CS275955B6 - 3-n-hexyl-6-nitro-2-benzothiazolinone - Google Patents

Abstract

Salt prepared previously unknown 3-n-hexyl-. -6-nitro-2-benzothiazolinone of the above formula. The synthesis of the above compound is carried out by reacting the potassium salt of 6-nitro-2-benzothiazolinone with n-hexyl iodide in a mixture of ethanol and water at boiling. The compound is effective as a stimulator of the growth of roots and stems of corn and is also effective as a regulator of the growth and synthesis of chlorophyll of green algae.

Description

CS 2’7595'5 0 6

The invention relates to 3-n-hexyl-6-nitro-2-benzothiazolinone.

3-Substituted derivatives of 6-nitro-2-benzothiazolinone have shown activity as plant growth regulators (DAmico ).. US Pat. 4,282,029 /1981/, Sidóová, E., Blanáriková, V., Mitterhauszerová, L. and Králová, K. CS 270,539) and as herbicides (0 Amico J.J. US Pat. 4,185,990 /1980/).

We have now discovered that a previously unknown compound with the formula stimulates root and stem growth in corn and simultaneously regulates the growth and chlorophyll synthesis in green algae in a concentration-dependent manner.

At the same time, a method of preparing the above compound was discovered by reacting the potassium salt of 6-nitro-2-benzothiazolinone with n-hexyl iodide in a mixture of ethanol and water at boiling temperature.

The following examples illustrate, but are not intended to limit, the preparation and properties of the compounds of the invention.

Example 1.

Preparation of 3-n-hexyl-6-nitro-2-benzothiazolinone'

6-Nitro-2-benzothiazolinone (5.9 g, 0.03 mol) was dissolved under boiling in a solution of potassium hydroxide (2.0 g, 0.03 mol) in a mixture of water (10 cm ³ ) and ethanol (20 cm ³ ). To the solution was added n-hexyl iodide (6.35 g, 0.035 mol), the reaction mixture was refluxed for 3 hours and then left overnight at 5 °C. The product with a mp of 61-66 °C was precipitated from the solution in an amount of 7.6 g (90.5%). '

The sample for analysis was recrystallized from a 4:1 mixture of ethanol and water using activated charcoal to give pure 3-n-hexyl-6-nitro-2-benzothiazolinone with a melting point of 68-70 °C.

M.h. = 280.35

For .

calculated %: C 55.70 H 5.75 N 9.99 S 11.44 found %: 55.77 5.76 10.01 11.46

Example 2

Test of phytotoxicity and stimulatory) effectiveness of the compound according to the invention

Table for example 2

Effect of the compound according to the invention on the prolonged growth of roots and stems of maize (Zea mays L.) after 72 hours of incubation in the dark, expressed as a percentage of the control sample

CS 275955 B 6

Concentration and mol.dm ^- } % control sample root length /- ^3, 0.05 stem length 1.10 ^-4 ?1> 1 - 1.3 05.1 and 3.1 1.10 ^-5 107.2 and 1.5 120.8 6.6 1.10 ^-6 112.2 í 2.5 ' 116.2 4.2 1.10 ^-7 113.2 - 2.2 126.9 3.2 1.10" ⁸ 120.6 and 2.9 120.5 and 3.7 1.10 ^-9 114.0 - 2.6 122.2 and 1.7 1. II) ^-10 116.7 4.1 115.0 and 4.3

The phytotoxicity of the compound of the invention was evaluated by measuring the elongation growth of the root and stem of corn (Zea mays L.) (Murín, A., Koleková, A., Váchová, M. and Bagula, š., Biology /Bratislava/ ^5,, 937 /1980/, Sekerka, V. and Sutoris, V., Pofnohospodárstvo 31, 832 /1985/). .

Corn seeds were swollen in aqueous solutions of the compounds according to the invention at a concentration of 1.10 ^-4 to 1.10 ^-70 mol.dm} for 24 hours, then placed on filter paper moistened with the respective solutions of the tested concentrations and pre-germinated in the dark for 72 hours at room temperature, while the rolled-up cylinders of filter paper were placed in perforated polyethylene bags (ČSN 46 0610). After this time, the length of the shoot and the above-ground part of the plant was measured. The results were evaluated as a percentage of the control sample. Due to the low solubility of the compound according to the invention in water, the tested concentrations were prepared by diluting with water its solution in N,ίΙ-dimethylformamide at a concentration of -? -3 to 1.10 mol.dm . Individual control samples for the tested concentrations of the compound according to the invention contained the corresponding amount of pure solvent.

