3921-69-5

Upstream product

• 7691-03-4 3-(γ,γ-dimethylallyl)-4-hydroxy-8-methoxy-2-quinolone 
• 41303-26-8 4,8-dimethoxy-3-(3'-methylbut-2'-enyl)-2-quinolinone 
• 109573-21-9 4-hydroxy-8-methoxy-3-(3-methylbut-3-enyl)quinolin-2(1H)-one 
• 50-00-0 formaldehyd 
• 7224-68-2 4-hydroxy-8-methoxyquinolin-2(1H)-one 
• 541-47-9 3-Methylbutenoic acid 
• 16940-66-2 sodium tetrahydroborate 
• 120185-97-9 2-(chloromercurymethyl)-3,4-dihydro-7-methoxy-2-methyl-2H,5H-pyrano{3,2-c}quinolin-5-one 
• 78-79-5 isoprene 
• 35989-00-5 7-methoxy-2,2-dimethyl-2H,5H,6H-pyran[3,2-c]quinolin-5-one 

Relevant academic research and scientific papers

Synthesis of pyranoquinoline alkaloids via (4+2) cycloaddition reaction

An easy route to synthesize pyranoquinoline based alkaloids like flindersine, haplamine, N-methylflindersine and its derivatives were performed from the respective 4-hydroxyquinolin-2(1H)-one, dimethyl acrylic acid and para formaldehyde through generation of O-quinone methide intermediates and subjecting (4+2) cycloaddition. Further, dihydro intermediates were oxidized by DDQ.

Simple efficient synthesis of pyranoquinoline alkaloids: Flindersine, khaplofoline, haplamine and their analogues

An efficient two step synthesis of pyranoquinoline alkaloids is described. Direct treatment of isoprene with 4-hydroxyquinolin-2(1H)-one in the presence of polyphosphoric acid furnished dihydroflindersine in good yield, and which on dehydrogenation led to a new synthesis of flindersine. Khaplofoline, a linear pyranoquinoline alkaloid, was obtained as a minor product. The syntheses of derivatives are also documented.

GLYCOLONE, A QUINOLONE ALKALOID FROM GLYCOSMIS PENTAPHYLLA

Key Word Index - Glycosmis pentaphylla; Rutaceae; leaves; glycolone; 2-quinolone alkaloid. - Glycolone, a quinolone alkaloid has been isolated from the leaves of Glycosmis pentaphylla.The structure of the compound has been established as 4,8-dimethoxy-3-(3-methyl but-2-enyl)-2-quinolone from physical and chemical evidences.

A NEW APPROACH TO HEMITERPENOID TRICYCLIC QUINOLONES. SYNTHESIS OF N-METHYLFLINDERSINE, KHAPLOPHOLINE AND OTHER STRUCTURALLY SIMILAR ALKALOIDS

A new and general synthesis of tricyclic quinolone alkaloids is described which, by cyclization of 3-butenyl-4-hydroxyquinolones promoted by mercury(II) ion or by formic acid, affords pyranoquinolones and pyranoquinolones, respectively, with regio- and site-selectivity better than those obtained employing known methodologies. 3-Butenyl-4-hydroxyquinolones have been reacted with mercury(II) acetate to give, after work-up, the corresponding 2-(chloromercurymethyl)pyranoquinolones, which have been reductively demercurated with sodium borohydride and then dehydrogenated by treatment with DDQ.Alternatively, from the same starting compounds the "linear" isomers are obtained by formic acid-promoted cyclization.N-Methylflindersine, khaplofoline and other structurally similar alkaloids have been obtained.

SYNTHESIS OF THE QUINOLINE ALKALOIDS BUCHAPINE AND RAVESILONE

Buchapine (I) has been synthesized in one step by a Claisen rearrangement of 3-(γ,γ-dimethylallyl)-4-(γ,γ-dimethylallyloxy)-2-quinolone (III).The total synthesis of ravesilone (II) has been carried out from γ,γ-dimethylallylmalonic acid-2-methoxyanilide (V) in three steps.