1,2-Dimethylhydrazine hydrochlorides

A group of 28 male Fischer rats, seven weeks of age, was treated by gavage with a single dose of 35 mg/kg bw 1,2-dimethylhydrazine hydrochloride dissolved in 0.1 M sodium acetate buffer. The animals were killed 1.5 years after treatment and 22/28 (78.6%) treated rats had colon epithelial tumours [detailed histological description not given]. One of the rats with colon tumours also developed a small intestinal tumour and another had a tumour of the Zymbal gland (Schiller et al., 1980). 

In another study, 3-aminobenzamide (an inhibitor of poly(ADP-ribose)polymerase) enhanced the induction of y-GT-positive foci produced in the liver by 1,2-dimethylhydrazine in Wistar rats but not in Fischer rats. Rats were administered a single intraperitoneal injection of 100 mg/kg bw 1,2-dimethylhydrazine hydrochloride dissolved in 0.4 mM EDTA followed 4 h later by an intraperitoneal injection of either 600 mg/kg bw 3-aminobenzamide in dimethylsulfoxide or dimethylsulfoxide alone. Two weeks later, the rats were placed on a diet containing 0.02% 2-AAF for two weeks in the middle of this period, a single intragastric dose of carbon tetrachloride was administered. The rats were killed five weeks after 1,2-dimethylhydrazine administration. The number of y-GT positive foci per cm 2, their size and the area occupied by foci were significantly higher in Wistar rats treated with 1,2-dimethylhydrazine and 3-aminobenzamide than in those given only 1,2-dimethylhydrazine and dimethylsulfoxide. This effect was not seen in similarly treated Fischer rats (see Table 12) (Denda et al., 1988). 

Pyran 85b readily gave with various primary amines RNH2 at room temperature ring-opened products formulated as 506.62 If hydrazine hydrochloride or A,A -dimethylhydrazine and perchloric acid were used instead of the amines, the ring opening was accompanied by a secondary ring closure to lead to bispyrazolyl derivatives 507 or 508, respectively.418... 

Dimethyl-3,3-di-/i-butyallene, 14 Dimethylformamide, 198 Dimethylformamide dimethyl acetal, 198-200 Dimethylglyoxime, 395 2,6-Dimethyl-A5-heptenal, 10 N,N-Dimethylhydrazine, 200-201, 491 N, 0-DimethyIhydroxylamine hydrochloride, 201... 

Note 7) the residual liquor is evaporated to dryness under reduced pressure on a water bath. The crystalline dihydrochloride is treated with 25 cc. of absolute ethyl alcohol, and the mixture is evaporated to dryness imder reduced pressure. This treatment is repeated, and the dihydrochloride is crushed with a mixture of 25 cc. of absolute alcohol and 2-3 cc. of tloncentrated hydrochloric acid, filtered and washed with 10-15 cc. of cold absolute alcohol. The first fraction of dimethylhydrazine dihydrochloride, after being dried in a vacuum desiccator, weighs 22-23 g- evaporation of the mother liquors and further treatment with 5-6 cc. of absolute alcohol and a little hydrochloric acid, a second fraction of 3 g. of the hydrochloride is obtained. Repetition of this procedure yields a third fraction amounting to about 0.5 g. (Note 8). The total yield is 25-26 g. (75-78 per cent of the theoretical amount). 

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