608-41-3

Upstream product

• 100806-42-6 (E)-(2S,3S)-3-Hydroxy-2-methyl-hex-4-enoic acid 
• 113564-09-3 (E,2R^*,3S^*)-3-hydroxy-2-methyl-4-hexenoic acid 
• 642-92-2 D,L-threo-β-methylaspartic acid 
• 759-65-9 diethyl oxalpropionate 
• 93504-92-8 2-hydroxy-3-methylbutanedioic acid diethyl ester 
• 63921-06-2 3-methyl-2-oxo-butane-1,4-dioic acid dimethyl ester 

Downstream Products

• 15981-91-6 2-amino-5-methylpyrimidin-4-one 
• 65-71-4 thymin 
• 5380-37-0 (2S,3S)-2-Hydroxy-3-methyl-succinic acid 
• 5380-36-9 (-)-threo-3-Methylaepfelsaeure 
• 5380-36-9 (+)-erythro-3-Methylaepfelsaeure 
• 5380-37-0 (2S,3R)-2-Hydroxy-3-methyl-succinic acid 
• 50460-80-5 (2S,3R)-2-Hydroxy-3-methylbernsteinsaeure-dimethylester 
• 50460-80-5 dimethyl 2-hydroxy-3-methylbutane-1,4-dioate 
• 50460-80-5 dimethyl 2-hydroxy-3-methylbutane-1,4-dioate 
• 85199-56-0 2-Methyl-3-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-succinic acid dimethyl ester 
• 89497-03-0 (2R,3R)-2-Methyl-3-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-succinic acid dimethyl ester 
• 85249-22-5 (2S,3R)-2-Methyl-3-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-succinic acid dimethyl ester 

Relevant academic research and scientific papers

On the Stereochemistry of E'- and E''-Reactions

The decarboxylative E'-dehydration of β,γ-unsaturated δ-hydroxy acids with DMF-dineopentylacetal shows SYN-faciality irrespective of whether the conformation of the hydroxy group relative to the double bond axis is anticlinal or synclinal.

Synthesis of erythro-2-Hydroxy-3-methylbutane-1,4-dioic Acid

Reduction of ethyl 3-methyl-2-oxobutane-1,4-dioate (3) with sodium borohydride furnishes a 6:1 mixture of ethyl erythro-2-hydroxy-3-methylbutane-1,4-dioate (8) and ethyl threo-2-hydroxy-3-methylbutane-1,4-dioate (18).Hydrolysis of this mixture with aq. hydrochloric acid gives a mixture of acids from which pure erythro-2-hydroxy-3-methylbutane-1,4-dioic acid (4) has been isolated.The stereochemistry of 4 has been establishrd by PMR and by transforming it to the anhydride, erythro-dihydro-3-acetyloxy-4-methyl-2,5-furandione (26).

The Use of Microorganisms in Organic Synthesis. II. Microbiological Asymmetric Reduction of 2-Methyl-3-oxosuccinates

In order to synthesize four optically active methyl 2-methylmalates (10-13), microbiological asymmetric reduction of the corresponding dimethyl 2-methyl-3-oxosuccinate (9) was carried out.The β-keto diester 9 was found to be reduced by fermenting baker's yeast (Saccharomyces cerevisiae) and Candida albicans to afford a mixture of the (2R,3R)-isomer 10 and the (2S,3R)-isomer 11.Although the optical purity of 10 produced by Candida albicans was reasonably high (95percent e.e.), optical yields of other products were unexpectedly low.However, identification of the four possible isomers 14-17 was found to be easily carried out by means of nuclear magnetic resonance spectroscopy.Keywords - α-methyl-β-keto ester; methylmalate; asymmetric reduction; microbiological reduction; yeast; methyl 2-methylmalate