NO152436B - HAARFARGEMIDDEL - Google Patents

Abstract

1. Hair dyes based on oxidation dyes, characterized by a content of chlororesorcinols corresponding to the following formula see diagramm : EP0039807,P4,F2 in which the substituents R**1 to R**4 represent chlorine atoms, hydrogen atoms or methyl groups, the following combinations a) R**1 =Cl, R**2 =H, R**3 =H and R**4 =H, b) R**1 =Cl, R**2 =H, R**3 =CH3 and R**4 =H, c) R**1 =Cl, R**2 =H, R**3 =CH3 and R**4 =CH3 , d) R**1 =H, R**2 =H, R**3 =CH3 and R**4 =Cl, e) R**1 =CH3 , R**2 =Cl, R**3 =H and R**4 =Cl. applying, as coupler components and the developer substances normally used in oxidation hair dyes.

Description

Process for the production of chemotherapeutically useful nitrofuran compounds.

The invention relates to a process for the production of new nitrofuran compounds of formula I

where R denotes an ethyl or n-propyl group, this method being characterized in that a compound of formula II

is treated with an alkylating agent of formula RX, where R has the above meaning and X denotes bromine or iodine.

The process products are very

effective agents against parasites and can be used as an active component in mixtures intended to affect micro-organisms. In small amounts, they are harmful to gram-positive and gram-negative organisms. In the form of powders, solutions, elixirs, suspensions, tablets or the like together with readily available and common

emollients or carriers, these compounds can be used for combating and eradicating bacterial infections.

The compounds also have systemic chemotherapeutic properties. After administration per os to mice, which are fatally infected with Staphylococcus aureus or Salmonella typhosa, the animals could be prevented from dying using doses of approximately 110-150 mg/kg. If they are introduced into the feed intended for chickens infected with Eimeria tenella, in a content of approx. 0.022% by weight, protection against the ravages of the disease is achieved.

The starting compounds of the above formula II can be prepared according to patent no. 108,909.

Example 1.

2-propyl-6-(5-nitro-2-furyl)-3-pyridazinone.

A mixture of 25.0 g (0.12 mol) of 6-(5-nitro-2-furyl)-3(2H)-pyridazinone and 6.5 g (0.12 mol) of sodium methylate in 400 ml of methanol is refluxed under stirring for approx. 3 hours. After adding 30 ml of n-propyl iodide (n-propyl bromide can be used instead of the iodide), the mixture is refluxed overnight. The solvent is removed in a vacuum on a steam bath and the residue is shaken with approx. 300 ml 5% sodium hydroxide solution. The cold mixture is filtered and the residue is washed carefully with cold water. By recrystallization of the residue from dilute, aqueous ethanol, using charcoal, the above-mentioned product is obtained as yellow needles, which melt at 103-105° C. in a yield of 9.7 g (32.5 per cent).

During recrystallization, the melting point is increased to 106.5-107.5° C.

Example 2.

2-ethyl-6-(5-nitro-2-furyl)-3-pyridazinone.

A mixture of 50.0 g (0.24 mol) of 6-(5-nitro-2-furyl)-3(2H)-pyridazinone and 13.0 g (0.24 mol) sodium methylate in 1 liter of methanol is refluxed while stirring for approx. 3 hours. After adding 50 ml of ethyl iodide, the mixture is refluxed overnight. The solvent is removed in a vacuum on a steam bath and the residue is shaken with approx. 500 ml cold, 5% sodium hydroxide solution. The cold mixture is filtered and the residue is washed carefully with cold water. On recrystallization of the residue from dilute aqueous methanol, the above-mentioned product is obtained as pale yellow crystals which melt at 148-150° C in a yield of 22.4 g (39.5 per cent).

After recrystallization, the melting point is 149-149.5° C.

Claims (1)

Process for the preparation of chemotherapeutically useful 6-(5-nitro-2-furyl)-3-(2H)pyridazinones of the general formula where R denotes ethyl or n-propyl, characterized in that a compound of the formula is treated with an alkylating agent with "ormel RX", where R has the above meaning and X denotes bromine or iodine.