76782-21-3

Upstream product

• 76782-20-2 ethyl 6-benzoyl-5-oxo-2,7-dioxabicyclo-[4.1.0]hept-3-ene-3-carboxylate 
• 129118-10-1 2-[(dimethylamino)methylene]-1-phenyl-1,3-butanedione 
• 93-91-4 1-phenylbutan-1,3-dione 
• 78999-94-7 (E)-5-Benzoyl-6-dimethylamino-2,4-dioxo-hex-5-enoic acid ethyl ester 
• 76782-19-9 ethyl 5-benzoyl-4-oxo-4H-pyrane-2-carboxylate 

Relevant academic research and scientific papers

6-Substituted pyranone compounds and their use as pharmaceuticals

Compounds are described of the formula STR1 in which R1 is COOR5, CONHR5, cyano, 5-tetrazolyl or R6, where R5 is hydrogen or C1-8 alkyl and R6 is phenyl or naphthyl, the phenyl or naphthyl group being optionally substituted by one or more group selected from halogen, C1-6 alkyl, C1-4 alkoxy, hydroxy, benzyloxy, nitro, trifluoromethyl, carboxyl, C1-4 alkylsulphinyl, C1-4 alkylsulphonyl, N(R5)2, NHCOR5 and SR5 ; R2 is R6 or --CH=CH--R6 when R1 is COOR5, CONHR5, cyano or 5-tetrazolyl, or R2 is --CH=CH--R6 when R1 is R6 ; R3 is hydrogen, C1-6 alkyl, halogen, hydroxy or --OCH2 R6 ; and R4 is hydrogen, C1-6 alkyl or halogen; and salts thereof. The compounds have pharmaceutical properties and in particular are useful in the treatment of immediate hypersensitivity conditions such as asthma.

THE SYNTHESIS AND REARRANGEMENT OF EPOXYPYRONES

The oxidation of 5-acyl-4-oxo-pyran-2-carboxylic acid esters 1,2 to novel epoxypyrones and subsequent rearrangement to the previously inaccesible 6-substituted-5-hydroxy or 5-chloropyrones 6 - 9 are described.