JPS63196572A - Tetrahydropyrimidine derivative and plant growth retardant - Google Patents

Abstract

NEW MATERIAL:A tetrahydropyrimidine derivative expressed by formula I [R<1> and R<2> are alkyl, halogenated lower alkyl or (substituted) phenyl; R<3> is lower alkyl; R<4>-R<8> are H, halogen or lower alkyl]. EXAMPLE:4-Butyl-N-( 2, 6-diethylphenyl )-1,4,5,6-tetrahydro-6-hydroxy-2,6-dimethyl- 5-pyrimidinecarboxamide. USE:An active ingredient of plant growth retardants. PREPARATION:An alpha,beta-unsaturated carbonyl compound expressed by formula II is reacted with an amidine compound expressed by formula III in an inert solvent, such as ethanol, etc., to afford the compound expressed by formula I.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a novel compound belonging to 2.4.6-doli-substituted pyrimidine-5-carboxylic acid anilide and a plant growth inhibitor.

(Prior art) Conventionally, compounds belonging to pyrimidine-5-carboxylic acid anilide have been classified as J, Chem, So.
c,) 1965.6695 and JP-A-61-43173
Those listed in the number are known. However, these compounds differ from the compounds of the present invention in that a nitrogen atom is bonded to the 2-position of the pyrimidine ring.
), the 2nd, 4th, and 6th positions of the pyrimidine ring
A pyrimidine-5-carboxylic acid anilide derivative in which all of the substituents at positions have carbon-carbon bonds with the carbons forming the pyrimidine ring has never been known.

(Object and Structure) The present invention provides a novel tetrahydropyrimidine derivative represented by the following formula (I>).

(In the formula, R1 and R2 are the same or different, an alkyl group,
Halogenated lower alkyl group or optionally substituted phenyl group; R3 is lower alkyl group; R4, R5, R6,
R7 and R8 are the same or different and are a hydrogen atom, a halogen atom, or a lower alkyl group).

The present invention also provides a plant growth inhibitor containing at least one of the above compounds as an active ingredient.

In the compound of formula (I) above, the alkyl group means a straight chain or branched hydrocarbon group having 1 to 12 carbon atoms,
Methyl, ethyl, propyl, isopropyl, butyl, isobutyl, secondary butyl, pentyl, isopentyl, 1
-Methylbutyl, 1-ethylpropyl, hexyl, octyl groups, etc.

The halogenated lower alkyl group includes trifluoromethyl,
difluoromethyl, fluoromethyl, chloromethyl, 2
-Chloroethyl, 3-chloropropyl, 2-bromoethyl, 4-chlorobutyl, and the like.

The phenyl group in R1 and R2 includes an unsubstituted phenyl group, a halogen atom, a cyano group, a nitro group, an amino group, a lower alkyl group, a halogenated lower alkyl group,
Included are hydroxy groups, phenyl groups substituted with 1 to 3 lower alkoxy groups, and the like.

Examples of lower alkyl groups include alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl,
Examples include isopentyl.

Halogen atoms include chlorine, bromine, fluorine and iodine.

Lower alkoxy groups include methoxy, ethoxy, propoxy and the like.

The compound of formula (I) of the present invention also forms addition salts with acids such as hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, para-toluenesulfonic acid, and trifluoroacetic acid. Such addition salts are also included within the scope of this invention.

The compound of formula (I>) of this invention can be produced, for example, by the method shown below.

A tetrahydropyrimidine derivative (I) can be obtained by reacting an α,β-unsaturated silvonyl compound represented by formula (II>) with an amidine compound (In) in an inert solvent such as ethanol or methanol. When using a salt such as a hydrochloride, it is preferable to form it into a free form with an alkali metal alkoxide in advance.

(Blank below, continued on next page) (II) (Ill) (I) ■ (rV) (■tsu (V) R6, R7, Re represent the same meanings as defined in formula (I>) Like this The tetrahydropyrimidine derivative (I) obtained by heating with an acid such as P-toluenesulfonic acid or benzenesulfonic acid, or with an inorganic substance such as alumina, silica or molecular sieve at 120 to 200°C, or When dehydrated by heating under reflux in the presence of phosphorus oxychloride, a dihydropyrimidine derivative represented by formula (IV) or (IV') is obtained.
IV) and (IV') are tautomers.

This dihydropyrimidine derivative (IV) or (IV'
), manganese dioxide, sulfur, 2,3-dichloro-5
The compound (
V) can be obtained.

