrolidone 46

Atlox 2081B is a mixture of polyoxyethylene sorbitan esters of fatty acids and acidic resins as well as alkylaryl sulfonates.

The salts are water soluble and do not require any particular formulation.

The MG esters are formulated as emulsifiable concentrates with a xylene base, which can then be mixed with water. Emulsions can be prepared from these concentrates containing up to 23-50% by weight of active ingredient. The following are typical emulsifiable concentrates of MG esters.

Weight- # of the entire mixture

Active substance 25 50

Xylene 71 46

Atlox 3405 2

Atlox 3404 2

Smulphor SL 620 - 2

Drivnrolse GMC-8 - 2

Atlox 3403 is a mixture of polyoxyethylene ethers, polyoxyethylene glycerol and alkylarylsulfonate.

Atlox 3404 is a mixture of polyoxyethylene alkylaryl ether and alkylarylsulfonate.

Smulphor SL 620 is a polyethylated vegetable oil.

Drewmulee GMC-8 is a low molecular weight saturated coconut fatty acid monoglyceride.

A concentrated solution of sodium 2,3,3,4-di-O-isopropylidene-2-keto-L-gulonate (95 wt.%) And sodium dioctyl sulfosuccinate (5 wt.%) Is prepared and spray dried. This gives a wettable powder which is completely water soluble.

In another embodiment, finely divided sodium 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate is mixed with pumice grains. To this dry mixture is added 10 # by weight of the mixture of water. A portion of the sodium salt of 2,3,4-((4,4-O-isopropylidene-2-keto-L-gulonic acid) is then soluble and serves as a means of removing the remaining insoluble sodium 2,3,4,4-di-O-isopropylidene-2- to bind keto-L-gulonate by pumice granule.

36 S6919

In another embodiment, an equimolar amount of diethanolamine is added with stirring to an aqueous solution of 2,3,6,6-di-O-isopropylidene-2-keto-L-gulonic acid. A clear solution is obtained, the pH of which is adjusted to 8 by dropwise addition of diethanolamine.

In another embodiment, ammonia (25%, equimolar amount) is added to an aqueous solution of 2,3: 1,3-di-O-isopropylidene-2-keto-L-gulonic acid. A clear solution is obtained, the pH of which is adjusted to 8 by dropwise addition of ammonia (25%).

Those compounds of the formula I in which R 1 and R 2 or R 2, R 2 and R 2 mean other than methyl also show a pre-emergence and a post-emergence growth-regulating effect. For example, 2,3: 6,6-di-O-butylidene-2-keto-L-gulonic acid at a dose of 8 kg / ha used as a pre-emergence growth regulator completely inhibits the growth of Amaranthus species after 20 days and causes a germination-after-growth regulator strong growth loss of red beans. 2,3,6-di-O- (3-pentylidene) -2-keto-L-gulonic acid at a dose of 8 kg / ha as a germination-after-growth regulator causes severe growth retardation in Amaranthus species, Brassita kaber, Ipomea species and red beans.

Compounds in which the U, 6-O-isopropylidene group has been replaced by another group are prepared by the so-called "Ketaalivaihtoreaktiossa". For this purpose, the DAG is dissolved in the desired ketone, aldehyde, ketal or acetal and an acid catalyst is added. These compounds can be prepared using a similar ketal exchange reaction using 2,3, β-di-O-isopropylidene-of-L-sorbofuranose as the starting material and then oxidizing the product obtained.

The ketones and aldehydes that can be used in the preparation methods are of the general formula 0 R10-11, wherein R1q is, for example, methyl or ethyl, and R1 is methyl or ethyl. Typical such compounds are, for example, diethyl ketone or methyl ethyl ketone. Ketones in which both the radicals R 2 and R 2 are quite large have not proved to be particularly advantageous, since these residues are a steric hindrance in the reaction. When an asymmetric aldehyde or ketone is used, the bulky part in the exo position (R in formula I) after the reaction has taken place and causes a new center of asymmetry.

• W '37 56919

Any strong oxygen can be used as a catalyst. The preferred catalyst is perchloric acid. Other representatives of such acids include sulfuric acid, hydrochloric acid, p-toluenesulfonic acid, methanesulfonic acid and trifluoromethanesulfonic acid.

