Indoxyl derivatives

Reaction of enaminones and carboxylic acids is mainly interesting as a route for cyclization of suitable substituted enaminoketones to N-heterocycles45. In this way iV-cyclohexenylglycines can cyclize to indoxyl derivatives (equation 30). By a similar intramolecular acylation at the / -carbon of enaminones, fused indoles or pyrrole derivatives are obtained46-48. 

Hunteracine, a remarkably stable alkaloid of Hunteria ebumea, which survives the usual methods for degrading quaternary salts and can be sublimed as its chloride or bromide salt, has the constitution (141). An indoxyl derivative obtained by... 

Dienophile. This polycarbonyl compound forms Diels-Alder adducts, which are versatile intermediates for various syntheses. For example, an indoxyl derivative is accessible on reaction of its butadiene adduct with a primary amine and dehydrogenation. 

Maier, W., B. Schumann, and D. Groger, Biosynthesis of indoxyl derivatives in Isatis tinctoria and Polygonum tinctorium. Phytochemistry, 29, 817-819 (1990). 

Indoxyl derivatives LC, detection limits using FIA Indoxyl sulfate 2.3 pmol, indoxyl phosphate 3.1 pmol, indoxyl acetate 1.7 pmol, indoxyl 1,3-diacetate 0.4 pmol, indoxyl ) -D-glucoside 0.0015 pmol, indoxyl ) -D-galactoside 0.0015 pmol, indoxyl ) -D-glucuronide 0.0023 pmol, tryptophan 0.25 pmol (201)... 

Graiya Y, Ramana CV (2013) Synthesis of pseudo-indoxyl derivatives via sequential Cu-catalyzed SNAr and Smalley cyclization. Chem Commun 49(57) 6376-6378... 

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