The compound of formula (V) of the present invention can also be prepared by adding a compound of formula (V) to a hydroperoxide such as hydrogen peroxide, t-butyl hydroperoxide, peracetic acid, perbenzoic acid, m- 1-oxide or 3-oxide compounds are obtained by treatment with an oxidizing agent such as an organic peracid such as chloroperbenzoic acid.

In the plant growth inhibitor of the present invention, the tetrahydropyrimidine derivative represented by formula (I>) may be used as an active ingredient as it is, but it is generally combined with a solid carrier, liquid carrier, surfactant, or other formulation auxiliary agent. They are mixed and formulated into wettable powders, granules, emulsions, etc. These preparations contain the compound of the present invention in an amount of 10 to 80% for wettable powders, 2 to 20% for granules, and 10 to 50% for emulsions. (all percentages are shown by weight).Solid carriers used in the formulation include kaolin, bentonite, clays, talc, diatomaceous earth, gicrite, zeolite, pyrophyllite, synthetic oxidized There are fine powders or granules such as silicon and calcium carbonate,
Liquid carriers include aromatic hydrocarbons such as xylene and methylnaphthalene, alcohols such as ethanol, isopropanol, ethylene glycol, and methyl cellosolve, ketones such as acetone, irophorone, and cyclohexanone, and vegetable oils such as soybean oil and cottonseed oil. , dimethylformamide, dimethylsulfoxide, acetonitrile, water, etc. Surfactants used for dispersion, emulsification, etc. include polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene rubitan fatty acid ester, polyoxyethylene Examples include nonionic surfactants such as polyoxypropylene block polymers, and anionic surfactants such as alkyl sulfate salts, alkyl sulfonate salts, alkylaryl sulfonate salts, and polyoxyethylene alkyl sulfate salts.

Formulation adjuvants include lignin sulfonates, alginates, polyacrylates, polyvinyl alcohol, vegetable gums, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (NEC), and the like.

The wettable powders and emulsions prepared as described above are usually diluted with water, and the granules can be used as they are by spraying on the soil or, alternatively, spraying on foliage and soil.

The plant growth inhibitor of the present invention may be used in combination with other plant growth inhibitors, insecticides, nematicides, fungicides, fertilizers, or soil conditioners, if necessary.

Hereinafter, the present invention will be explained by examples. Table 1 shows the characteristic values of the compounds mentioned in the examples, and Table 2 shows the growth-inhibiting effect of the plant growth inhibitor of the present invention on plants.

The method for measuring the plant growth inhibitory effect is as follows.

Talc (50 parts by weight), bentonite (25 parts by weight),
A carrier was prepared by mixing Sorbo-Rue 9047 (manufactured by Toho Chemical Co., Ltd., 2 parts by weight) and Sorbo-Rue 5039 (manufactured by Toho Chemical Co., Ltd., 3 parts by weight). A 20% wettable powder was prepared by mixing 50 parts by weight of the test compound and 200 parts by weight of the carrier.

This hydrating powder was dispersed in pure water to obtain a hydrating powder dispersion having a predetermined concentration. Separately, petri dishes in which seeds of rice, Japanese millet, and Japanese radish were germinated were prepared, the above-mentioned hydrating agent dispersion was added, and the seedlings were grown for 7 days in a constant temperature warehouse with lighting at 25° C., and the degree of growth was observed. How to display the results: 1 = no effect, 2-25% growth inhibition, 3 = 50% growth inhibition, 4 = 75% growth inhibition, 5
= complete withering.

Example 1 A mixture of 2.339 (10 mn+ol) of N-(2,6-dinitylphenyl)-3-oxobutyric acid amide, 1.12 g (13 mmol) of pentanal, 2 drops of piperidine, and 1011 t1 of methylene chloride was stirred for 5 hours under water cooling. Thereafter, it was allowed to stand at 4 to 5°C for 2 days. After the produced water was removed with anhydrous sodium sulfate, the solvent was removed by drying using a vacuum bottom-tally evaporator to obtain a residue.

On the other hand, acetamidine hydrochloride 0% in absolute ethanol 50%
．． 959 (10 Dragon 01) was dissolved, 0.689 (10 uol) of sodium ethylate was added at room temperature, and the mixture was stirred for 1 hour to prepare an acetamidine solution.

