2,6-DIMETHYLPYRAZINE FOR SYNTHESIS | 8.14618.0005

No differences in growth, food intake, haematological or clinical chemical parameters, or organ weight or histological appearance were observed between groups of control animals and those treated with 2-ethyl-3-methylpyrazine (No. 768) or 2,3-diethylpyrazine (No. 771). Males and females maintained on diets providing approximately 12 mg/kg bw per day of 3-ethyl-2,6-dimethylpyrazine (No. 776) had statistically significantly decreased growth rates and efficiency of food use, but no differences in haematological or clinical chemical parameters, organ weights, histological appearance were found from the control group. The reductions in body weight in test animals were not accompanied by evidence of toxicity, and the authors concluded that the reduced body-weight gain was not of toxicological significance.

2,6-dimethyl pyrazine, 108-50-9 - The Good Scents …

(i) Alkyl-, alicyclic-, and alkylaryl-substituted pyrazine derivatives (Nos 761–783, 798, and 952)

2,6-dimethyl pyrazine 2,6-dimethylpyrazine : ..

Yamada, K., Shimizu, A. & Ohta, A. (1993) Effects of dimethylpyrazine isomers on reproductive and accessory reproductive organs in male rats. .,16, 203–206.

2,6-Dimethylpyrazine For Synthesis | VWR

Yamada, K., Takahashi, H. & Ohta, A. (1992) Effects of 2,5-dimethylpyrazine on reproductive and accessory reproductive organs in female rats. ., 75, 99–107.

Liu, S.-Y. & Sylvester, D.M. (1994) Antiplatelet structure–activity relationship of tetramethylpyrazine. ., 55, 1317–1326.

Recommendation for 2,5-dimethyl pyrazine …

5,6,7,8,-Tetrahydroquinoxaline (No. 952) was added to the diet of rats at a concentration calculated to result in an average daily intake of 19 mg/kg bw for males and females. Measurements of growth rate and food intake, haematological and clinical chemical parameters, liver and kidney weights, and gross and histopathological appearance revealed no significant difference between test and control animals (Oser, 1970).Groups of 10 male Charles River CD rats were housed five to a cage and given diets containing 5-methyl-6,7-dihydro-5-cyclopentapyrazine (No. 781) at a concentration of at 100, 1000, or 8200 mg/kg, equivalent to 5, 50, and 410 mg/kg bw per day, for 13 weeks. The animals had access to water and food. Appearance, behaviour, appetite, gross signs of toxic effects, and deaths were monitored daily and were similar among test and control animals. Weekly measure-ment of body weights and food consumption revealed a transient reduction in the food consumption of animals at the high dose during the first 3 weeks, which was attributed to poor palatability of the diet. The body-weight gain of animals at the high dose was lower than that of control animals, but the efficiency of food use was generally unaffected at any dose. Haematological examinations performed on 10 control rats and five rats from each test group immediately before termination at week 13 revealed normal values. At necropsy, the weights of the liver, kidneys, heart, lungs, testes, spleen, and thyroid and adrenal glands were recorded. Tissues from these organs and from the stomach, duodenum, ileum, caecum, and colon were subsequently preserved in formalin for histopathological examination. The absolute and relative weights of the kidney were increased in animals at the two higher doses, but these changes were not accompanied by any lesions, and no treatment-related lesions were found in other tissues. The NOEL was 50 mg/kg bw per day on the basis of significantly reduced body-weight gain at 410 mg/kg bw per day (Wheldon et al., 1967).: Groups of 16 male and 16 female Wistar rats were maintained on diets containing acetylpyrazine (No. 784), calculated to provide an average daily intake of 8.2 mg/kg bw. Control animals were given a basic diet. The study protocol was the same as that described above (Posternak et al., 1975). Measurements of growth rate, food intake, haematological and clinical chemical parameters, organ weights, and gross and histopathological appearance showed no differences between test and control animals (Posternak et al., 1975).

Part 261: Synthesis of four pyrazines produced by females of the Korean apricot wasp, Eurytoma maslovskii

Bio-glycerol utilization: Synthesis of 2,6 ..

2,3-Diethyl-5-methylpyrazine (p-9) and 2-ethyl-3,5-dimethylpyrazine (p-8), despite their low abundance, had the highest odor-active values among the 13 pyrazines quantified in all products due to their very low odor thresholds.

Burdock, G.A. & Ford, R.A. (1990) Acute oral toxicity (LD50) study in the rat with 2-(mercaptomethyl)pyrazine. ., 1, 4.

Recommendation for 2,5-dimethyl pyrazine ..

Some neoplastic lesions were observed in treated and control male mice, but there was no statistically significant, dose-related trend. The increased incidence of lymphoma in female mice (controls, 0/13 (0%); low dose, 2/25 (8%); high dose, 6/29 (21%)) was statistically significant in the Cochran-Armitage test, but not in the Fisher exact test. The former test is for dose-related trends, while the latter is a direct comparison of treated with matched control groups. The authors noted that the increased incidence of lymphoma might have been associated with the decreased survival rate of female controls. On the basis of the small group size and poor survival of the female control group, the association between lymphoma and administration of pyrazinamide in female mice was deemed equivocal. No other statistically significant dose-related incidence of neoplasms was observed in female mice. The authors concluded that pyrazinamide was not carcinogenic in male B6C3F1 mice under the conditions of the study but that the carcinogenicity of the substance in female B6C3F1 mice could not be fully evaluated (National Cancer Institute, 1977).

More than 60 years of synthesis experience and multi-purpose plants enable TCI to offer more than 27,000 products as well as custom synthesis.

2,5-Dimethylpyrazine for synthesis | VWR

Groups of 10 male Charles River CD rats were housed five to a cage and given diets containing 5-methyl-6,7-dihydro-5-cyclopentapyrazine (No. 781) at a concentration of at 100, 1000, or 8200 mg/kg, equivalent to 5, 50, and 410 mg/kg bw per day, for 13 weeks. The animals had access to water and food. Appearance, behaviour, appetite, gross signs of toxic effects, and deaths were monitored daily and were similar among test and control animals. Weekly measure-ment of body weights and food consumption revealed a transient reduction in the food consumption of animals at the high dose during the first 3 weeks, which was attributed to poor palatability of the diet. The body-weight gain of animals at the high dose was lower than that of control animals, but the efficiency of food use was generally unaffected at any dose. Haematological examinations performed on 10 control rats and five rats from each test group immediately before termination at week 13 revealed normal values. At necropsy, the weights of the liver, kidneys, heart, lungs, testes, spleen, and thyroid and adrenal glands were recorded. Tissues from these organs and from the stomach, duodenum, ileum, caecum, and colon were subsequently preserved in formalin for histopathological examination. The absolute and relative weights of the kidney were increased in animals at the two higher doses, but these changes were not accompanied by any lesions, and no treatment-related lesions were found in other tissues. The NOEL was 50 mg/kg bw per day on the basis of significantly reduced body-weight gain at 410 mg/kg bw per day (Wheldon et al., 1967).