Cyclization of ((4- or 5-substituted-2-benzimidazolyl)thio)acetic acids. Isolation and identification of two possible isomers of substituted thiazolo(3,2-a)benzimidazol-3(2H)-one.
作者:KENJIRO TANAKA、MICHIKO INO、YASUOKI MURAKAMI
DOI:10.1248/cpb.29.1876
日期:——
Cyclizations of [(5-substituted-2-benzimidazolyl) thio] acetic acid (2a-e) to the corresponding thiazolo [3, 2-a] benzimidazol-3 (2H)-one (5 and 6) were successfully carried out by heating 2a-e in Dowtherm A or Ac2O/pyridine, and gave the two possible isomers (5a-e and 6a-e) in a ratio of nearly 1 : 1 in all cases. Separation of 5 and 6 was successfully carried out, and their structures (namely, the direction of cyclization) were suggested on the basis of the NMR spectra. Dowtherm A was more effective than Ac2O/pyridine, particularly for the cyclization of [(5-nitro-2-benzimidazolyl) thio] acetic acid (2a), which had been reported not to be cyclized with other reagents. Similar cyclization of [(4-methyl-2-benzimidazolyl) thio] acetic acid (2f) preferentially gave 8-methylthiazolo [3, 2-a]-benzimidazol-3 (2H)-one (6f).
Synthesis and antitrichinellosis activity of some 2-substituted-[1,3]thiazolo[3,2-a]benzimidazol-3(2H)-ones
作者:Anelia Ts. Mavrova、Kamelya K. Anichina、Dimitar I. Vuchev、Jordan A. Tsenov、Magdalena S. Kondeva、Mitka K. Micheva
DOI:10.1016/j.bmc.2005.06.046
日期:2005.10
Some new thiazolo[3,2-a]benzimidazolone derivatives were synthesized using two methods. The structures of the synthesized compounds were proved by means of IR, (1)H NMR and mass spectral data. Ab initio computations were performed in order to determine the electronic structure and geometry of the investigated molecules and to compare it to the geometry of albendazole. Biologically, experiments in vitro
使用两种方法合成了一些新的噻唑并[3,2-a]苯并咪唑酮衍生物。借助IR,(1)H NMR和质谱数据证明了合成化合物的结构。为了确定所研究分子的电子结构和几何形状并将其与阿苯达唑的几何形状进行比较,进行了从头算。在生物学上,完成了体外和体内实验,以鉴定获得的噻唑基苯并咪唑啉酮对旋毛虫的功效。对于浓度为100mg / kg mw的化合物4a和4c,化合物4a-c在旋毛虫病的肠道阶段的有效性为100%,在肌肉阶段的有效性为88%和80%。
TANAKA, KENJIRO;INO, MICHIKO;MURAKAMI, YASUOKI, CHEM. AND PHARM. BULL., 1981, 29, N 7, 1876-1886
作者:TANAKA, KENJIRO、INO, MICHIKO、MURAKAMI, YASUOKI
DOI:——
日期:——
SINGH S. P.; PARMAR S. S.; PANDEY B. R., J. HETEROCYCL. CHEM. <JHTC-AD>, 1977, 14, NO 6, 1093-1095