The residue obtained earlier was mixed with 40 d of ethanol and 10 M of water.
Dissolve in a mixture of and add this to the acetamidine solution,
Stirred at room temperature for 1 hour. Ethanol was distilled off under reduced pressure, saturated brine was added, and extraction with methylene chloride was performed. After removing the solvent, crystallization from ethyl acetate yields 4-butyl-N-(2,
1.049 of compound N0.1> was obtained.

Melting point: 261-270℃ IR (KBr disk): 1632,1665ca-
'NMR(CDCl2>δ value 0.60-2.10(m
, 9H) , 1.18 (t, 6H) , 1.48 (s
, 3H) , 1.92 (s, 3H) , 2.10~2
．． 90 (m, IH), 2.63 (q, 4H), 3
．． 40-4.20 (m, IH), 6.97-7゜3
0 (m, 3H) Examples 2 to 4 The following compounds were obtained from the corresponding β-ketoamide derivatives and aldehydes in the same manner as in Example 1.

N-(4-bromo-2,6-dinitylphenyl)-4-
Butyl-1,4,5,6-tetrahydro-6-hydroxy-2,6-dimethyl-5-pyrimidinecarboxamide (Example 2, Compound No. 2) N-(2,6-dinitylphenyl)-1,4゜5 .6-Tetrahydro-6-hydroxy-2,4-dimethyl-6-pentyl-5-pyrimidinecarboxamide (Example 3, Compound No., 3>N-
(2,6-dinitylphenyl)-1,4°5.6-tetrahydro-6-hydroxy-2,4-dimethyl-6-proyl-5-pyrimidinecarboxamide (Example 4, Compound No. 4>Example 5 N 9.33 g (40 m
mori, benzua, rudehyde 4.20g (40mmo
A mixture of 0, 2 rni of piperidine, 0.5 d of acetic acid, and 40 d of benzene was heated and refluxed for 2 hours while removing by-produced water. The reaction mixture was washed successively with 1N acid, water, and saturated sodium bicarbonate solution, and then the solvent was removed under reduced pressure to leave a residue. □ Meanwhile, 200 rI of absolute ethanol! To this solution, 3.78 g of acetamidine hydrochloride was dissolved in 3.1 g of acetamidine hydrochloride, 2.72 g of sodium ethylate was added at room temperature, and the mixture was stirred for 1 hour to prepare an acetamidine solution.

The residue obtained earlier was dissolved in 400 WJl of ethanol,
This was added to the acetamidine solution and stirred at room temperature for 1 hour. Ethanol was distilled off under reduced pressure, saturated brine was added, and extraction with methylene chloride was performed. After removing the solvent, crystallization from a mixture of ethyl acetate and hexane yields N-(2,6-dinitylphenyl)-1°4.5.6-tetrahydro-4-hydroxy-2°4-dimethyl-6-funinyl. -5-pyrimidinecarboxamide (compound No. 5> is 6.65 g
Obtained.

IR (KBr' disk): 1622.1670 cm-1 NMR (CDCl2-DMSO-d,) δ value: 0.92
(t, 6H), 1.68 (s, 3H), 1.80
-2.40 (m, 5H), 2.04 (s.

3H>, 3.30-4.00 (m, IH), 6°80-7.60 (m, 8H)

Claims (4)

[Claims] (1) Formula (I): ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1 and R^2 are the same or different and are an alkyl group, a halogenated lower alkyl group, or a substituted Good phenyl group; R^3 is lower alkyl group; R^4, R^
5. A tetrahydropyrimidine derivative in which R^6, R^7, and R^8 are the same or different and each is a hydrogen atom, a halogen atom, or a lower alkyl group. (2) Claim No. (1) in which R^3 is a methyl group
Tetrahydropyrimidine derivatives described in . (3) There are ▲mathematical formulas, chemical formulas, tables, etc. for formula (I)▼
is 2,6-diethylphenyl group or 4-bromo-2
, 6-diethylphenyl group
) and the tetrahydropyrimidine derivative described in (2). (4) Formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R^1 and R^2 are the same or different and are an alkyl group, a halogenated lower alkyl group, or a substituted Good phenyl group; R^3 is lower alkyl group; R^4, R^
5. A plant containing as an active ingredient at least one type of tetrahydropyrimidine derivative represented by a hydrogen atom, a halogen atom, or a lower alkyl group, where R^6, R^7, and R^8 are the same or different; Growth inhibitor.