The preferred temperature range for this reaction is about -20 to about 30 °, and a particularly preferred range is 20 to 30 ° (room temperature). At the same time, the decomposition point of MG is the upper limit to which the reaction mixture can be heated »For this reason, the reaction mixture can be heated. Therefore, the reaction mixture is not heated above 100 °.

Compounds in which both isopropylidene groups have been replaced by other groups are prepared starting from sorbose according to the method described by Reichtein and Griissner. Chim. Aota, 17, 311 (1934.) 7 conditions. In this process, a suitable ketone or a suitable aldehyde is reacted at room temperature or below with L-sorbose using a strong acid such as sulfuric acid as a catalyst. The intermediate thus obtained is then oxidized in an alkali or neutral reaction medium.

In the preparation of di-O-alkylidene sorbofuranose, perchloric acid, hydrochloric acid, p-toluenesulfonic acid, etc. are preferably used as the acid catalyst, with sulfuric acid being particularly preferred.

Since the reaction takes place exothermically, work is carried out at or below room temperature, with a particularly preferred temperature range being about 0 ° to about -20 °.

In the subsequent acid preparation of the sorbofuranose intermediate, oxidation is carried out in a neutral or alkaline medium using, for example, sodium permanganate, potassium bichromate, potassium permanganate / potassium hydroxide or sodium hypochlorite-2 + ti / Ni as the oxidizing agent. Both of the latter oxidizing agents are most preferred. The oxidation can also be carried out by catalyst inhibition using palladium or platinum and oxygen.

A suitable temperature range is between room temperature and 100 °, with a range of 50-60 ° being particularly preferred.

For example, 2.3 s of 4 ♦ 6-di-O-isopropylidene-2-keto-L-gulonic acid were prepared according to the above-mentioned Helv. Chim. Instructions provided by Acta.

The following examples illustrate the preparation of compounds of formula I.

Example 1

Ethyl 2,3: 4,6-di-0-isopropylidene-2-keto-L-gulonaatti.

To a solution of 100 g of anhydrous potassium carbonate in 9 to 6 ml of dimethylformamide is added, with stirring at room temperature, 292.2 g of 38 S 2,319 2,3: 4 * 6-di-O-isopropylidene-2-keto-L- gulonic acid monohydrate (MG monohydrate) and then 203 δ ethyl iodide. Stirring is continued at room temperature for 24 hours. The mixture is then filtered to remove inorganic salts and the dimethylformamide is removed by distillation in vacuo (about 60 ° and about 10 Torr). Add 200 mL of acetone to dissolve the remaining ether. Insoluble inorganic salts are filtered off. The filter cake is washed with 100 ml of acetone. The filtrate is added to the ester-containing solution. The solvent is evaporated in vacuo to about 300 nothing and the crude product is isolated by cooling this solution to 5 °. The crude product is recrystallized from methanol / acetone to give 284 δ of ethyl 2,3-t4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 99 to 100.5 ° C.

According to this generally applicable process, starting from 2,3: 4> 6-di-O-isopropylidene-2-keto-L-gulonic acid and 1,2-dibromoethane in a molar ratio of 2: 1 bis-ester: bis-2,3: 4,6-di-0-isopropylidene-2-keto-L-gulonaattietyleeniglykoliesteri.

Example 2

Methyl 2,3i4 »6-di-0-ieopropylideeni-2-keto-L-gulonaatti

To a suspension of 100 g of anhydrous potassium carbonate in 946 ml of dimethylformamide is added, with stirring, 292.2 g of 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate (MG monohydrate), then 203 g are added to the solution. Methyl iodide. The mixture is stirred for 4 hours at room temperature, then filtered to remove inorganic salts. Dimethylformamide is distilled off in vacuo.

To the residue is added 200 ml of acetone to dissolve the ester. Insoluble inorganic salts are again removed by filtration. The filter cake is washed with 100 ml of acetone. The filtrate is combined with the ester solution, then evaporated in vacuo to a yellow syrup which, after standing for some time, crystallizes as large prisms. Vacuum distillation at 127-129 ° and 0.35-0.37 Torr'iesa gives 268 g of a colorless liquid which solidifies on standing · Methyl-2,3 * 4,6-di-O-isopropylidene-2-keto-L gulonate melts 46.5-47.5 °.

