49748-48-3Relevant articles and documents
Endothelin receptor antagonists
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, (2008/06/13)
The present invention provides novel compounds represented by the general formula I: STR1 wherein R 1 is a straight or branched lower alkyl, a cycloalkyl-lower alkyl, an aryl-lower alkyl, a cycloalkyl, an aryl an aryl-cycloalkyl, lower alkoxy, an aryloxy, or a heteroaryl;R 2 is hydrogen, a straight or branched lower alkyl, a cycloalkyl, or a cycloalkyl-lower alkyl;R 3 and R 3 '' are each the same or different and each is hydrogen atom, a straight or branched lower alkyl, a cycloalkyl, an aryl-lower alkyl, an aryl, or a heteroaryl; orR 3 and R 3 '' together form a ring structure;R 3 "" is hydrogen, lower alkyl or an aryl; orR 2 and R 3 "" together form a lower alkylene group --(CH 2) n -- wherein n is an integer of 1, 2 or 3; orR 2 and R 3 "" together form a group represented by the formula: --(CH 2) p --Ar-- or --Ar--(CH 2) p --, respectively, wherein p is zero or an integer of 1 or 2, and Ar is an arylene or heteroarylene;C( X) is C( O), C( S), C( NH), C( N-lower alkyl); C NH--OH, or CH 2 ;Y is a direct bond, --NH--, a lower alkyl-N, an oxygen atom, or methylene; orC( X) is CHOH and Y is a direct bond or methylene;R 4 is --(CH 2) s --Ar'' wherein s is zero or an integer of 1, 2 or 3; and Ar'' is an aryl, or a heteroaryl; andR 5 is carboxy, substituted or unsubstituted carboxamide, PO(OH) 2, tetrazole, CH 2 OH, CN, or hydrogen;and salts thereof.
SYNTHESIS OF 3-ARYL-4,5-DIHYDRO-5-HYDROXY-1,2-OXAZOLES BY REACTION OF SUBSTITUTED BENZONITRILE OXIDES WITH THE ENOLATE ION OF ACETALDEHYDE.
Di Nunno, L.,Scilimati, A.
, p. 2181 - 2190 (2007/10/02)
By reaction of substituted benzonitrile oxides with the enolate ion of acetaldehyde (quantitatively generated by the known cycloreversion of THF in the presence of n-butyllithium) a number of 3-aryl-4,5-dihydro-5-hydroxy-1,2-oxazoles (previously unknown or, in two cases, only synthesized by different procedures) have been isolated in high yields.Treatment of such hydroxy-isoxalines with some common bases allows their conversion in high yields into the corresponding isoxazoles.
SITE SELECTIVITY IN THE REACTIONS OF 1,3-DIPOLES WITH NORBORNADIENE DERIVATIVES
Cristina, D.,Amici, M. De,Micheli, C. De,Gandolfi, R.
, p. 1349 - 1357 (2007/10/02)
The cycloadditions of arylazides, benzonitrile oxides and diphenylnitrile imine to norbornadiene derivatives 1a-c showed varying degree of site- and stereo-selectivity.With dipolarophile 1a arylazides and benzonitrile oxides attack, preferentially, the electron-poor tetrasubstituted double bond, while in the case of 1b and 1c is the substituted double bond which enters the cycloaddition.By contrast, 2-diazopropane and C-phenyl-N-methylnitrone react with the sole tetrasubstituted double bond of 1a-c in stereo- and site-specific cycloadditions.The quantitative evaluation of the two possible reaction paths was performed by glc analysis.The compounds detected were those arising from Diels-Alder cycloreversions of the thermally labile intermediate adducts 2 and 3 (Scheme 1).The results were rationalized on the basis of a qualitative perturbation treatment which considers frontier orbital interactions only.
