94392-54-8

Upstream product

• 1705-09-5 3-methyl-4-oxoquinazoline-2-thione 
• 82323-46-4 phenylglyoxylic acid chloride p-toluenesulfonylhydrazone 
• 95616-64-1 S-(3-methyl-4-oxoquinazolin-2-yl)-α-phenylthioglycolic acid 
• 19078-72-9 bromo(phenyl)acetyl chloride 
• 1705-09-5 2-mercapto-3-methyl-3,4-dihydroquinazolin-4-one 
• 4870-65-9 2-bromophenylacetic acid 

Downstream Products

• 95616-76-5 C₂₂H₂₀N₂O₄S 
• 95616-76-5 C₂₂H₂₀N₂O₄S 
• 95616-72-1 C₂₁H₁₄N₄O₂S 
• 95616-69-6 ethyl 1,6-dioxo-5-methyl-2-phenyl-5H,11H-pyrido<1,2-a>quinazoline-4-carboxylate 
• 95616-67-4 dimethyl 1,6-dioxo-5-methyl-2-phenyl-5H,11H-pyrido<1,2-a>quinazoline-3,4-dicarboxylate 

Relevant academic research and scientific papers

Annulation of the Quinazoline Ring Utilizing Mesoionic Ring Systems

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.

Carbenoid Intermediates in the Synthesis of Mesoionic Anhydro-4-hydroxythiazolium Hydroxides

α-(Tosylhydrazono)phenylacetyl chloride and N-monosubstituted thioamides in dry, non-protic solvents and in the presence of Et3N give representatives of the title mesoionic ring system in good to excellent yields; carbene or carbenoid type intermediates a

Synthesis of Some Fused-ring Derivatives from 4(3H)-Quinazolone

A few more well-defined mesoionic thiazoloquinazolones have been synthesized and their properties recorded.Attempts to build-up analogous fused-ring mesoionic systems via 2-chloro-3-phenyl-4-quinazolone have not been successful.Several new triazolo