95616-37-8Relevant academic research and scientific papers
MESOIONIC COMPOUNDS WITH A BRIDGED NITROGEN ATOM. 17. THIAZOLOQUINAZOLINIUM 3-OXIDES
Fedotov, K. V.,Romanov, N. N.
, p. 343 - 347 (2007/10/02)
The cyclization of (4-quinazolinylthio)phenylacetic and acetic acids gives extremely reactive thiazoloquinazolinium 3-oxides, which, depending on the structure of the mesoionic ring, react with either electrophilic or nucleophilic reagents.
Annulation of the Quinazoline Ring Utilizing Mesoionic Ring Systems
Potts, Kevin T.,Bordeaux, Kirk G.,Kuehnling, William R.,Salsbury, Ronald L.
, p. 1666 - 1676 (2007/10/02)
anhydro-3-Hydroxythiazoloquinazolin-4-ium hydroxides, prepared from the corresponding thioglycolic acid with cyclodehydrating agents and also from 4(3H)-quinazolinethiones and α-bromophenylacetyl chloride, were hydrolyzed at the 5-position of the quinazoline ring with hot water.Alkynic and alkenic dipolarophiles cycloadded readily in hot benzene; the former gave pyridoquinazolines and the latter 1:1 cycloadducts which lost H2S to give the above ring system.These procedures provided convenient annulation of a pyridinone to the c side of quinazoline.With ethyl acrylate, in addition to the normal 1:1 cycloadduct, a rearranged pyrroloquinazoline was obtained depending on the reaction conditions; analogous products were obtained with dimethyl fumarate. anhydro-1-Hydroxythiazoloquinazolinium hydroxides, preferably generated in situ from the corresponding thioglycolic acid and dicyclohexylcarbodiimide (DCC), and alkynic dipolarophiles in refluxing benzene readily gave pyridoquinazolines.Alkenic dipolarophiles also gave 1:1 cycloadducts, which lost H2S to form pyridoquinazolines, resulting in annulation of a pyridinone ring to the a side of quinazoline.
