JPH07242590A - Abscisic acid derivative - Google Patents

Abstract

PURPOSE:To obtain a compound having growth-inhibiting activity of plants and long-term germination-inhibiting activity of plants and useful as a plant growth regulator. CONSTITUTION:An abscisic acid derivative is expressed by formula I. The compound of formula I is obtained by reacting a compound of formula II with N-bromosuccinimide and benzoylperoxide and then, reacting the reactional product with quinoline, adding rose bengal thereto, stirring these substances under oxygen atmosphere, dissolving a reacted liquid in methanol, absorbing the solution into a basic alumina, suspending the liquid in hexane to give a compound of formula III, adding 1N sodium hydroxide aqueous solution to the compound of formula III, stirring the liquid and separating the abscisic acid derivative. Abscisic acid is a sort of plant hormone and retains storing and life-prolonging effect of seeds and nutrient growth period of a plant and yield-increasing effect on plants can be expected by the abscisic acid derivative.

Description

Detailed Description of the Invention

[0001]

This invention relates to abscisic acid derivatives.

2. Description of the Related Art Abscisic acid, a kind of plant hormone, forms dormant buds,
In addition to organ detachment, various useful plant physiological phenomena such as stomatal closure under water stress conditions, low temperature tolerance, growth suppression and promotion, fruit setting and ripening, aging, root gravitropism, and flowering It is known to be involved in expression. Therefore, application of abscisic acid is expected to enable various plant growth regulators, and attempts have been made to apply it as a plant growth regulator such as a seed life-prolonging agent and a crop yield enhancer. Since it does not last, its efficacy as a plant growth regulator is not always sufficient and it has not been put to practical use.

[0002]

SUMMARY OF THE INVENTION In view of such circumstances, the present inventors have made earnest studies on an abscisic acid derivative, and as a result,

[Chemical 2] The present invention was completed by discovering that the abscisic acid derivative represented by the formula (3) has an excellent plant growth regulating action. That is,
The present invention provides an abscisic acid derivative represented by the formula (2) (hereinafter referred to as the compound of the present invention). The compound of the present invention has two asymmetric carbon atoms, and there can be a total of four optical isomers (R, S), but the present invention includes each optical isomer and a mixture thereof in any ratio. . Further, the geometric isomerism of the double bond at the 4-position (the carbon of the carboxyl group is the 1-position) of the compound of the present invention is E, but the double bond at the 2-position (the carbon of the carboxyl group is the 1-position) is For geometric isomerism, each of E and Z and mixtures thereof in any ratio are included in the present invention.

The compound of the present invention can be produced, for example, according to the following formula.

[Chemical 3] [In the formula, NBS represents N-bromosuccinimide,
BPO stands for benzoyl peroxide. ] In the above-mentioned formula 3, the compound 1 as a starting material is
Org. Chem., 56 , 1718-1725 (1991).

When the compound of the present invention is used as a plant growth regulator, it can be used by formulating it according to a usual pesticide formulation method. Since the compound of the present invention has plant elongation inhibitory activity and plant germination inhibitory activity over a long period of time, it can be expected to have an effect of prolonging the life of preservation of seeds, an effect of sustaining vegetative growth of plants and increasing yield, etc., It can be used for various purposes as an active ingredient of a plant growth regulator.

[0005]

EXAMPLES The present invention will be described in more detail with reference to production examples and reference test examples, but the present invention is not limited to these examples. Production example Starting material Methyl (2Z, 4E and 2E, 4E) -3-Methyl-5-
(2 ', 6'-Dimethyl-6'-(trifluoromethyl) -1'-cyclohexene-1'-yl) -2,4-pentadienoate (Compound 1) 215 mg (0.71 mmol) carbon tetrachloride N- in 15 ml of solution
200 mg (1.12 mmol) of bromosuccinimide and benzoyl
2 mg (0.008 mmol) of peroxide was added, and the mixture was heated under reflux for 6 hours. After cooling to room temperature and filtering, 0.6 ml of quinoline (0.005
mmol) was added and the mixture was concentrated and heated at 100 ° C. for 1 hour. After cooling to room temperature, the reaction solution was poured into 50 ml of a 1% aqueous solution of sulfuric acid and extracted 3 times with 50 ml of diethyl ether. The ether layer was washed with 5 ml of a saturated aqueous solution of sodium hydrogen carbonate and 5.0 ml of water, dried over anhydrous sodium sulfate and then concentrated to give 115 mg of a brown oily substance.
Got This was subjected to silica gel column chromatography (3.5: 1 with hexane-ethyl acetate (19: 1) as an eluent.
g, 0.4cm inner diameter x 17cm), dehydro form (compound 2)
75 mg of a mixture of the unreacted starting material (compound 1) was obtained.
Rose Bengal is added to 5 ml of a 75 mg solution of this mixture in methanol.
20 mg (0.02 mmol) was added, and the mixture was stirred at 30 ° C for 13 hours while irradiating with a fluorescent lamp in an oxygen atmosphere. The reaction solution was concentrated, dissolved in a small amount of methanol and adsorbed on 1 g of basic alumina, the methanol was distilled off, the residue was suspended in 5 ml of hexane and stirred at room temperature for 2 hours. This is an alumina column (7g, 0.8cm inner diameter x
Silica gel column chromatography (1.5 g, 0.35 cm) using 54 mg of the crude product obtained by elution with ethyl acetate as the eluent with hexane-ethyl acetate (4: 1-10: 3).
Inner diameter x 10.5 cm), isomer mixture (Compound 3) 20 mg
Got This was dissolved in 0.3 ml of methanol, 1 ml of a 1N aqueous sodium hydroxide solution was added, and the mixture was stirred at room temperature for 2 hours.
The reaction mixture was diluted with 10 ml of water, acidified (pH 2) with 1N hydrochloric acid, and extracted 4 times with 10 ml of ethyl acetate. The ethyl acetate layer was washed with 1 ml of water, dried over anhydrous sodium sulfate, and concentrated to obtain 12.3 mg of a yellow oily substance. This was subjected to HPLC (column, YMC AQ323) using 50% methanol / 1% acetic acid as an eluent.
(10x250mm); flow rate, 3.5ml / min; detection, UV254nm)

