167223-42-9Relevant articles and documents
A valsartan synthesis method of alkylation impurity (by machine translation)
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Paragraph 0022; 0023, (2018/10/19)
A valsartan synthesis method of alkylation impurities, is to L - valine that may exist in the impurity D - valine, alanine, leucine isoleucine amino acid as the raw material and the like, in thionyl chloride under the conditions of the esterification reaction with methanol, after the reaction by reducing pressure methanol, then with 2 - cyano - 4' - bromomethyl biphenyl in the reaction under alkaline conditions, after completion of the reaction, saturated salt water washing, adding hydrochloric acid to adjust the pH=1 - 2, the temperature of the crystallization, filtering to obtain the target product valsartan alkylation impurity. The present invention is to provide high-purity impurity, will its known impurity used for alkylation of valsartan in mass analysis, the position of the clear of impurities in the sample, the degree of impurity of the sample inspection, optimizes the analytical method, contribute to improving the quality of valsartan research, for the production of valsartan reducing impurity, improve the quality of the valsartan; at the same time, this invention has mild condition, the reaction yield is higher, convenient operation and the like. (by machine translation)
RELATIONSHIPS BETWEEN THE STRUCTURE AND THE PHYTOTOXICITY OF THE FUNGAL TOXIN TENUAZONIC ACID
Lebrun, M. H.,Nicolas, L.,Boutar, M.,Gaudemer, F.,Ranomenjanahary, S.,Gaudemer, A.
, p. 77 - 84 (2007/10/02)
Tenuazonic acid (3-acetyl 5-sec-butyl pyrrolidine-2,4-dione) is a metabolite produced by the fungal pathogen of rice Pyricularia oryzae.It inhibits growth of plants by interferring with protein synthesis at the ribosome level.We have synthesized analogues of tenuazonic acid with various substituents at C-3 and C-5.Substituents at C-5 other than sec-butyl or n-propyl, decrease the phytotoxicity of the analogues.But substitutions at C-3 abolish the toxicity.Thus, tenuazonic acid seems to have the optimal structure for phytotoxicity.Tenuazonic acid induces rice leaf defence reactions (browning) of reactive varieties which are resistant to P. oryzae.Some of the analogues synthesized have a low level of phytotoxicity and are able to induce this leaf browning of the reactive rice varieties.Thus different structural features are required for phytotoxicity and for leaf browning.Key Word Index - Tenuazonic acid; pyrrolidine-2,4-diones; rice; phytotoxicity; Pyricularia oryzae; structure-activity.