Reaction #442827

Reaction equation

glucose

2-ethyl-3-ketobutyramide

K2HPO4

MgSO4

KCl

anisaldehyde

KH2PO4

→

(2S,3S)-2 ethyl-3-hydroxybutyramide

Yield 49.2%

Solvents

ethanol

Conditions

Workup

1. 1
   workup.ADDITIONthe resulting solution was added to the culture
2. 2
   Otherthe consumption of starting material
3. 3
   Otherthe reaction was terminated
4. 4
   Otherby removing from the shaker
5. 5
   workup.ADDITIONadding 20-30 grams of Celite
6. 6
   Filtrationfiltered through a pad of Celite
7. 7
   Extractionthe clear yellow filtrate was extracted with ethyl acetate (4×200 ml)
8. 8
   Dryingdried over MgSO4
9. 9
   Filtrationfiltered
10. 10
    Otherrotary evaporated

Procedure

Geotrichum candidum (ATCC 34614) was cultured according to the method of Buisson and Azerad (Tet. Lett. 27, 2631-2634 (1986), herein incorporated by reference) in one liter of a medium of glucose (30 grams), KH2PO4 (1 gram), K2HPO4 (2 grams), corn steep liquor (10 grams) MgSO4.7H20 (0.5 gram), NaNO3 (2 grams), FeSO4.7H20 (0.02 gram), and KCl (0.5 gram) with rotary shaking at 25° C. Two grams of 2-ethyl-3-ketobutyramide was dissolved in 2 ml of 95% ethanol, the resulting solution was added to the culture, and shaking was resumed. The reaction was followed by TLC (staining with anisaldehyde) to monitor the consumption of starting material and the production of product alcohol. After 48-72 hours the reaction was judged complete, and the reaction was terminated by removing from the shaker and adding 20-30 grams of Celite. The resulting suspension was suction filtered through a pad of Celite and the clear yellow filtrate was extracted with ethyl acetate (4×200 ml). The extracts were combined, dried over MgSO4, filtered, and rotary evaporated to leave 1 gram of (2S,3S)-2 ethyl-3-hydroxybutyramide as a yellowish solid.

Source