[Chemical 4] (±) -8 ', 8', 8'-trifluoro body (hereinafter,
The compound a of the present invention is referred to as "a". ) 0.5 mg (yield 0.22%) and

[Chemical 5] (±) -9 ', 9', 9'-trifluoro form (hereinafter,
It is referred to as the present compound b. ) Was obtained (2.1 mg, yield 0.93%).
The spectrum data is shown below. Compound of the present invention a ¹ H-NMR (400 MHz, CD ₃ OD, TMS): δ (ppm) 1.26 (3 H, s,
H-9 '), 1.95 (6H, d, J = 1.2Hz, H-6 and H-7'), 2.67
(1H, d, J = 19.6Hz, H-5'-proR), 2.72 (1H, d, J = 19.6H
z, H-5'-proS), 5.85 (1H, br s, H-2), 5.92 (1H, s,
H-3 '), 5.98 (1H, d, J = 15.9Hz, H-5), 7.69 (1H, d, J = 1
5.9Hz, H-4) UV λmax (MeOH) nm (log ε): 242.5 (4.36) High resolution MS of methyl ester: Calculated value for C ₁₆ H ₁₉ O ₄ F ₃ 332.1236; found value 332.1221. Compound of the present invention b ¹ H-NMR (400MHz, CD ₃ OD, TMS): δ (ppm) 1.33 (3H, s,
H-8 '), 1.90 (3H, s, H-7'), 1.94 (3H, d, J = 1.2Hz, H
-6), 2.38 (1H, dd, J = 16.8 and 0.9Hz, H-5'-proR),
2.91 (1H, d, J = 16.8Hz, H-5'-proS), 5.86 (1H, br s,
H-2), 5.94 (1H, s, H-3 '), 6.02 (1H, dq, J = 16.2Hz, J
_HF = 2.8Hz, H-5), 7.58 (1H, d, J = 16.2Hz, H-4) UV λmax (MeOH) nm (logε): 239.5 (4.39) High resolution MS of methyl ester: C ₁₆ H ₁₉ Calculated for O ₄ F ₃ 332.1236; found 332.1208.

Next, a test example will be shown. Formula 6

[Chemical 6] (±) -abscisic acid represented by is used as a comparative compound.

Reference Test Example 1 (Lettuce Seed Germination Inhibition Test) A filter paper was laid on a petri dish having an inner diameter of 6 cm, and a methanol solution of each sample was added thereto, and then methanol was removed under reduced pressure. Add 3 ml of deionized water and lettuce ( Lactuca
50 seeds of sativa L. cv. Grand Rapids) were sown and the germination number was measured after culturing for 2 days, 3 days, 4 days and 5 days under continuous light at 25 ° C. The inhibition rate was calculated according to the following formula 1 and the IC ₅₀ (μM) value was determined from the calculated inhibition rate.
In addition, it was used as a control that was cultured only with deionized water.

[Equation 1] Germination inhibition rate (%) = {(germination number of control
50-germination number of each sample) / (germination number of control 50)}
× 100 The results are shown in Table 1.

[Table 1]

Reference Test Example 2 (Second Rice Leaf Sheath Elongation Inhibition Test) Rice ( Oryza sativa L. cv. Nihonbare) seeds were immersed in ethanol for 5 minutes and subsequently in 1% antiformin for 1 hour, and then in running water for 3 minutes. Washed for hours. Soak the seeds in water for 30
It was cultivated at ℃ for 2 days and germinated. Sample solution in methanol
After putting in a 100 ml glass tube to remove methanol, 2 ml of deionized water was added. Seven seeds of germinated seeds were put in each well and sealed with a polyethylene film. 30 ° C under continuous light
The second leaf sheath length was measured after culturing for 7 days and the inhibition rate was calculated according to the following equation 2. In addition, what was cultured only with deionized water served as a control.

[Equation 2] elongation inhibition rate (%) = {(second leaf sheath length of control 26.4 mm-second leaf sheath length of each sample) / (second leaf sheath length of control 26.4 mm)} × 100 The results are shown in Table 2. Show.

[Table 2]

[0009]

The compound of the present invention has an excellent plant growth regulating action.

Claims (1)

[Claims] 1. Formula 1 An abscisic acid derivative represented by.