Example 3 n-Butyl 2,3,3,4,6-di-O-isopropylidene-2-keto-L * gulonate

To a suspension of 100 g of anhydrous potassium carbonate in 946 ml of dimethylformamide is added with stirring 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonic acid monohydrate (292.2 g) and then 197 g of n-butyl iodide . The mixture is stirred at room temperature for 46 hours, then the inorganic salts are filtered off. Dimethylformamide is removed by vacuum distillation. 200 ml of acetone are added to the residue, and the inorganic salts still present are removed by filtration. The filter cake is washed with 100 ml of acetone * The filtrate is combined with the ester solution and evaporated in vacuo. Recrystallization of the residue from methanol-acetone gives 172 g of colorless crystals of n-butyl 2,3,4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 55.9-56.8 °.

Example 4 n-Propyl 2,3-4,6-di-O-isopropylidene-2-keto-L-gulonate n-propyl 2,3,4,4,6-di-O-isopropylidene-2-keto-L-gulonate is prepared analogously to the methods described in Examples 1-3 using 200 g of 1-bromopropane as the halide. Yield 150.6 g, melting point 80-81 ° C.

Example 5 n-Pentyl 2,3,4,4,6-di-O-isopropylidene-2-keto-L-gulonate n-Pentyl 2,3,4,4-di-O-isopropylidene-2-keto-L-gulonate is prepared analogously to the working instructions of Examples 1-3 using 300 g of 1-bromopentane as the halide in the reaction. Yield 503 δ »boiling point 195 C / 0.5 Torr.

Example 6 n-Dodecyl-2,3,4,4-di-O-isopropylidene-2-keto-L-gulonate n-Dodecyl-2,3,4,6-di-O-isopropylidene-2-keto-L gulonate is prepared analogously to the working instructions of Examples 1-3 by reacting 100 g of 1-bromidodecane as a halide. Yield 75 δ after two recrystallizations from ethanol. Melting point 10.5 ° C.

Example 7

Allyl 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate Allyl 2,3,3,4,6-di-O-isopropylidene-2-keto-L-gulonate is prepared analogously to Examples 1. -3 according to work instructions using 133 δ allyl bromide »Yield 282 g. Melting point 95-95.5 ° C.

Example 8

Isopropyl 2,3,4,6-di-O-isopropylidene-2-keto-L-gulonate Isopropyl 2,3 * 4,6-di-O-isopropylidene-2-keto-L-gulonate is prepared analogously to Examples 1-3 by reacting 250 g of 2-bromopropane according to the instructions. Yield 116.8 g, melting point 107.5-109 ° C »

Other straight-chain and branched alpha-hydrocarbon and halo-lower alkyl esters can be prepared in a similar manner.

56919

Example 9

Sodium 2,3-O-isopropylidene-4,6-O-ethylidene-2-keto-L-gulonate 48 g of 2,3,4,4-di-O-isopropylidene-2-keto-L-gulonic acid (DAG) are dissolved To 250 g of paraldehyde. 5 drops of $ 70 perchloric acid are then added and then the reaction is allowed to proceed for 12 days at room temperature with continuous control by thin layer chromatography or gas-liquid chromatography. The solution is then added with vigorous stirring to 16.8 g of sodium bicarbonate slurried in 100 ml of water. Excess paraldehyde and excess water are distilled off in vacuo. The residue is recrystallized from an alcohol / water mixture to give 50.4 g of sodium 2,3-O-isopropylidene-4,6-ethylidene-2-keto-L-gulonate. Physico-chemical figures (nuclear resonance spectrum, mass spectrum, infrared spectrum) show the structure next \ ^ ^ COONa 0 o '

Other 2,3-O-isopropylidene-4,6-O- (R 1 -R 2) -2-keto-L-gulonic acids (structure i) can also be prepared as described above, wherein the R 1 and R 2 substituents represent straight-chain or branched lower alkyl.

Example 10 2,3-O-Isopropylidene-4- [6-O- (3-pentylidene) -2-keto-L-gulonic acid 29 # 2 g of MGs are dissolved in 300 ml of diethyl ketone. 3 drops of $ 70 perchloric acid are added and the reaction is allowed to proceed for 72 hours at room temperature. 30 »3 g of crude product are obtained. Purification by recrystallization from chloroform / hexane gives white leafy crystals, m.p. 129.8-130.2 ° C.

