A novel and efficient synthesis of 2,5-substituted 1,2,4-triazol-3-ones
摘要:
A novel procedure for preparing 1,2,4-triazol-3-ones is described. Various alkyl, aryl, and heterocyclic groups were introduced successfully at both the N2 and C5 positions. The triazolone ring was constructed through an intramolecular cyclization of a novel acyclic precursor, which in turn was synthesized by treating a mono protected hydrazine with an acyl isocyanate. Under conditions that remove the hydrazine protecting group, the intramolecular cyclization occurs rapidly, to deliver the 2,5-substituted 1,2,4-triazol-3-ones in excellent yields (79-99%) without column purification. (c) 2005 Elsevier Ltd. All rights reserved.
作者:J. L. Archibald、D. R. Beardsley、G. M. F. Bisset、P. Fairbrother、J. L. Jackson、A. Opalko、T. J. Ward
DOI:10.1021/jm00182a009
日期:1980.8
These compounds are related to the benzamidopiperidines exemplified by indoramin. Some of the ureidopiperidines are more potent antihypertensiveagents than their benzamidopiperidine counterparts. Two examples, 1-(2-thenoyl)-3-[1-[2-(3-indolyl)ethyl]piperid-4-yl]urea and 1-(2-thenoyl)-3-[1-[4-(4-fluorophenyl)-4-oxobutyl]piperid-4-yl]urea (19 and 58), emerged as the most potent antihypertensive agents
A simple one-pot preparation of 2-pyridones from acyl isocyanates utilizing trimethylsilylketene
作者:Kiyo Takaoka、Toyohiko Aoyama、Takayuki Shioiri
DOI:10.1016/0040-4039(96)00982-3
日期:1996.7
Trimethylsilylketene reacts with acyl isocyanates to give 4-trimethylsiloxy-1,3-oxazin-6-ones which smoothly undergo the Diels-Alder reaction with dimethyl acetylenedicarboxylate and methyl propiolate to furnish 2-pyridones.
Compounds of formula ##STR1## in which hal represents halogen; R represents hydrogen or lower alkyl having 1 to 6 carbon atoms; R.sup.2 represents a subsituted or unsubstituted monocyclic heterocyclic group; and X represents oxygen or sulphur; or a pharmaceutically acceptable acid addition or quaternary ammonium salt thereof, are disclosed which have hypotensive and/or antihypertensive activity.
1-(N-Acyl-carbamoyl)-2-cyanoaziridines of the formula ##STR1## wherein X is oxygen or sulphur, Z is hydrogen or an organic radical, and Y is a carbonyl, sulphonyl, sulphinyl, sulphenyl, phosphoryl or phosphonyl radical, and salts thereof, exhibit immune-stimulating and cancerostatic activities.