148613-80-3Relevant academic research and scientific papers
General syntheses of 1-alkyltoxoflavin and 8-alkylfervenulin derivatives of biological significance by the regioselective alkylation of reumycin derivatives and the rates of transalkylation from 1-alkyltoxoflavins into nucleophiles
Nagamatsu, Tomohisa,Yamasaki, Hirofumi
, p. 130 - 137 (2007/10/03)
Regioselective alkylations of reumycin derivatives under alkaline conditions with a dialkyl sulfate or alkyl halide in 1,4-dioxane or DMF to provide 1-alkyltoxoflavin or 8-alkylfervenulin derivatives of biological significance, are described. Namely, the primary and secondary alkylations of reumycin derivatives with appropriate dialkyl sulfates or alkyl bromides under alkaline conditions in 1,4-dioxane gave predominantly 1-alkyltoxoflavin derivatives, while the same alkylations in DMF instead of 1,4-dioxane gave predominantly 8-alkylfervenulin derivatives. In the case of tertiary alkylation, the reumycin derivative with 2-bromo-2-methylpropane in both solvents under the same conditions yielded only the 1-alkyltoxoflavin derivative. Moreover, the rates of transalkylation from 1-alkyltoxoflavin derivatives into nucleophiles, e.g. DMF and n-butylamine, are also described. That is, the toxoflavin derivatives possessing a primary alkyl group at the 1-position were easily dealkylated from the 1-position by heating with DMF, whereupon reumycin (i.e., 1-dealkyltoxoflavin, 8-dealkylfervenulin) derivatives were formed. In other words, transalkylation from the toxoflavin derivatives into DMF took place, However, the transalkylation of 1-alkyltoxoflavin derivatives possessing a secondary or tertiary alkyl group at the 1-position was not observed under such conditions. On the other hand, when heating 1-alkyltoxoflavin derivatives with n-butylamine in 1,4-dioxane, the transalkylations were more easily observed even in the case of 1-alkyltoxoflavin derivatives substituted by a tertiary alkyl group.
Facile and general syntheses of 1-alkyltoxoflavin and 8-alkylfervenulin derivatives of biological significance by the regiospecific alkylation of reumycin (1-demethyltoxoflavin, 8-demethylfervenulin) derivatives
Nagamatsu, Tomohisa,Yamasaki, Hirofumi
, p. 643 - 650 (2007/10/03)
Regiospecific alkylation of reumycins (6) under alkaline conditions with a dialkyl sulfate or alkyl halide in dioxane and in DMF to provide 1-alkyltoxoflavins (5) of biological significance and 8-alkylfervenulins (7), respectively, is described.
Syntheses of 3-substituted 1-methyl-6-phenylpyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones (6-phenyl analogs of toxoflavin) and their 4-oxides, and evaluation of antimicrobial activity of toxoflavins and their analogs
Nagamatsu,Yamasaki,Hirota,Yamato,Kido,Shibata,Yoneda
, p. 362 - 368 (2007/10/02)
6-Phenyl analogs of toxoflavin {1-methyl-6-phenylpyrimido[5,4-e]-1,2,4-triazine-5,7(1H,6H)-diones} (7a-f) and their 4-oxides (8a-f) were synthesized by nitrosative or nitrative cyclization of the aldehyde hydrazones (6a-f) of 6-(1-methylhydrazino)-3-phenyluracil (5). Both sets of compounds, 7a-f and 8a-f, gave the corresponding 1-demethyl derivatives (10a-f) upon treatment with nucleophiles such as dimethylformamide (DMF) and acetic acid under heating. The activities of toxoflavins (1a-e), toxoflavin 4-oxides (3a-e) and their 6-phenyl analogs (7a-f and 8a-f) against a variety of bacterial and fungal strains were examined. Most of the compounds showed strong inhibitory activities against gram-positive bacteria. Among the compounds, 1c, 1d, 1e, and 3c exhibited the strongest inhibitions of Micrococcus lutea (0.5 μg/ml minimal growth-inhibitory concentration) and Staphylococcus aureus 4R (1 μg/ml), as well as Bacillus subtilis and Staphylococcus aureus (1-2 μg/ml). Most of the compounds had strong antifungal activity (2-100 μg/ml minimal growth-inhibitory concentration) against Candida albicans and Saccharomyces cerevisiae.