41 '56919

Example 11 2,3-O-Iropropylidene-4,6-O- (2-t-butylidene) -2-keto-L-gulonic acid 29.2 g of DAG are dissolved in 500 ml of methyl ethyl ketone, and 5 drops of 70 ? S of perchloric acid. The reaction is allowed to proceed at room temperature for 72 hours. 57.6 g of crude product are obtained. Recrystallization from chloroform / hexane gives the free acid *

Analysis calculated for the formula Ο ^ Ι ^ Ο ^: C 50.97 H 7.24 E ^ O 5.96 Found: C 51.09 H 7.46 HgO 6.20

Example 12 2,3: 4,6-Di-O- (3-pentylidene) -2-keto-L-gulonic acid To 495 ml of diethyl ketone is added dropwise while cooling to 0 ° 81 g of sulfuric acid and then 120 g of L-sorbose . The reaction is allowed to proceed for 2 days with stirring at -10 to -20 °. The mixture is then neutralized with 600 ml of 10 # sodium hydroxide solution and the excess diethyl ketone is distilled off in vacuo. 2,3: 4,6-di-O- (3-pentylidene) -er-L-sorbofuranose is isolated by extraction with toluene.

31.6 g of 2,3: 4,6-di-O- (3-pentylidene) -oc-L-sorbofuranose recrystallized from pentane are heated for 4 hours at 50-60 ° together with potassium hydroxide (23.8 g). and potassium permanganate (15.8 g) in water (250 ml). An additional 15.9 g of potassium permanganate is then added and the reaction mixture is stirred without heating overnight. The mixture is filtered, evaporated to 150 ml, cooled to -5 ° and then adjusted to pH 3.0 with concentrated hydrochloric acid. The precipitate formed is filtered off and washed with water. 26.8 g of 2,3: 4,6-di-O- (3-pentylidene) -2-keto-L-gulonic acid with a melting point of 144-145 [deg.] C. are obtained by hand. Other gulonic acid derivatives can be prepared in a similar manner. R ', R_, R_ and H. denote a straight-chain or branched lower 22 5 4 alkyl group.

Example 13 2,3: 4,6-Di-O- (2-butylidene) -2-keto-L-gulonic acid hydrate 2,3: 4,6-di-O- (2-butylidene) -2-keto-L -gulonic acid hydrate is prepared according to the procedure described in Example 15 using methyl ethyl ketone in the reaction. The product, when recrystallized from hexane / chloroform, melts at 96.5-103 ° C.

Example 14 2-Chloroethyl 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate 6 g 2,3: 4,6-Di-O-isopropylidene-2-keto-L-gulonic acid (anhydrous) is dissolved in 14 ml of pyridine and 3.2 ml of methylene chloride, and 3.2 ml of thionyl chloride are added dropwise to the solution under stirring and ice-cooling.

V.

1.2 56919 After 3 hours at room temperature, 5 ml of 2-chloroethanol are added to the reaction mixture and then stirred for a further 3 hours. The reaction solution is then extracted with methylene chloride and washed successively with ice-cold 2N hydrochloric acid, 2N sodium hydroxide and water, the organic phase is dried over sodium sulfate and evaporated to dryness. The residue is purified on a silica gel column and then distilled. 5 g of an oily product are obtained, b.p. 88 ° C / 0.01 Torr.

