IE44686B1

IE44686B1 - N-methoxycarbonyl-n1-sulfonylhydrazines

Info

Publication number: IE44686B1
Application number: IE1630/81A
Authority: IE
Original assignee: Pfizer
Priority date: 1976-06-15
Filing date: 1977-05-20
Publication date: 1982-02-24
Also published as: IE44685B1; IE44685L; IE44686L

Description

The invention relates to novel N-methoxycarbonvl-N^-sulfonylhydrazines for use in preparing 3-t2-quinoxalinylmethylene)carbazate 1 4 K ,N -dioxides with useful antibacterial properties and/or with growth promotant properties in animals.

According to our Patent Specification No. .(44534 ), a process for preparing a methyl 3-(2- quinoxalinylmethylenejcarbazate n\. 2-2^dioxide of the formula: . 0 CH=N-NH-COOCH, ---(I) wherein R is hydrogen, alkyl, hydroxyalkyl, alkanoyl, benzoyl or 12 1 2 10 -COSR R wherein R and R are each hydrogen, alkyl, hydroxyalkyl or aminoalkyl, any such alkyl, hydroxyalkyl or aminoalkyl group containing 1 to 6 carbon atoms and any such alkanoyl group containing 2 to 7 carbon atoms, comprises reacting a compound of the formula: (II) I5 wherein R is as defined above and X is chlorine or bromine, with a compound of the formula: r3-nh-kh-cooch3 (III) )4686 - 3 wherein R3 is an aliphatic or aromatic sulphonyl group, in a reaction-inert solvent, in the presence of anhydrous potassium carbonate. Some of the compounds of formula (III) are the subject of claims in British patent no. 1505120.

The present invention provides compounds of the formula where R3 is a trifluoromethane or 2,2,2-trifluoroethane sulphonyl group.

The trifluoromethane sulphonyl (CFjSop and 2,2,2-trifluoroethane sulphonyl (CF^CK^SO^) groups are commonly known as the trifyl and tresyl groups respectively. The preferred compound of formula (III) is that in which R is trifyl, i.e. N-methoxycarbonyl-Ν'-trifylhydrazine .

Compounds of formula (I) in which R is hydrogen or alkyl containing 1 to 6 carbon atoms are described and claimed in British 1 2 Patent Specification No. 1058047, while those in which R is -CONR R are described and claimed in British Patent Specification No. 1365441.

The compounds of formula (III) are prepared by the general procedure described in J. Org. Chem. 40, 3450 (1975) and DS Patent no. 3925270 (1975). For example, N-methoxycarbonyl-Ν'-trifylhydrazine is prepared by adding a solution of triflic anhydride in methylene chloride dropwise to a methylene chloride solution containing an equimolar amount of methyl carbazate and a slight molar excess of triethylamine at -78°C. The resulting mixture is allowed to warm to room temperature and stirred for about 16 hours. The mixture is concentrated under vacuum at room temperature and the residue is then extracted with several portions of ether. The ether - 4 extract is concentrated under vacuum at room temperature to a waxy solid that is u?ed directly in the subsequent reaction without further purification. Alternatively, the omission of triethylamine and the use of two molar equivalents of methyl carba2ate yields the crystalline product.

The following examples illustrate the preparation of compounds of formula (III) according to the invention.

EXAMPLE 1 N-Methoxycarbonyl-N' -trifylhydrazine (A) Triflic anhydride (35.4 mmoles) in methylene chloride (40 ml) was added dropwise to a solution of methyl carbazate (35.5 mmoles) and triethylamine (38.9 mmoles) in methylene chloride (200 ml) at -78°C. with stirring. The resulting mixture was allowed to warm to room temperature and stirred for 16 hours. The mixture was concentrated at room temperature under vacuum and the residue was extracted with three 100 ml portions of refluxing ether. The combined ether extract was concentrated under vacuum at room temperature to yield a waxy solid (5.26 g., ca. 67%). The nmr spectrum of the crude product was consistent with the expected product contaminated with the triethylamine salt of triflic acid. The crude material was used directly without further purification for subsequent reactions.

(B) Methyl carbazate (336 mmoles) was added over a 20 minute period with stirring to a solution of triflic anhydride (178 mmoles) in methylene chloride (2000 ml) under a nitrogen atmosphere at -78°C.

The resulting solution was allowed to warm to room temperature and 44688 - 5 and stirred for 20 hours. The resulting thick white suspension was concentrated under vacuum at room temperature to give a white solid. This material was triturated with diethyl ether 1450 ml) and collected to give the methyl carbazate salt of triflic acid. The diethyl ether filtrate was concentrated under vacuum at room temperature to give a white solid which was triturated with hexane, collected, washed with hexane and dried to give the product as a white crystalline solid (field, 84%) mp 107-109°C.

Analysis Calculated for CjfigO^FjS: C,l6.21; H.2.25; N,12.61% Found: C,16.24; H,2.20; N,12.68% EXAMPLE 2 N-Methoxycarbony1-N1-tresylhydrazlne The method of Example 1 may be repeated employing tresyl chloride in place of triflie anhydride.

Claims

1. A compound of the formula: R 3 -NH-NH-COOCH 3 ---(III) wherein R is a trifluoromethane or 2,2,2-trifluoroethane sulphonyl 5 group.

2. N-Methoxycarbonyl-N 1 -trifylhydrazine. »

3. N-Methoxycarbonyl-N'-tresylhydrazine.