20110-02-5

Upstream product

• 139542-31-7 6-(1'-hydroxy-2',6',6'-trimethyl-4'-oxocyclohex-2'-enyl)-4-methylpyran-2-one 
• 22682-15-1 6-chloro-4-methylpyran-2-one 
• 3385-34-0 ethyl isodehydroacetate 
• 924-59-4 diethyl 3-methylpent-2-enedioate 
• 21293-29-8 (2Z,4E)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2,4-pentadienoic acid 
• 139571-43-0 4-methyl-6-(2'-oxopropyl)pyran-2-one 
• 372-42-9 (E)-3-methylpent-2-enedioic acid 
• 372-42-9 3-methylpent-2-enedioic acid 
• 139542-30-6 4-methyl-6-(2',6',6'-trimethyl-4'-oxocyclohex-2'-enyl)pyran-2-one 

Downstream Products

• 20109-89-1 (2Z,4E)-methyl 5-(1',4'-dihydroxy-2',6',6'-trimethyl-2'-cyclohexen-1'-yl)-3-methylpenta-2,4-dienoate 
• 21293-29-8 (2Z,4E)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl)-3-methyl-2,4-pentadienoic acid 

Relevant academic research and scientific papers

Biosynthesis of Abscisic Acid by the Non-mevalonate Pathway in Plants, and by the Mevalonate Pathway in Fungi

The biosynthetic pathways to abscisic acid (ABA) were investigated by feeding [1-13C]-D-glucose to cuttings from young tulip tree shoots and to two ABA-producing phytopathogenic fungi. 13C-NMR spectra of the ABA samples isolated showed that the carbons at 1, 5, 6, 4′, 7′ and 9′ of ABA from the tulip tree were labeled with 13C, while the carbons at 2, 4, 6, 1′, 3′, 5′, 7′, 8′ and 9′ of ABA from the fungi were labeled with 13C.The former corresponds to C-1 and -5 of isopentenyl pyrophosphate, and the latter to C-2, -4 and -5 of isopentenyl pyrophosphate. This finding reveals that ABA was biosynthesized by the non-mevalonate pathway in the plant, and by the mevalonate pathway in the fungi. 13C-Labeled ss;-carotene from the tulip tree showed that the positions of the labeled carbons were the same as those of ABA, being consistent with the biosynthesis of ABA via carotenoids. Lipiferolide of the tulip tree was also biosynthesized by the non-mevalonate pathway.

Preparation and analysis of some acetosugar esters of abscisic acid and derivatives

Racemic abscisic acid (ABA), the cis and trans 1′, 4′-diols (ABA diols) derived from ABA by reduction of the 4′ ketone, and the corresponding 4′-O-acetates were converted into various acetosugar esters by reaction of their cesium salts with the 1-chloroacetosugars derived from glucose, galactose, lactose, and maltose. Analytical separations of the acetosugar esters using high-performance liquid chromatography (LC) on reverse-phase columns were developed. Continuous flow secondary ion mass spectra (CFSIMS) of the various acetosugar esters were obtained and an LC/CFSIMS protocol employing multiple reaction monitoring was used to detect ABA acetoglucose ester in an acetylated extract obtained from plant cells that had been treated with ABA.

A Stereospecific Synthesis of (+/-)-Abscisic Acid

A convenient separation of (E)- and (Z)-3-methylpent-2-enedioic acids was devised, and it was shown that with acetyl chloride or thionyl chloride the (Z)-acid yields the cyclic anhydride while the (E)-acid forms 6-chloro-4-methylpyran-2-one.The chloropyranone by conventional chemistry gave 4-methyl-6-(2'-oxopropyl)pyran-2-one which condensed with 4-methylpent-3-en-2-one in the presence of pyrrolidine, yielding 4-methyl-6-(2',6',6'-trimethyl-4'-oxocyclohex-2'-enyl)pyran-2-one.Oxidation with selenium dioxide or t-butyl chromate then gave 6-(1'-hydroxy-2',6',6'-trimethyl-4'-oxocyclohex-2'-enyl)-4-methylpyran-2-one, which on reduction by lithium aluminium hydride and reoxidation afforded (+/-)-abscisic acid stereospecifically.