In analogy to the above examples, especially according to Examples 1-3 and 14, the following compounds can be prepared: allyl 2,3: 4T6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 94.5-95 ° C, potassium 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. > 300 ° C, ammonium 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 177 »5-178.5 ° C, calcium 2,3 * 4,6-di-O-ieopropylidene-2-keto-L-gulonate, m.p. 265-267 ° C, dimethylammonine 2,3-4-di-O-isopropylidene-2-keto-L-gulonate, m.p. 155-165 ° C, N-ethanolammonium 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 208-209 ° C, methyl 2,3 * 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 46- 5-47.5 ° C, ethyl 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 99-105 ° C, n-butyl 2,3-4 * 6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 54-57 ° C, 3-chloropropyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 130 ° C / 0.005 Torr, n-hexyl-2,3: 4,6-α-O-isopropylidene-2-keto-L-gulonate, n = 1.4544, n-heptyl-2,3,4,4 6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 102-103 ° C / 0.01 Torr, n-octyl-2,3,4,4-di-O-isopropylidene-2-keto-L-gulonate, mp 1.4538, n-nonyl-2,3: 4-di-O-isopropylidene-2-keto-L-gulonate, n ': 1.4548, n-undecyl-2,3: 4,6-di-O-isopropylidene-2-keto-L gulonate nf: 1.4555, 2,2,2-trichloroethyl 2,3: 4 * 6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 65-66 ° C, n-dodecyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 10.5 ° C, n-propyl 2,3,3,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 80-81 ° C, 1-propyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 107.5-109 ° C, n-Decyl-2,3 * 4,6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 193 ° C / 0.5 Torr, 2-chromoethyl 2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 157 ° C / 0.1 Torr, 1.3 S G 919

2-butyl 2,3-4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 5 to 96.5 * 95 ° C

1-amyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 135 0 / 0.1 Torr, t-butyl 2,3-4,6-di-O-isopropylidene-2-keto-L-gulonate, 2-pentynyl 2,3-4,6-di-O- isopropylidene-2-keto-L-gulonate, 1-hexyn-3-yl-2,3 * 4,6-di-O-isopropylidene-2-keto-L-gulonate, 3-methyl-1-butyn -3-yl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, 5-hexenyl-2,3: 4,6-di-O-isopropylidene-2-keto-L -gilortate, 3-pentyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, dichloromethyl-2,3 * 4,6-di-O-isopropylidene-2-keto-L -gulonate, 2,2-dichloroethyl-2,3: 4 * 6-di-O-isopropylidene-2-keto-L-gulonate, 2-chloroethyl-2,3: 4,6-di-O-isopropylidene-2-keto -L-gulonate, 4-chlorobutyl-2,3 * 4,6-di-O-isopropylidene-2-keto-L-gulonate, 2,2,2-trifluoroethyl-2,5 * 4,6-di-O-iopropylidene 2-Keto-L-gulonate, 2-fluoroethyl-2,3 * 4,6-di-O-iso-propylene-2-keto-L-gulonate, 2-bromo- 1,1,2,2-tetrafluoroethyl-2,3: 4,6-di-O-iopropylidene-2-keto-L-gulonate, 2,2,3,3,4,4,4-heptafluorobutyl-2, 3: 4,6-di-0-isopropylidene-2-keto-L- gulonate, 2,2,3,3,4,4,5,5-octafluoropentyl-2,3 * 4,6-di-O-iopropylidene-2-keto-L-gulonate, sodium 2,3: 4-6-di-O-isopropylidene-2-keto-L-phosphonate, m.p. > 300 ° C, 2-propynyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, m.p. 91.5-92.5 ° C, n-pentyl-2,3: 4,6-di-O-isopropylidene-2-keto-L-gulonate, b.p. 195 ° C / 0.1 Torr,

Claims (3)

56919 1 + 4 A preparation for controlling plant growth, characterized in that it contains, in addition to the usual carriers, as active ingredient a sufficient amount of one or more compounds of the general formula --R.XHgO IO / 1 * 2 In, in which, when n is 1, R is hydrogen; sodium; potassium; ammonium; ammonium substituted with one or more C 1-4 alkyl or C 1 -C 4 hydroxyalkyl; C ^ C ^^ - alkyl; Cg-Cg alkenyl; C 8 -C 8 alkynyl or halo-lower alkyl; and when n is 2, R is calcium, magnesium or lower alkylene, R 1, R 8, R 6 and R 4 are hydrogen or C 1 -C 4 alkyl, n is a number 1 or 2, and X is a number 0 -1; as an enantiomer or racemic mixture. Preparation according to Claim 1, characterized in that it contains, as active ingredient, sodium 2,3: 1+, 6-di-O-isopropylidene-2-keto-L-gulonate. Preparation according to Claim 1, characterized in that it contains N-ethanolammonium 2,3: 1,6-di-O-isopropylidene-2-keto-L-gulonate as active ingredient.