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Process of preparing n-(5-nitro-2-furfurylidene) -3-amino-5-methyl-2-thiooxazolidone and new chemical compounds employed in the practice of such process
Process of preparing n-(5-nitro-2-furfurylidene) -3-amino-5-methyl-2-thiooxazolidone and new chemical compounds employed in the practice of such process
2 - Salicylidene - 1 - (2 - hydroxy propyl) dithiocarbazic acid is prepared by treating 1-salicylidene - 2 - (2 - hydroxy propyl) hydrazine with carbon disulphide in the presence of a base, e.g. sodium or potassium hydroxide, at a temperature of 5 DEG C. to 15 DEG C., followed by acidification at a temperature of 2 DEG C. to 5 DEG C. with dilute acid such as hydrochloric acid. The product may subsequently be converted to 3-salicylideneamino -5-methyl-2-thiooxazolidone by heating with lead acetate in solution in dimethylformamide, separating the precipitated lead sulphide and acidifying for example with dilute sulphuric acid. By steam distillation with 5-nitro-2-furfuraldehyde the 3-salicylideneamino-5-methyl-2-thiooxazolidone is converted into the 3-(51-nitro-21-furfuryladene) amino-5-methyl-2-thiooxazolidone of Specification 843,602.ALSO:A control agent for the treatment of tomato blight comprises as its active constituent 2-salicylidene - 1 - (2 - hydroxypropyl) - dithio-carbazic acid (see Group IV (b)) used suitably as a spray containing 80 p.p.m. of the active compound.
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