At low concentrations of the compound according to the invention, in the concentration range of 1.10 ³ to 1.10 3 mul.dm ^- }, the compound according to the invention had a stimulating effect on the growth of corn roots and stems.

Example 3

Regulatory activity of the compound according to the invention on the growth and chlorophyll synthesis of green algae

Table for example 3

The regulatory effectiveness of the compound according to the invention on the growth and synthesis of chlorophyll of the algae Chlorella vulgari s

Concentrations and mol.dm *í Controls - Chlorophyll Absorbance 1.10 ^-4 77.9 0.8 71.3 - 1.1 1.10 ^-5 77.1 - 8.8 84.5 2.0 1.10 ^-6 96.6 14.7 100.2 - 10.0 1.10 ^-7 109.7 and 15.2 101.9 - 9.0 .9 1.10 ⁷ 106.2 10.3 98.0 - 1.2

CS 275955 8 6

Chlorella vulgaris algae were grown by stepwise cultivation at a temperature of 25 - 1 °C with a light regime of 16 hours light, 8 hours dark in a culture medium according to Šetlík (Šetlík I.: Annual Report of Algolog. Lab. for 1967, 71-140, Třeboň, 1968). The test substance was added to the culture medium in a solution of N,M-dimethylformamide (total solvent content in the culture medium - 1%) and the same solvent content was added to the control samples. The culture flasks were inoculated with an exact volume of a homogeneous algae suspension. After 7 days of cultivation, the volume of the culture medium was made up to the original volume with distilled water (to compensate for water evaporation) and in the suspension! The absorbance at 660 nm (proportional to the number of algal cells) and the chlorophyll content after its extraction) with N,N-dimethylformamide from centrifuged algal cells were measured (Inskeep, W.P., Bloom, P.R.: Plant Physiol. 77 /2/i 483-5, 1958). The obtained values of these parameters were compared with the values of the parameters of the simultaneously cultured control samples and evaluated as a percentage of the value.

The compound according to the invention inhibits algae growth and chlorophyll synthesis of green algae at concentrations of 1.10 mol.dm to 1.10 mol.dm.

It is significant that the compound according to the invention has a new, previously unknown structure and has a regulatory effect on the growth and synthesis of chlorophyll in the algae Chlorella vulgaris.

Particularly significant is the fact that the compound according to the invention at a concentration of 1.10 ¹ 1.10 ^-1 θ mol.dm ¹ stimulates the growth of roots and stems in corn.

The compound according to the invention can be used as an active ingredient in preparations for stimulating plant growth and regulating green algae, alone or in a mixture with other substances, and also as an intermediate for further syntheses.

Claims (2)

3 CS 275955 B 6 Algae Chlorella vulgaris were grown by cultivation at 25 - 1 ° C with a light regime of 16 hours, 8 hours darkness in a culture medium according to Šetlík (Šetlík I: Annual Report of Algolog. Lab. For 1967, 71-140, Trebon, 1968). The test substance was added to the culture medium in a solution of N, N-dimethylformamide (total solvent content in the culture medium - 1%) and the same solvent content was added to the control samples. Cultivation flasks were inoculated with an exact volume of homogeneous algae suspension. After 7 days of culture, the volume of culture medium was replenished with distilled water to the original volume (equilibrium of water evaporation) and the absorbance at 660 nm (proportional to the amount of algal cells) and chlorophyll content were measured in the cell suspension. its extraction) N, N-dimethylformamide from the centrifuged algal cells (Inskeep, WP, Bloom. PRi Plant Physiol. 77/2 / 483-5, 1958). The obtained values of these parameters were compared with the values of the parameters of the currently cultured control samples and evaluated by the percentage value. The compound of the invention inhibits algal growth and chlorophyll synthesis of green algae at -7-3-9-3 concentrations of 1.10 mol.dm to 1.10 mol.dm Significantly, the compound of the invention is a new, hitherto unknown structure and has a regulating effect on growth and synthesis chlorophyll algae Chlorella vulgaris. Of particular interest is the fact that the compound of the present invention stimulates the growth of roots and stems in maize, and the compound of the invention can be used as an active ingredient of plant stimulation and green algae control agents. this alone or in admixture with other substances, further as an intermediate for further syntheses 1. P-N-Hexyl-6-nitro-2-benzothiazolinone of Formula 0. 2 CH 3 2. Process for preparing the compound according to claim 1, characterized in that the potassium salt of 6-nitro-2-benzothiazolinone is reacted with n-hexyl iodo in a mixture of ethanol and water at boiling point.